Novel Avian Influenza A(H5N6) Virus in Wild Birds, South Korea, 2023.

We isolated novel reassortant avian influenza A(H5N6) viruses containing genes from clade 2.3.4.4b H5N1 virus and low pathogenicity avian influenza viruses in carcasses of whooper swans and bean geese in South Korea during December 2023. Neuraminidase gene was from a clade 2.3.4.4b H5N6 virus infecting poultry and humans in China.

Comparison of Cefazolin/Metronidazole to Ampicillin/Sulbactam as Preoperative Antibiotics in Colorectal Surgery: A Retrospective, Single-Center Cohort Study.

AIM: The use of prophylactic antibiotics prior to colorectal surgery reduces surgical site infections. Cefazolin and metronidazole are used as a standard regimen. Ampicillin/sulbactam may be an alternative, but current data are limited. We compared the efficacy of ampicillin/sulbactam with cefazolin and metronidazole as prophylactic antibiotics. METHODS: Patients who underwent colorectal surgery at Inha University Hospital between 2010 and 2020 were treated prophylactically with cefazolin and metronidazole or ampicillin/sulbactam, and observed for 30 days following surgery. The primary outcome was surgical site infections. The secondary outcomes were deep/organ infections and the need for drainage. RESULTS: SSIs occurred in 2.6% (17/646) of the ampicillin/sulbactam group, whose rate was not inferior to the occurrence in the group receiving cefazolin and metronidazole (3.8%, 21/556). There was no significant difference between the two groups in the secondary outcomes. CONCLUSIONS: Compared to the cefazolin and metronidazole combination, ampicillin/sulbactam is not inferior as a preoperative prophylactic antibiotic regimen for colorectal surgery.

Adverse events of a third dose of BNT162b2 mRNA COVID-19 vaccine among Korean healthcare workers.

Due to the urgency of controlling the coronavirus disease 2019 pandemic, coronavirus disease 2019 messenger ribonucleic acid (mRNA) vaccines have been expeditiously approved and introduced in several countries without sufficient evaluation for adverse events. We analyzed adverse events among Korean healthcare workers who received all 3 doses of the BNT162b2 mRNA vaccine. This survey was conducted among hospital workers of Inha University Hospital who had received the BNT162b2 mRNA vaccine for their first, second, third rounds, and using a diary card. The surveyed adverse events included local (redness, edema, and injection site pain) and systemic (fever, fatigue, headache, chill, myalgia, arthralgia, vomiting, diarrhea, pruritis, and urticaria) side effects and were divided into 5 grades (Grade 0 = none - Grade 4 = critical). Based on adverse events reported at least once after any of the 3 doses, the most common systemic adverse reactions were chills and headache (respectively, 62.6%, 62.4%), followed by myalgia (55.3%), arthralgia (53.4%), fatigue (51.6%), pruritus (38.1%), and fever (36.5%). The frequency and duration of adverse events were significantly greater in women (P < .05) than men. Except for redness, pruritus, urticaria, and most adverse reactions had a higher rate of occurrence after the third dose in subjects who also had reactions with the second dose. However, grade 4 adverse events did occur with the third dose in some patients, even if there were no side effects with the first and second doses. Adverse events experienced with the first and second doses of the BNT162b2 mRNA vaccine in Korean healthcare workers increased the incidence of adverse events at the time of the third dose. On the other hand, grade 4 adverse events could still occur with the third dose even though there were no side effects with the first and second doses.

Tissue-engineered vascular graft based on a bioresorbable tubular knit scaffold with flexibility, durability, and suturability for implantation.

The tissue-engineered vascular graft (TEVG) is a technology used to recreate a blood vessel by using vascular cells (endothelial cells and smooth muscle cells) and their scaffolds, and is a promising approach as a clinically feasible alternative for small-diameter blood vessel replacement. Since mechanical damage occurs during/after implantation, it needs flexibility and durability to withstand the mechanical damage to be applied. To achieve this, we applied a bioresorbable polyglycolic acid (PGA) fiber-knitted tubular scaffold for vascular endothelial and smooth muscle cell layers. Similar to the native rat aorta, the knitted tubular scaffold (130 µm-thick PGA fiber) exhibited mechanical performance at 150 mN for up to 40% strain for axial stress and at 90 mN for up to 5% strain for circumferential stress. After co-culturing, a vascular barrier comprised of an inner layer of endothelial cells and an outer layer of smooth muscle cells between tubular knits was observed. Up to 93.6% of the co-cultured cells were retained even after bending 50 times, and the suturability to flow liquid without any leakage in various shapes, such as an L-shape or a Y-shape, was acceptable. Taken together, these results support that the PGA tubular knit plays multifunctional roles, such as a porous three-dimensional matrix to attach and grow the vascular cells, and as a flexible and durable scaffold for the suture. Therefore, we suggest that the bioresorbable PGA tubular knit scaffold is a promising scaffold for TEVGs.

Comparing the Impact of Upper Body Control and Core Muscle Stabilization Training on Landing Biomechanics in Individuals with Functional Ankle Instability: A Randomized Controlled Trial.

Functional ankle instability (FAI), which is characterized by recurrent ankle sprains and perceived joint instability, arises from various factors contributing to compromised biomechanical control during activities, particularly those involving landing tasks. While current research predominantly addresses lower-extremity and core stabilization interventions for FAI, the contribution of upper body control to landing biomechanics in this population remains insufficiently explored. In this study, 42 participants (19 males, 23 females) with FAI were randomly assigned to either the upper-body control training group (UBCTG) or the core muscle stabilization training group (CMSTG). The groups underwent six-week interventions, with the UBCTG receiving a dynamic core exercise program including upper body control and the CMSTG receiving static core muscle training. Pre- and post-intervention assessments encompassed electromyography of the gastrocnemius, tibialis anterior, and peroneus longus, motion analysis of the lower extremities, and ground reaction force (GRF) readings during a single-leg-jump task. Additionally, dynamic balance was assessed using the Y balance test and self-reported measurements of ankle instability were performed. The results showed similar increases in muscle activation, joint movement, and self-reported ankle instability scores within both groups. However, significant between-group differences were observed in terms of knee flexion angle, dynamic balance, and ankle instability scores, favoring the UBCTG. Although the peak vertical GRF significantly decreased and the time to peak vertical GRF increased in both groups, more changes were noted in the UBCTG. Our results demonstrated that dynamic core exercises with additional upper body control training enhance landing biomechanics, dynamic balance, and stability in individuals with FAI. Consequently, we recommend incorporating shoulder girdle exercises, proprioceptive drills, and balance exercises into dynamic core training.

Effects of Augmented Reality Game-Based Cognitive-Motor Training on Restricted and Repetitive Behaviors and Executive Function in Patients with Autism Spectrum Disorder.

Restricted and repetitive behaviors (RRBs) and executive dysfunction are widely acknowledged as core features and hallmarks in patients with autism spectrum disorder (ASD). This study aimed to investigate the effects of augmented reality (AR) using motivational games with cognitive-motor exercises on RRBs, executive function (EF), attention, and reaction time in patients with ASD. Twenty-four patients (range from 6 to 18 years) diagnosed with ASD were recruited from local social welfare centers and randomly allocated to the AR game-based cognitive-motor training group (study group) or the conventional cognitive training group (control group). Both groups completed 30 min training sessions, twice a week for four weeks. Outcome measures were conducted before and after the intervention. As a result, improvements were observed in all the subscales of the RRBs in the study group except for self-injurious and ritualistic behavior. Significant improvements were observed in EF and reaction time in the study group, which was significantly higher compared to the control group. With the present findings, we can suggest that cognitive-motor training using AR game-based content generates positive effects on improving executive function reaction time and accuracy of responses and has a limited effect on RRBs in patients with ASD. This can be proposed as a complementary intervention associated with individualized daily management.

Effects of Augmented Reality-Based Dual-Task Program on Physical Ability by Cognitive Stage with Developmental Disabilities.

People diagnosed with developmental disabilities are less likely to participate in physical activities even if they are provided opportunities. This study aimed to examine the effects of dual-task exercise-based augmented reality (AR) on muscle strength, muscle endurance, balance ability, and flexibility among people with developmental disabilities. Twenty-seven patients with developmental disabilities were included in the study. The intervention was based on an AR-based rehabilitation program and lasted for 8 weeks. The results showed a statistically significant improvement in muscle strength, muscle endurance, balance ability, and flexibility after the intervention (p < 0.05). The AR-based dual-task program increased interest and motivation in the high-cognitive-stage groups, while less interest and motivation were observed in the low-cognitive-stage groups. Our results suggest that an AR-based dual-task program can be an effective method to improve physical ability in patients with high cognitive levels.

Biomimetic cell-actuated artificial muscle with nanofibrous bundles.

Biohybrid artificial muscle produced by integrating living muscle cells and their scaffolds with free movement in vivo is promising for advanced biomedical applications, including cell-based microrobotic systems and therapeutic drug delivery systems. Herein, we provide a biohybrid artificial muscle constructed by integrating living muscle cells and their scaffolds, inspired by bundled myofilaments in skeletal muscle. First, a bundled biohybrid artificial muscle was fabricated by the integration of skeletal muscle cells and hydrophilic polyurethane (HPU)/carbon nanotube (CNT) nanofibers into a fiber shape similar to that of natural skeletal muscle. The HPU/CNT nanofibers provided a stretchable basic backbone of the 3-dimensional fiber structure, which is similar to actin-myosin scaffolds. The incorporated skeletal muscle fibers contribute to the actuation of biohybrid artificial muscle. In fact, electrical field stimulation reversibly leads to the contraction of biohybrid artificial muscle. Therefore, the current development of cell-actuated artificial muscle provides great potential for energy delivery systems as actuators for implantable medibot movement and drug delivery systems. Moreover, the innervation of the biohybrid artificial muscle with motor neurons is of great interest for human-machine interfaces.

Implantable Biosupercapacitor Inspired by the Cellular Redox System.

The carbon nanotube (CNT) yarn supercapacitor has high potential for in vivo energy storage because it can be used in aqueous environments and stitched to inner parts of the body, such as blood vessels. The biocompatibility issue for frequently used pseudocapacitive materials, such as metal oxides, is controversial in the human body. Here, we report an implantable CNT yarn supercapacitor inspired by the cellular redox system. In all living cells, nicotinamide adenine dinucleotide (NAD) is a key redox biomolecule responsible for cellular energy transduction to produce adenosine triphosphate (ATP). Based on this redox system, CNT yarn electrodes were fabricated by inserting a twist in CNT sheets with electrochemically deposited NAD and benzoquinone for redox shuttling. Consequently, the NAD/BQ/CNT yarn electrodes exhibited the maximum area capacitance (55.73 mF cm-2 ) under physiological conditions, such as phosphate-buffered saline and serum. In addition, the yarn electrodes showed a negligible loss of capacitance after 10 000 repeated charge/discharge cycles and deformation tests (bending/knotting). More importantly, NAD/BQ/CNT yarn electrodes implanted into the abdominal cavity of a rat's skin exhibited the stable in vivo electrical performance of a supercapacitor. Therefore, these findings demonstrate a redox biomolecule-applied platform for implantable energy storage devices.

Two-Ply Carbon Nanotube Fiber-Typed Enzymatic Biofuel Cell Implanted in Mice.

Implantable devices have emerged as a promising industry. It is inevitable that these devices will require a power source to operate in vivo. Thus, to power implantable medical devices, biofuel cells (BFCs) that generate electricity using glucose without an external power supply have been considered. Although implantable BFCs have been developed for application in vivo, they are limited by their bulky electrodes and low power density. In the present study, we attempted to apply to living mice an implantable enzymatic BFC (EBFC) that was previously reported to be a high-power EBFC comprising carbon nanotube yarn electrodes. To improve their mechanical properties and for convenient implantation, the electrodes were coated with Nafion and twisted into a micro-sized, two-ply, one-body system. When the two-ply EBFC system was implanted in the abdominal cavity of mice, it provided a high-power density of 0.3 mW/cm2. The two-ply EBFC system was injected through a needle using a syringe without surgery and the inflammatory response in vivo initially induced by the injection of the EBFC system was attenuated after 7 days, indicating the biocompatibility of the system in vivo.

Self-Helical Fiber for Glucose-Responsive Artificial Muscle.

A helical configuration confers a great advantage in artificial muscle due to great movement potential. However, most helical fibers are exposed to a high temperature to produce the coiled helical structure. Hence, thermoset polymer-composed hydrogels are difficult to fabricate as helical fibers due to their thermal degeneration. Here, we describe a self-helical hydrogel fiber that is produced without thermal exposure as a glucose-responsive artificial muscle. The sheath-core fiber was spontaneously transformed into the helical structure during the swelling state by balancing the forces between the untwisting force of the twisted nylon fiber core and the recovery force of the hydrogel sheath. To induce controllable actuation, we also applied a reversible interaction between phenylboronic acid and glucose to the self-helical hydrogel. Consequently, the maximum tensile stroke was 2.3%, and the performance was six times greater than that of the nonhelical fiber. The fiber also exhibited tensile stroke with load and a maximum work density of 130 kJ/m3. Furthermore, we showed a reversible tensile stroke in response to the change in glucose level. Therefore, these results indicate that the self-helical hydrogel fiber has a high potential for use in artificial muscles, glucose sensors, and drug delivery systems.

Sheath-run artificial muscles.

Although guest-filled carbon nanotube yarns provide record performance as torsional and tensile artificial muscles, they are expensive, and only part of the muscle effectively contributes to actuation. We describe a muscle type that provides higher performance, in which the guest that drives actuation is a sheath on a twisted or coiled core that can be an inexpensive yarn. This change from guest-filled to sheath-run artificial muscles increases the maximum work capacity by factors of 1.70 to 2.15 for tensile muscles driven electrothermally or by vapor absorption. A sheath-run electrochemical muscle generates 1.98 watts per gram of average contractile power-40 times that for human muscle and 9.0 times that of the highest power alternative electrochemical muscle. Theory predicts the observed performance advantages of sheath-run muscles.

Bio-Inspired Stretchable and Contractible Tough Fiber by the Hybridization of GO/MWNT/Polyurethane.

Spider silks represent stretchable and contractible fibers with high toughness. Those tough fibers with stretchability and contractibility are attractive as energy absorption materials, and they are needed for wearable applications, artificial muscles, and soft robotics. Although carbon-based materials and poly(vinyl alcohol) (PVA) composite fibers exhibit high toughness, they are still limited in low extensibility and an inability to operate in the wet-state condition. Herein, we report stretchable and contractible fiber with toughness that is inspired by the structure of spider silk. The bioinspired tough fiber provides 495 J/g of gravimetric toughness, which exceeds 165 J/g of spider silk. Besides, the tough fiber was reversibly stretched to ∼80% strain without damage. This toughness and stretchability are realized by hybridization of aligned graphene oxide/multiwalled carbon nanotubes in a polyurethane matrix as elastic amorphous regions and ß-sheet segments of spider silk. Interestingly, the bioinspired tough fiber contracted up to 60% in response to water and humidity similar to supercontraction of the spider silk. It exhibited 610 kJ/m3 of contractile energy density, which is higher than previously reported moisture driven actuators. Therefore, this stretchable and contractible tough fiber could be utilized as an artificial muscle in soft robotics and wearable devices.

Eco-friendly one-pot synthesis of Prussian blue-embedded magnetic hydrogel beads for the removal of cesium from water.

A simple one-step approach to fabricating Prussian blue-embedded magnetic hydrogel beads (PB-MHBs) was fabricated for the effective magnetic removal of radioactive cesium (137Cs) from water. Through the simple dropwise addition of a mixed aqueous solution of iron salts, commercial PB and polyvinyl alcohol (PVA) to an ammonium hydroxide (NH4OH) solution, the formation of hydrogel beads and the encapsulation of PB in beads were achieved in one pot through the gelation of PVA with in situ-formed iron oxide nanoparticles as the cross-linker. The obtained PB-MHBs, with 43.77 weight % of PB, were stable without releasing PB for up to 2 weeks and could be effectively separated from aqueous solutions by an external magnetic field, which is convenient for the large-scale treatment of Cs-contaminated water. Detailed Cs adsorption studies revealed that the adsorption isotherms and kinetics could be effectively described by the Langmuir isotherm model and the pseudo-second-order model, respectively. Most importantly, the PB-MHBs exhibited excellent selectivity for 137Cs in 137Cs-contaminated simulated groundwater (55 Bq/g) with a high removal efficiency (>99.5%), and the effective removal of 137Cs from real seawater by these PB-MHBs demonstrated the excellent potential of this material for practical application in the decontamination of 137Cs-contaminated seawater.

The effect of therapeutic abdominal drawing-in maneuver using ultrasonography on lateral abdominal muscle thickness and balance.

BACKGROUND: Lateral abdominal muscles control the lumbar region and this manages the stability of the trunk through co-contraction. Abdominal drawing-in maneuver (ADIM) is the basis method for spine stabilization to restore proper neuromuscular control. OBJECTIVE: To investigate the effect of therapeutic abdominal drawing-in maneuver on abdominal muscle thickness and balance. METHODS: Twenty healthy adults were divided into 2 groups. The experimental group performed a bridging exercise with ADIM whereas the control group performed a bridging exercise without ADIM. The exercise was conducted 3 times a week for 4 weeks. Ultrasonography was used to measure the thickness of abdominal muscles. Balance ability was evaluated using Tetrax device. The Wilcoxon signed ranks test for comparison of pre and post values and Mann Whitney U test for comparison between groups were used. RESULTS: After 4 weeks, there was a significant difference in the thickness of TrA between groups (p< 0.05) whereas no significant difference in IO and EO (p> 0.05). In stability values, the experimental group showed significant changes in stability indexes of standing with eyes open (NO) and standing on the pillow with eyes closed (PC) after the exercise period and there was a significant difference in NO between two groups. CONCLUSIONS: Performing the bridging exercise with abdominal drawing-in maneuver is a more effective way to strengthen the abdominal muscles and stabilize the body than bridging exercise only.

Stretchable Fiber Biofuel Cell by Rewrapping Multiwalled Carbon Nanotube Sheets.

The fiber-type biofuel cell is attractive as an implantable energy source because the fiber can modify various structures and the wound can be stitched like a suture. In addition, in daily life, the biofuel cell is forced by human motion, and stretchability is a critical requirement for real applications. Therefore, we introduce a new type of highly stretchable, stable, soft fiber biofuel cell with microdiameter dimensions as an energy harvester. The completed biofuel cell operated well in fluids similar to human fluids, such as 20 mM phosphate-buffered 0.14 M NaCl solution (39.5 mW/cm2) and human serum (36.6 µW/cm2). The fiber-type biofuel cell can be reversibly stretched up to 100% in tensile direction while producing sustainable electrical power. In addition, the unique rewrapping structure, which traps the enzyme between multiwalled carbon nanotube sheets, enormously enhanced the stability of the biofuel cell when the biofuel cell was repeatedly stretched (the power density retention increased from 63 to 99%) and operated in human serum (the power density retention increased from 29 to 86%). The fiber can be easily woven into various structures, such as McKibben braid yarn, and scaled up by series and parallel connections.

Effect of different speeds and ground environment of squat exercises on lower limb muscle activation and balance ability.

BACKGROUND: Squat is the most important exercise for the strengthening of the lower limb muscles. The muscle contraction speed and type affect the muscle activation, strength, and power. OBJECTIVE: This study aimed to investigate the influence of two different speeds of squat exercise on the activation and balance of the lower limb muscles. METHODS: Thirty-eight healthy adults randomly performed squat exercises at different speeds and in different ground environments, 3 times per week for 4 weeks. The participants' lower limb muscle activation and balance ability were evaluated before and after the training. RESULTS: There was a significant difference in muscle activation between the squats in terms of speed (fast, moderate, and slow squat) (p< 0.05). After the training periods, there was a significant difference in the rectus femoris (RF) and biceps femoris (BF) of the groups that performed the fast squat (p< 0.05). There was significant difference between the pre- and post-static balance test in the group that performed fast squats on an unstable surface (p< 0.05). After the training periods, the stability index with eyes open values, which is static balance, showed a significant difference among the groups after 4 weeks (p< 0.05). The groups that performed fast squat showed a significant difference between the pre- and post-dynamic Y balance test (p< 0.05). CONCLUSIONS: For optimal performance and effect of selected squat exercises, the speed and ground environment should be taken into consideration.

The effects of pelvic diagonal movements and resistance on the lumbar multifidus.

[Purpose] The purpose of this study was to compare the effects of pelvic diagonal movements, made with and without resistance, on the thickness of lumbar multifidus muscles. [Subjects and Methods] Participants in this study were healthy subjects who had no musculoskeletal disorders or lumbar-related pain. Participants were positioned on their side and instructed to lie with their hip flexor at 40 degrees. Ultrasonography was used for measurement, and the values of two calculations were averaged. [Results] The thickness of ipsilateral lumbar multifidus muscles showed a significant difference following the exercise of pelvic diagonal movements. The results of anterior elevation movements and posterior depression movements also demonstrated significant difference. There was no significant difference in lumbar multifidus muscles thickness between movements made with and without resistance. [Conclusion] These findings suggest that pelvic diagonal movements can be an effective method to promote muscular activation of the ipsilateral multifidus. Furthermore, researchers have concluded that resistance is not required during pelvic diagonal movements to selectively activate the core muscles.

Super-resolution fluorescent materials: an insight into design and bioimaging applications.

Living organisms are generally composed of complex cellular processes which persist only within their native environments. To enhance our understanding of the biological processes lying within complex milieus, various techniques have been developed. Specifically, the emergence of super-resolution microscopy has generated a renaissance in cell biology by redefining the existing dogma towards nanoscale cell dynamics, single synaptic vesicles, and other complex bioprocesses by overcoming the diffraction-imposed resolution barrier that is associated with conventional microscopy techniques. Besides the typical technical reliance on the optical framework and computational algorithm, super-resolution imaging microscopy resorts largely to fluorescent materials with special photophysical properties, including fluorescent proteins, organic fluorophores and nanomaterials. In this tutorial review article, with the emphasis on cell biology, we summarize the recent developments in fluorescent materials being utilized in various super-resolution techniques with successful integration into bio-imaging applications. Fluorescent proteins (FP) applied in super-resolution microscopy will not be covered herein as it has already been well summarized; additionally, we demonstrate the breadth of opportunities offered from a future perspective.