Electrochemical Synthesis of Hollow Nanoparticles via Anodic Transformation of Metastable Core-Shell Precursors.

Recent advances in electrosynthesis of nanomaterials expanded structural and compositional variations accessible by the electrochemical method; however, reliably synthesizable morphological variety fall shy of that available by conventional solvothermal synthesis. In this communication, electrochemical preparation of surfactant-free hollow nanoparticles is demonstrated. By anodic conversion of core-shell precursors with metastable cores, hollowed nickel nanoparticles with uniform dimensions were synthesized and characterized. Implementation of TEM grids as the working electrodes, identical location tracking of the morphological evolution of single particles to anodic stimulus has been demonstrated. The synthesized nanoparticles were employed as catalysts for the alkaline hydrogen evolution reaction and exhibited catalytic rates that compare favorably to the Pt/C benchmark. This marks the first pure electrochemical synthesis of hollow nanoparticles and shall contribute to the structural diversification of electrosynthesized nanomaterials.

Local Heating Induced Single-Crystalline Phase Control in Electrochemical Synthesis of Nanomaterials.

Development of synthetic strategies selectively yielding single crystals is desired owing to the facet-dependent chemical reactivities. Recent advances in electrochemical materials synthesis yielded nanomaterials that are surfactant-free, however, typically in polycrystalline forms. In this work, an electrochemical synthetic strategy selectively yielding single-crystalline nanoparticles by implementation of surface-selective heating of the working electrode is developed. Single crystals of copper, silver, gold, and platinum are afforded, and the crystallinity verified by electron diffraction and chemical reactivity studies. Notably, Cu (100) surface prepared by electrochemical synthesis yielded high single product selectivity when applied to electrochemical CO2 reduction catalysis.

Laboratory evolution, transcriptomics, and modeling reveal mechanisms of paraquat tolerance.

Relationships between the genome, transcriptome, and metabolome underlie all evolved phenotypes. However, it has proved difficult to elucidate these relationships because of the high number of variables measured. A recently developed data analytic method for characterizing the transcriptome can simplify interpretation by grouping genes into independently modulated sets (iModulons). Here, we demonstrate how iModulons reveal deep understanding of the effects of causal mutations and metabolic rewiring. We use adaptive laboratory evolution to generate E. coli strains that tolerate high levels of the redox cycling compound paraquat, which produces reactive oxygen species (ROS). We combine resequencing, iModulons, and metabolic models to elucidate six interacting stress-tolerance mechanisms: (1) modification of transport, (2) activation of ROS stress responses, (3) use of ROS-sensitive iron regulation, (4) motility, (5) broad transcriptional reallocation toward growth, and (6) metabolic rewiring to decrease NADH production. This work thus demonstrates the power of iModulon knowledge mapping for evolution analysis.

The discrete single-entity electrochemistry of Pickering emulsions.

Single-entity analysis is an important research topic in electrochemistry. To date, electrode collisions and subsequent electrode-particle interactions have been studied for many types of nano-objects, including metals, polymers, and micelles. Here we extend this nano-object electrochemistry analysis to Pickering emulsions for the first time. The electrochemistry of Pickering emulsions is important because the internal space of a Pickering emulsion can serve as a reactor or template; this leads to myriad possible applications, all the while maintaining mechanical stability far superior to what is exhibited by conventional emulsions. This work showed that Pickering emulsions exhibit similar hydrodynamic behavior to other nano-objects, despite the complex structure involving hard nanoparticle surfactants, and the electron-transport mechanism into the internal volume of Pickering emulsions was elucidated. The Pickering emulsion electrochemistry platform developed here can be applied to electrochemical nanomaterial synthesis, surmounting the challenges faced by conventional synthetic strategies involving normal emulsions.

Organotropic Targeting of Biomimetic Nanoparticles to Treat Lung Disease.

Active targeting strategies aimed at improving drug homing while reducing systemic toxicity are widely being pursued in the growing field of nanomedicine. While they can be effective, these approaches often require the identification of cell-specific targets and in-depth knowledge of receptor binding interactions. More recently, there has been significant interest in biomimetic nanoformulations capable of replicating the properties of naturally occurring systems. In particular, the advent of cell membrane coating nanotechnology has enabled researchers to leverage the inherent tropisms displayed by living cells, bypassing many of the challenges associated with traditional bottom-up nanoengineering. In this work, we report on a biomimetic organotropic nanodelivery system for localizing therapeutic payloads to the lungs. Metastatic breast cancer exosomes, which are lung tropic due to their unique surface marker expression profile, are used to coat nanoparticle cores loaded with the anti-inflammatory drug dexamethasone. In vivo, these nanoparticles demonstrate enhanced accumulation in lung tissue and significantly reduce proinflammatory cytokine burden in a lung inflammation model. Overall, this work highlights the potential of using biomimetic organ-level delivery strategies for the management of certain disease conditions.

Virus-Mimicking Cell Membrane-Coated Nanoparticles for Cytosolic Delivery of mRNA.

Effective endosomal escape after cellular uptake represents a major challenge in the field of nanodelivery, as the majority of drug payloads must localize to subcellular compartments other than the endosomes in order to exert activity. In nature, viruses can readily deliver their genetic material to the cytosol of host cells by triggering membrane fusion after endocytosis. For the influenza A virus, the hemagglutinin (HA) protein found on its surface fuses the viral envelope with the surrounding membrane at endosomal pH values. Biomimetic nanoparticles capable of endosomal escape were fabricated using a membrane coating derived from cells engineered to express HA on their surface. When evaluated in vitro, these virus-mimicking nanoparticles were able to deliver an mRNA payload to the cytosolic compartment of target cells, resulting in the successful expression of the encoded protein. When the mRNA-loaded nanoparticles were administered in vivo, protein expression levels were significantly increased in both local and systemic delivery scenarios. We therefore conclude that utilizing genetic engineering approaches to express viral fusion proteins on the surface of cell membrane-coated nanoparticles is a viable strategy for modulating the intracellular localization of encapsulated cargoes.

Electrochemical synthesis of core-shell nanoparticles by seed-mediated selective deposition.

Conventional solvothermal synthesis of core-shell nanoparticles results in them being covered with surfactant molecules for size control and stabilization, undermining their practicality as electrocatalysts. Here, we report an electrochemical method for the synthesis of core-shell nanoparticles directly on electrodes, free of surfactants. By implementation of selective electrodeposition on gold cores, 1st-row transition metal shells were constructed with facile and precise thickness control. This type of metal-on-metal core-shell synthesis by purely electrochemical means is the first of its kind. The applicability of the nanoparticle decorated electrodes was demonstrated by alkaline oxygen evolution catalysis, during which the Au-Ni example displayed stable catalysis with low overpotential.

Relationship between Competency to Consent to Treatment and Psychological Well-Being: Mediating Effect of Empowerment and Emotion.

This study was conducted to evaluate the competency to consent to the treatment of psychiatric outpatients and to confirm the role of empowerment and emotional variables in the relationship between competency to consent to treatment and psychological well-being. The study participants consisted of 191 psychiatric outpatients who voluntarily consented to the study among psychiatric outpatients. As a result of competency to consent to treatment evaluation, the score of the psychiatric outpatient's consent to treatment was higher than the cut-off point for both the overall and sub-factors, confirming that they were overall good. In addition, the effect of the ability of application on psychological well-being among competency to consent to treatment was verified using PROCESS Macro, and the double mediation effect using empowerment and emotional variables was verified to provide an expanded understanding of this. As a result of the analysis, empowerment completely mediated the relation between the ability of application and psychological well-being, and the relation between the ability of application and psychological well-being was sequentially mediated by empowerment and emotion-related variables. Based on these findings, the implications and limitations of this study were discussed.

Bacteria-Inspired Nanomedicine.

The natural world has provided a host of materials and inspiration for the field of nanomedicine. By taking design cues from naturally occurring systems, the nanoengineering of advanced biomimetic platforms has significantly accelerated over the past decade. In particular, the biomimicry of bacteria, with their motility, taxis, immunomodulation, and overall dynamic host interactions, has elicited substantial interest and opened up exciting avenues of research. More recently, advancements in genetic engineering have given way to more complex and elegant systems with tunable control characteristics. Furthermore, bacterial derivatives such as membrane ghosts, extracellular vesicles, spores, and toxins have proven advantageous for use in nanotherapeutic applications, as they preserve many of the features from the original bacteria while also offering distinct advantages. Overall, bacteria-inspired nanomedicines can be employed in a range of therapeutic settings, from payload delivery to immunotherapy, and have proven successful in combatting both cancer and infectious disease.

Genetically engineered cell membrane-coated nanoparticles for targeted delivery of dexamethasone to inflamed lungs.

As numerous diseases are associated with increased local inflammation, directing drugs to the inflamed sites can be a powerful therapeutic strategy. One of the common characteristics of inflamed endothelial cells is the up-regulation of vascular cell adhesion molecule-1 (VCAM-1). Here, the specific affinity between very late antigen-4 (VLA-4) and VCAM-1 is exploited to produce a biomimetic nanoparticle formulation capable of targeting inflammation. The plasma membrane from cells genetically modified to constitutively express VLA-4 is coated onto polymeric nanoparticle cores, and the resulting cell membrane-coated nanoparticles exhibit enhanced affinity to target cells that overexpress VCAM-1 in vitro. A model anti-inflammatory drug, dexamethasone, is encapsulated into the nanoformulation, enabling improved delivery of the payload to inflamed lungs and significant therapeutic efficacy in vivo. Overall, this work leverages the unique advantages of biological membrane coatings to engineer additional targeting specificities using naturally occurring target-ligand interactions.

Biomimetic nanoparticle technology for cardiovascular disease detection and treatment.

Cardiovascular disease (CVD), which encompasses a number of conditions that can affect the heart and blood vessels, presents a major challenge for modern-day healthcare. Nearly one in three people has some form of CVD, with many suffering from multiple or intertwined conditions that can ultimately lead to traumatic events such as a heart attack or stroke. While the knowledge obtained in the past century regarding the cardiovascular system has paved the way for the development of life-prolonging drugs and treatment modalities, CVD remains one of the leading causes of death in developed countries. More recently, researchers have explored the application of nanotechnology to improve upon current clinical paradigms for the management of CVD. Nanoscale delivery systems have many advantages, including the ability to target diseased sites, improve drug bioavailability, and carry various functional payloads. In this review, we cover the different ways in which nanoparticle technology can be applied towards CVD diagnostics and treatments. The development of novel biomimetic platforms with enhanced functionalities is discussed in detail.

Stoichiometry-Controlled Synthesis of Nanoparticulate Mixed-Metal Oxyhydroxide Oxygen Evolving Catalysts by Electrochemistry in Aqueous Nanodroplets.

Mixed-metal oxyhydroxides-especially those of Ni and Fe-are one of the most active classes of materials known for catalyzing the oxygen evolution reaction (OER). Here, nanoparticulate mixed metal oxyhydroxides (of Ni, Fe, and Co) were prepared on an electrode surface by electrochemical reaction of a precursor solution encapsulated in aqueous nanodroplets (AnDs), with each of the droplets containing 10 s of attoliters of fluid. Electrode reactions and synthesis can be monitored in situ by electrochemistry as single AnD stochastically lands and interacts with the working electrode. Resultant metal oxyhydroxide nanoparticles can be size and composition controlled precisely by modulating the precursor solution stored in the AnD. Nanoparticulate metal oxyhydroxides were implemented as catalysts for the OER and exhibited superior catalysis compared to their thin-film counterparts, demonstrating a hundred-thousand-fold enhancement in atom efficiency at comparable turnover rates.

Nanoparticle Delivery of Immunostimulatory Agents for Cancer Immunotherapy.

Immunostimulatory agents, including adjuvants, cytokines, and monoclonal antibodies, hold great potential for the treatment of cancer. However, their direct administration often results in suboptimal pharmacokinetics, vulnerability to biodegradation, and compromised targeting. More recently, encapsulation into biocompatible nanoparticulate carriers has become an emerging strategy for improving the delivery of these immunotherapeutic agents. Such approaches can address many of the challenges facing current treatment modalities by endowing additional protection and significantly elevating the bioavailability of the encapsulated payloads. To further improve the delivery efficiency and subsequent immune responses associated with current nanoscale approaches, biomimetic modifications and materials have been employed to create delivery platforms with enhanced functionalities. By leveraging nature-inspired design principles, these biomimetic nanodelivery vehicles have the potential to alter the current clinical landscape of cancer immunotherapy.

Cellular responses to reactive oxygen species are predicted from molecular mechanisms.

Catalysis using iron-sulfur clusters and transition metals can be traced back to the last universal common ancestor. The damage to metalloproteins caused by reactive oxygen species (ROS) can prevent cell growth and survival when unmanaged, thus eliciting an essential stress response that is universal and fundamental in biology. Here we develop a computable multiscale description of the ROS stress response in Escherichia coli, called OxidizeME. We use OxidizeME to explain four key responses to oxidative stress: 1) ROS-induced auxotrophy for branched-chain, aromatic, and sulfurous amino acids; 2) nutrient-dependent sensitivity of growth rate to ROS; 3) ROS-specific differential gene expression separate from global growth-associated differential expression; and 4) coordinated expression of iron-sulfur cluster (ISC) and sulfur assimilation (SUF) systems for iron-sulfur cluster biosynthesis. These results show that we can now develop fundamental and quantitative genotype-phenotype relationships for stress responses on a genome-wide basis.

Identification of (R)-selective ω-aminotransferases by exploring evolutionary sequence space.

Several (R)-selective ω-aminotransferases (R-ωATs) have been reported. The existence of additional R-ωATs having different sequence characteristics from previous ones is highly expected. In addition, it is generally accepted that R-ωATs are variants of aminotransferase group III. Based on these backgrounds, sequences in RefSeq database were scored using family profiles of branched-chain amino acid aminotransferase (BCAT) and d-alanine aminotransferase (DAT) to predict and identify putative R-ωATs. Sequences with two profile analysis scores were plotted on two-dimensional score space. Candidates with relatively similar scores in both BCAT and DAT profiles (i.e., profile analysis score using BCAT profile was similar to profile analysis score using DAT profile) were selected. Experimental results for selected candidates showed that putative R-ωATs from Saccharopolyspora erythraea (R-ωAT_Sery), Bacillus cellulosilyticus (R-ωAT_Bcel), and Bacillus thuringiensis (R-ωAT_Bthu) had R-ωAT activity. Additional experiments revealed that R-ωAT_Sery also possessed DAT activity while R-ωAT_Bcel and R-ωAT_Bthu had BCAT activity. Selecting putative R-ωATs from regions with similar profile analysis scores identified potential R-ωATs. Therefore, R-ωATs could be efficiently identified by using simple family profile analysis and exploring evolutionary sequence space.

Effects of using mobile device-based academic electronic medical records for clinical practicum by undergraduate nursing students: A quasi-experimental study.

INTRODUCTION: The academic electronic medical record (AEMR) system is applied with the expectation that nursing students will be able to attain competence in healthcare decision-making and nursing informatics competencies. However, there is insufficient evidence regarding the advantage of applying mobile devices to clinical practicum. OBJECTIVES: This study aimed to examine the effect of an experiment that introduced a mobile AEMR application for undergraduate nursing students in their practicum. METHODS: A quasi-experimental design was used. The subjects were 75 third-year nursing students enrolled in clinical practicum and were divided into an experimental (practicum with AEMR) and a control (conventional practicum) group. Nursing informatics competencies, critical thinking disposition, and satisfaction with clinical practicum were measured before and after the clinical practicum for each group. The usability of the AEMR application was also examined for the experimental group after the experiment. RESULTS: After the experiment, the experimental group showed a significant increase in the informatics knowledge domain of nursing informatics competencies in the post-test. The difference in critical thinking between the experimental and control groups was not statistically significant. Regarding satisfaction with the clinical practicum, the experimental group exhibited a significantly higher level of satisfaction in "preparation of a diagnostic test or laboratory test and understanding of the results" and "nursing intervention and documentation" than the control group. Students who participated in the practicum using the AEMR application considered it useful. CONCLUSIONS: The AEMR application was an effective educational method for practicing the immediate documentation of students' observations and interventions and was available at the patients' bedsides. To improve critical thinking, it is necessary to apply a variety of approaches when solving clinical problems.

Clinical and Radiologic Outcomes of Partial Lateral Patellar Facetectomy in Total Knee Arthroplasty.

Recently, some authors have performed partial lateral patellar facetectomy in total knee arthroplasty (TKA) and reported good results. However, research on partial lateral patellar facetectomy in TKA is still lacking. The aim of this study was to evaluate the clinical and radiologic results of partial lateral patellar facetectomies in patellar non-resurfacing and resurfacing TKAs. Total 251 TKAs (patellar non-resurfacing: 131; resurfacing: 120) that were followed up for at least 24 months to evaluate the clinical and radiologic results of partial lateral patellar facetectomies in patellar non-resurfacing and resurfacing TKAs were retrospectively reviewed. The radiologic evaluations involved assessments of the patellar tilt angle and the lateral patellar displacement, and the clinical evaluations involved assessments of the Knee Society knee score, Knee Society function score, Feller patellar score, and Kujala score. In patellar non-resurfacing TKA, the average postoperative patellar tilt angle and lateral patellar displacement of the group that did not undergo facetectomy were 7.0 ± 4.8 degrees and 2.4 ± 3.6 mm, respectively, and the average postoperative patellar tilt angle and lateral patellar displacement of the group that did undergo facetectomy were 4.0 ± 3.8 degrees and 0.7 ± 2.5 mm, respectively. Significant differences were observed in the postoperative patellar tilt angle and lateral patellar displacement (p < 0.001 and p = 0.004, respectively). In patellar resurfacing TKA, while the patellar tilt angle showed a significant difference between the group that underwent facetectomy (6.7 ± 3.1 degrees) and the group that did not (8.3 ± 4.4 degrees) (p = 0.023), it exhibited no difference in the lateral patellar displacement between the two groups. In both patellar non-resurfacing TKA and resurfacing TKA, the postoperative clinical results did not show any difference between no-facetectomy group and facetectomy group. Partial lateral patellar facetectomies in patellar non-resurfacing and resurfacing TKAs improved the patellar tilt angles and patellar lateral displacements but were not related to improvements in the clinical outcomes in the minimum 2-year follow-up.

Microtensile bond strength and micromorphologic analysis of surface-treated resin nanoceramics.

PURPOSE: The aim of this study was to evaluate the influence of different surface treatment methods on the microtensile bond strength of resin cement to resin nanoceramic (RNC). MATERIALS AND METHODS: RNC onlays (Lava Ultimate) (n=30) were treated using air abrasion with and without a universal adhesive, or HF etching followed by a universal adhesive with and without a silane coupling agent, or tribological silica coating with and without a universal adhesive, and divided into 6 groups. Onlays were luted with resin cement to dentin surfaces. A microtensile bond strength test was performed and evaluated by one-way ANOVA and Tukey HSD test (α=.05). A nanoscratch test, field emission scanning electron microscopy, and energy dispersive X-ray spectroscopy were used for micromorphologic analysis (α=.05). The roughness and elemental proportion were evaluated by Kruskal-Wallis test and Mann-Whitney U test. RESULTS: Tribological silica coating showed the highest roughness, followed by air abrasion and HF etching. After HF etching, the RNC surface presented a decrease in oxygen, silicon, and zirconium ratio with increasing carbon ratio. Air abrasion with universal adhesive showed the highest bond strength followed by tribological silica coating with universal adhesive. HF etching with universal adhesive showed the lowest bond strength. CONCLUSION: An improved understanding of the effect of surface treatment of RNC could enhance the durability of resin bonding when used for indirect restorations. When using RNC for restoration, effective and systemic surface roughening methods and an appropriate adhesive are required.

Nursing Students' Satisfaction with Mobile Academic Electronic Medical Records for Undergraduate Clinical Practicum.

The purpose of study was to evaluate satisfaction with and usability of mobile academic electronic medical records (AEMR) for undergraduate nursing students' clinical practicum. After an AEMR application on mobile devices was applied to the experimental group while a PC-based EMR system was used for the control group as usual in the fall semester, 2014. Two items of practicum satisfaction such as preparation of lab test and understanding of the results, and nursing intervention and documentation were significantly higher in the experiment group. The findings of usability survey showed that students in the experiment group consider the use of mobile AEMR in their job would increase their productivity.

Assessment of the Need to Integrate Academic Electronic Medical Records Into the Undergraduate Clinical Practicum: A Focus Group Interview.

As healthcare systems demand that nurses be competent in using electronic medical records for patient care, the integration of electronic medical records into nursing curricula has become necessary. The purpose of this study was to explore how students, new nurses, clinical instructors, and faculty perceive the integration of academic electronic medical records into the undergraduate clinical practicum. From January to February 2014, four focus group interviews with 18 participants were conducted based on purposive sampling. Content analysis was used on the unabridged transcripts to extract themes and develop meaningful categories. Three major themes and eight subthemes were revealed from the focus group interviews. The major themes were "electronic medical record as a learning tool for clinical practicum," "essential functions of academic electronic medical records," and "expected outcomes of academic electronic medical record." Participants expected academic electronic medical records to enhance students' nursing informatics competencies. The findings of this study can inform the process of developing academic electronic medical records for clinical practicum, which will then augment students' informatics competencies.