Mechano-Responsive Polymers and Nanocomposites: Recent Advances for Self-Adaptive Structural Applications.

Polymer nanocomposites exhibiting remarkable mechanical properties are a focus of research for decades in structural applications. However, their practical application faces challenges due to poor interfacial load transfer, nanofiller dispersion, and processing limitations. These issues are critical in achieving stiff, strong, lightweight, and structurally integrated materials. Additionally, they often suffer from predetermined properties, which may not be effective under specific loading conditions. Addressing these challenges, the development of design strategies for mechano-responsive materials has advanced, enabling self-adaptive properties that respond to various mechanical stimuli. Drawing inspiration from natural systems, these approaches have been implemented in synthetic material systems, leveraging the design flexibility of nanocomposites as needed. Key focus areas include exploring mechanoradical reactions for dynamic mechano-responsiveness, as well as utilizing biomimetic mineralization and mechanical training for self-strengthening. This work also examines multistability, enabling on-demand deformation of materials and structures. Recent advancements in viscoelastic damping and nonreciprocal materials are discussed, highlighting their potential for directional energy absorption, transmission, and vibration control. Despite the need for significant improvements for real-world applications, mechano-responsive polymers and nanocomposites are expected to offer enormous opportunities not only in structural applications but also in other fields such as biomedical engineering, energy harvesting, and soft robotics.

Analysis of older adults visiting the emergency department with fever as a suspected Covid-19 vaccine-related adverse reaction: A retrospective multicenter study.

INTRODUCTION: After COVID-19 vaccination was initiated, the number of patients visiting the emergency department (ED) with vaccine-related adverse reactions increased. We investigated the clinical features of older adults (aged 65 years and older) visiting the ED with self-reported COVID-19 postvaccination fever. METHODS: We conducted a retrospective observational study at three EDs between March 2021 and September 2021. Patients who reported adverse reactions, fever (≥37.5 °C) and/or febrile sensation or rigors following COVID-19 vaccination were included. The demographic and clinical data of these patients were collected by reviewing their medical records. RESULTS: A total of 562 patients were selected, and 396 (70.5%) were female. The older adult group included 155 (27.6%) patients, and the median age was 75 (69-79 years). The older adults less frequently had a fever (≥37.5 °C) upon ED presentation (75.5% vs. 85.7%, respectively), used more emergency medical services (43.9% vs. 18.7%, respectively), and visited an ED more frequently during early hours (00:00-06:00) (31% vs. 20.1%, respectively) compared to the younger adults (p = 0.004, p < 0.001 and p = 0.036). Fewer older adults visited an ED within 2 days of fever onset (73.5% vs. 84%) (p = 0.012), and more older adults were admitted for medical conditions other than vaccine-related adverse reactions (32.9% vs. 4.2%) (p < 0.001). Older adults received more thorough testing (laboratory and imaging tests). Among the older adults, the admission rate was associated with age (p = 0.003). CONCLUSION: Older adults presenting with fever as an adverse reaction following COVID-19 vaccination less frequently had a fever upon visiting the ED, required more ED testing, and had higher admission rates for non-vaccination-related medical conditions.

Subacute Thyroiditis After Receiving the mRNA COVID-19 Vaccine (Moderna): The First Case Report and Literature Review in Korea.

Subacute thyroiditis (SAT) is a painful thyroiditis that often requires steroid therapy. Here, we report the first case of severe SAT in a patient who received the first dose of mRNA coronavirus disease 2019 (COVID-19) vaccination. A 34-year-old man without a viral prodrome felt a lump when swallowing 5 days after his first dose of mRNA-1273 (Moderna) vaccination. Ten days after vaccination, the patient visited the hospital and was advised to rest and take nonsteroidal anti-inflammatory drugs. He revisited the hospital 10 days later as symptoms aggravated with anterior neck pain, headache, fatigue, muscle weakness, and weight loss. Thyroid hormone levels and inflammatory markers were consistent with thyrotoxicosis. A thyroid ultrasound scan revealed typical SAT findings. His symptoms rapidly improved after receiving prednisone. A week later, the patient successfully completed his second dose of the vaccine. The thyroid function test results were nearly normal 1 month after the completion of the vaccination. We report this case to raise awareness of the occurrence of SAT after COVID-19 vaccination. As the risk of COVID-19 outweighs the minor risks of the vaccine, managing the side effects of the first vaccine dose is crucial to complete COVID-19 vaccination.

Xyloneside A: A New Glycosylated Incisterol Derivative from Xylaria sp. FB.

Xylaria species are prolific natural product producers. Here, we report the characterization of a new glycosylated incisterol derivative, called xyloneside A (1) and two known lignans (2 and 3) from the ascomycetous Xylaria sp. FB. The structure of xyloneside A (1) was determined by 1D and 2D NMR spectroscopy, high-resolution electrospray ionization mass spectrometry and electronic circular dichroism measurements. Xyloneside A is composed of a 1,2,3,4,5,10,19-heptanorergosterane skeleton and a ß-D-mannopyranose moiety. This is the first report of an incisterol derivative from an Ascomycete. The biological effects of the isolated metabolites on cytotoxicity, autophagy, cell-migration, and angiogenesis were evaluated.

Herqueilenone A, a unique rearranged benzoquinone-chromanone from the Hawaiian volcanic soil-associated fungal strain Penicillium herquei FT729.

The study of a Hawaiian volcanic soil-associated fungal strain Penicillium herquei FT729 led to the isolation of one unprecedented benzoquinone-chromanone, herqueilenone A (1) and two phenalenone derivatives (2 and 3). Their structures were determined through extensive analysis of NMR spectroscopic data and gauge-including atomic orbital (GIAO) NMR chemical shifts and ECD calculations. Herqueilenone A (1) contains a chroman-4-one core flanked by a tetrahydrofuran and a benzoquinone with an acetophenone moiety. Plausible pathways for the biosynthesis of 1-3 are proposed. Compounds 2 and 3 inhibited IDO1 activity with IC50 values of 14.38 and 13.69 µM, respectively. Compounds 2 and 3 also demonstrated a protective effect against acetaldehyde-induced damage in PC-12 cells.

Dysfunction of Circulating Natural Killer T Cells in Patients With Scrub Typhus.

Background: Human natural killer T (NKT) cells are known to serve as regulatory and/or effector cells in infectious diseases. However, little is known about the role of NKT cells in Orientia tsutsugamushi infection. Accordingly, the objective of this study was to examine the level and function of NKT cells in patients with scrub typhus. Methods: This study included 62 scrub typhus patients and 62 healthy controls (HCs). NKT cell level and function in peripheral blood samples were measured by flow cytometry. Results: Proliferation of NKT cells and their ability to produce interferon-γ and interleukin-4 (IL-4) were significantly lower in scrub typhus patients compared to those in HCs. However, circulating NKT cell levels were comparable between patients and HCs. Expression levels of CD69, programmed death-1 (PD-1), lymphocyte activation gene-3 (LAG-3), and T-cell immunoglobulin domain and mucin domain-containing molecule-3 (TIM-3) were significantly increased in scrub typhus patients. Elevated expression of CD69, PD-1, LAG-3, and TIM-3, impaired proliferation, and decreased IL-4 production by NKT cells were recovered in the remission phase. Conclusions: This study demonstrates that circulating NKT cells are numerically preserved but functionally impaired in scrub typhus patients. In addition, NKT cell dysfunction is recovered in the remission phase.

Comparison between ulinastatin and nafamostat for prevention of post-endoscopic retrograde cholangiopancreatography complications: a prospective, randomized trial.

OBJECTIVES: Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The aim of this prospective trial was to compare the effect of ulinastatin and nafamostat on the prophylaxis of post-ERCP complications. METHODS: A total of 159 patients who underwent ERCP were divided into ulinastatin (n = 53), nafamostat (n = 53) and control (n = 53) groups. Each patient received ulinastatin (150,000 units), nafamostat (20 mg), or placebo from 2-4 h before ERCP to 6-8 h after ERCP. The primary endpoint was the incidence of PEP, and the secondary endpoints were the incidence of post-ERCP hyperamylasemia, hyperlipasemia and abdominal pain. RESULTS: The overall incidence of PEP was 6.3% (10/159) and no significant differences were observed between ulinastatin and nafamostat groups in terms of the incidences of PEP (1.9% and 3.8%, P = 0.560), hyperamylasemia, hyperlipasemia, and abdominal pain, although these were significantly lower than those of the control group (P < 0.001). CONCLUSIONS: There was no significant difference for preventing PEP between ulinastatin and nafamostat and both drugs were efficacious for preventing post-ERCP complications.

Protective effect of hygrolansamycin C against corticosterone-induced toxicity and oxidative stress-mediated via autophagy and the MAPK signaling pathway.

BACKGROUND: Excessive stress, a major problem in modern societies, affects people of all ages worldwide. Corticosterone is one of the most abundant hormones secreted during stressful conditions and is associated with various dysfunctions in the body. In particular, we aimed to investigate the protective effects of hygrolansamycin C (HYGC) against corticosterone-induced cellular stress, a manifestation of excessive stress prevalent in contemporary societies. METHODS: We isolated HYGC from Streptomyces sp. KCB17JA11 and subjected PC12 cells to corticosterone-induced stress. The effects of HYGC were assessed by measuring autophagy and the expression of mitogen-activated protein kinase (MAPK) phosphorylation-related genes. We used established cellular and molecular techniques to analyze protein levels and pathways. RESULTS: HYGC effectively protected cells against corticosterone-induced injury. Specifically, it significantly reduced corticosterone-induced oxidative stress and inhibited the expression of autophagy-related proteins induced by corticosterone, which provided mechanistic insight into the protective effects of HYGC. At the signaling level, HYGC suppressed c-Jun N-terminal kinase and extracellular signal-regulated kinase phosphorylation and p38 activation. CONCLUSIONS: HYGC is a promising candidate to counteract corticosterone-induced apoptosis and oxidative stress. Autophagy and MAPK pathway inhibition contribute to the protective effects of HYGC. Our findings highlight the potential of HYGC as a therapeutic agent for stress-related disorders and serve as a stepping stone for further exploration and development of stress management strategies.

Kidney biopsy can help to predict renal outcomes of patients with type 2 diabetes mellitus.

Background: In patients with type 2 diabetes mellitus (T2DM), diabetic kidney disease (DKD) is diagnosed based on clinical features. A kidney biopsy is used only in selected cases. This study aimed to reconsider the role of a biopsy in predicting renal outcomes. Methods: Clinical and laboratory parameters and renal biopsy results were obtained from 237 patients with T2DM who underwent renal biopsies at Soonchunhyang University Cheonan Hospital between January 2000 and March 2020 and were analyzed. Results: Of 237 diabetic patients, 29.1% had DKD only, 61.6% had non-DKD (NDKD), and 9.3% had DKD with coexisting NDKD (DKD/NDKD). Of the patients with DKD alone, 43.5% progressed to end-stage kidney disease (ESKD), while 15.8% of NDKD patients and 36.4% of DKD/NDKD patients progressed to ESKD (p < 0.001). In the DKD-alone group, pathologic features like ≥50% global sclerosis (p < 0.001), tubular atrophy (p < 0.001), interstitial fibrosis (p < 0.001), interstitial inflammation (p < 0.001), and the presence of hyalinosis (p = 0.03) were related to worse renal outcomes. The Cox regression model showed a higher risk of progression to ESKD in the DKD/NDKD group compared to the DKD-alone group (hazard ratio [HR], 2.73; p = 0.032), ≥50% global sclerosis (HR, 3.88; p < 0.001), and the degree of mesangial expansion (moderate: HR, 2.45; p = 0.045 and severe: HR, 6.22; p < 0.001). Conclusion: In patients with T2DM, a kidney biopsy can help in identifying patients with NDKD for appropriate treatment, and it has predictive value.

Bedside index for severity in acute pancreatitis: comparison with other scoring systems in predicting severity and organ failure.

BACKGROUND: The early identification of severe acute pancreatitis is important for the management and for improving outcomes. The bedside index for severity in acute pancreatitis (BISAP) has been considered as an accurate method for risk stratification in patients with acute pancreatitis. This study aimed to evaluate the comparative usefulness of the BISAP. METHODS: We retrospectively analyzed 303 patients with acute pancreatitis diagnosed at our hospital from March 2007 to December 2010. BISAP, APACHE-II, Ranson criteria, and CT severity index (CTSI) of all patients were calculated. We stratified the number of patiants with severe pancreatitis, pancreatic necrosis, and organ failure as well as the number of deaths by BISAP score. We used the area under the receiver-operating curve (AUC) to compare BISAP with other scoring systems, C-reactive protein (CRP), hematocrit, and body mass index (BMI) with regard to prediction of severe acute pancreatitis, necrosis, organ failure, and death. RESULTS: Of the 303 patiants, 31 (10.2%) were classified as having severe acute pancreatitis. Organ failure occurred in 23 (7.6%) patients, pancreatic necrosis in 40 (13.2%), and death in 6 (2.0%). A BISAP score of 2 was a statistically significant cutoff value for the diagnosis of severe acute pancreatitis, organ failure, and mortality. AUCs for BISAP predicting severe pancreatitis and death were 0.80 and 0.86, respectively, which were similar to those for APACHE-II (0.80, 0.87) and Ranson criteria (0.74, 0.74) and greater than AUCs for CTSI (0.67, 0.42). The AUC for organ failure predicted by BISAP, APACHE-II, Ranson criteria, and CTSI was 0.93, 0.95, 0.84 and 0.57, respectively. AUCs for BISAP predicting severity, organ failure, and death were greater than those for CRP (0.69, 0.80, 0.72), hematocrit (0.45, 0.35, 0.14), and BMI (0.41, 0.47, 0.17). CONCLUSION: The BISAP predicts severity, death, and especially organ failure in acute pancreatitis as well as APACHE-II does and better than Ranson criteria, CTSI, CRP, hematocrit, and BMI.

Targeted Isolation of N-Acetylcysteine-Containing Angucycline Derivatives from Streptomyces sp. MC16 and Their Antiproliferative Effects.

Liquid chromatography-mass spectrometry (LC-MS/MS)-based molecular networking analysis was applied to Streptomyces sp. MC16. The automatic classification of the MolNetEnhancer module revealed that its major constituent was an angucycline derivative. By targeted isolation of unique clusters in the molecular network, which showed different patterns from typical angucycline compounds, two new N-acetylcysteine-attached angucycline derivatives (1 and 2) were isolated. The structures were elucidated based on intensive NMR analysis and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). All isolated compounds (1-4) were tested for their inhibitory effects on the proliferation of A431, A549, and HeLa cell lines. Antibiotics 100-1 (3) and vineomycinone B2 (4) showed moderate inhibitory effects on these three cell lines with IC50 values ranging from 18.5 to 59.0 µM, while compounds 1 and 2 with an additional N-acetylcysteine residue showed weak inhibitory effects only on the HeLa cell line with IC50 values of 54.7 and 65.2 µM, respectively.

Throughput screening of Bacillus subtilis strains that abundantly secrete surfactin in vitro identifies effective probiotic candidates.

Since the prohibition of antibiotics as animal growth promoters, demand for effective probiotic strains has steadily increased. The goal is to maintain productivity and mitigate environmental concerns in the livestock industry. There are many probiotic animal-diet supplements available, over 2,000 products in the Republic of Korea alone, with little explanation about the desirable properties of each probiotic strain. The purpose of this study was to describe the underlying logic and methods used to select two novel strains of probiotic candidates. To economically screen these candidates, the abundance of surfactin secreted was used as an in vitro marker. We used a modified oil-misting method to screen ~2,000 spore-forming bacteria for novel strains of Bacillus subtilis. Of these, 18 strains were initially selected based on the semiquantitative criterion that they secreted more surfactin than B. subtilis ATCC21322 on Luria-Berani (LB) agar plates. The whole genome sequence was determined for two of the 18 strains to verify their identity. A phylogeny of 1,162 orthologous genes, genome contents, and genome organization confirmed them as novel strains. The surfactin profiles produced by these two strains consisted of at least four isoforms similar to standard surfactin and enhanced cellulase activities up to 50%. Four fractionated individual isoforms of surfactin suppressed inflammation induced by lipopolysaccharides. The half-maximal inhibitory concentration (IC50) was about 20 µM for each isoform. Both selected strains were susceptible to seven important antibiotics. Our results implied that an abundant secretion of surfactin was a useful biomarker in vitro and could be utilized for mining probiotic candidates through high-throughput screening of environmental samples.

Rifamycin resistance, rpoB gene mutation and clinical outcomes of Staphylococcus species isolates from prosthetic joint infections in Republic of Korea.

OBJECTIVES: We conducted an in vitro investigation of the activity of rifamycins against planktonic and biofilm states of Staphylococcus aureus and Staphylococcus epidermidis isolates from patients with prosthetic joint infections (PJIs), characterised their rpoB gene mutations, and analysed the clinical outcomes of rifampicin-resistant isolates. METHODS: A total of 110 staphylococcal isolates were collected from patients with PJI. Antimicrobials tested using the broth microdilution method included rifampicin, rifabutin, rifapentine and rifaximin. We evaluated rpoB gene mutations to identify rifampicin resistance mechanisms. Clinical outcomes were assessed in rifampicin-resistant isolates. RESULTS: The 110 staphylococcal isolates included 85 S. aureus (55% methicillin-resistant) and 25 S. epidermidis (100% methicillin-resistant). Seven S. aureus isolates and two S. epidermidis isolates were resistant to rifampicin [minimum inhibitory concentration (MIC) ≥2 µg/mL] and these isolates exhibited rpoB gene mutations. Among the 78 rifampicin-susceptible S. aureus isolates and 23 S. epidermidis isolates, 76 S. aureus isolates (97.4%) and all S. epidermidis isolates (100%) were highly susceptible (MIC ≤ 0.06 µg/mL) to other rifamycins. The minimum biofilm bactericidal concentrations for ≥50% of isolates (MBBC50) to rifampicin, rifabutin, rifapentine and rifaximin were 4, 1, 2 and 4 µg/mL for S. aureus and 1, 0.125, 0.25 and 0.5 µg/mL for S. epidermidis, respectively, among rifampicin-susceptible isolates. Among nine patients bearing rifampicin-resistant isolates, only three (33%) had successful outcomes. CONCLUSION: Rifamycins other than rifampicin show promising antistaphylococcal activity, including antibiofilm activity. Rifamycin-resistant staphylococci exhibit rpoB gene mutations.

Kurarinone induced p53-independent G0/G1 cell cycle arrest by degradation of K-RAS via WDR76 in human colorectal cancer cells.

Kurarinone (KR), a naturally occurring flavonoid in Sophora flavescens Aiton and a traditional herbal medicine, reportedly has anti-cancer activity against various cancer types both in vitro and in vivo. However, the cellular mechanism of KR remains unknown. Therefore, we aimed to elucidate the mechanism of cell cycle arrest induced by KR in human colorectal cancer cells. KR not only reduced cell proliferation but also induced G0/G1 arrest of colorectal cancer cell lines. The results of western blotting analysis showed that KR reduced the protein levels of cyclin D1/D3 and CDK4/6 by downregulating signaling proteins such as K-RAS, c-MYC, and p-extracellular signal-regulated kinase. Additionally, KR arrested the cell cycle in the G0/G1 phase in a p53-independent manner, and decreased the protein level of K-RAS by proteasomal degradation dependent on WDR76, an E3 ubiquitin ligase. From these results, we propose that KR could be a potent anti-cancer agent, acting through the degradation of K-RAS dependent on WDR76, regardless of the p53 status.

New phenalenone derivatives from the Hawaiian volcanic soil-associated fungus Penicillium herquei FT729 and their inhibitory effects on indoleamine 2,3-dioxygenase 1 (IDO1).

Phenalenone derivatives sourced from fungi are polyketides that have attracted significant interest because of their diverse chemical structures and potential bioactivities. As part of our ongoing quest to discover novel natural products with biological properties from diverse natural resources, three unreported phenalenone derivatives (1-3), named ent-12-methoxyisoherqueinone (1), (-)-scleroamide (2), and (+)-scleroamide (3), together with four known phenalenone derivatives, ent-atrovenetinone (4), isoherqueinone (5), herqueinone (6), and ent-peniciherquinone (7) were isolated from the Hawaiian soil fungus Penicillium herquei FT729, collected on the Big Island, Hawaii. Compounds 2 and 3 were enantiomers, which were separated using a chiral-phase HPLC column, which provided optically pure compounds 2 and 3. The structures of the novel compounds were established by extensive spectroscopic analyses, including 1D and 2D NMR and high-resolution ESIMS. Their absolute configurations were determined using quantum chemical electronic circular dichroism (ECD) calculations. The inhibitory activity of the isolated compounds (1-7) against indoleamine 2,3-dioxygenase 1 (IDO1) was assessed. Compounds 1, 5-7 inhibited IDO1, with IC50 values of 32.59, 36.86, 19.05, and 24.18 µM, respectively. These findings demonstrated that the phenalenone derivatives 1 and 5-7, as IDO1 inhibitors, are promising anticancer immunotherapeutic agents.

Second-line Helicobacter pylori eradication: a randomized comparison of 1-week or 2-week bismuth-containing quadruple therapy.

OBJECTIVES: The increasing levels of bacterial antibiotic resistance have increased the need to evaluate the second-line treatments for Helicobacter pylori. Bismuth-based quadruple therapy is recommended as a second-line treatment, but the optimal duration of this treatment is still debatable. We prospectively analyzed the eradication rate of H. pylori according to the duration of the second-line bismuth-based quadruple therapy. METHODS: One hundred and ninety-nine patients who failed at H. pylori eradication were prospectively randomized to receive pantoprazole 40 mg twice daily, metronidazole 500 mg thrice daily, and bismuth subcitrate 300 mg and tetracycline 500 mg four times daily for 7 days (PBMT7) or for 14 days (PBMT14). The post-treatment H. pylori status was determined by the (13) C-urea breath test. The eradication rates, drug compliance, and side effects of each group were evaluated. RESULTS: The intention-to-treat (ITT) eradication rates were 81.6% (95% CI 73.9-89.3%, 80/98) in the PBMT7 arm and 85.1% (95% CI 78.2-92.0%, 86/101) in the PBMT14 arm (p=.028, noninferiority test), while the per-protocol (PP) eradication rates were 89.6% (95% CI 83.2-96.0%, 78/87) and 96.2% (95% CI 92.0-100.0% 77/80) (p=.015, noninferiority test), respectively. The compliance was 88.8% (87/98) and 79.2% (80/101) in the PBMT7 and PBMT14 groups, respectively. (p=.066) The number of patients having severe side effects was 15.3% (15/98) and 21.8% (22/101) in the PBMT7 and PBMT14 groups, respectively, which was similar between both groups. (p=.243). CONCLUSIONS: Although PBMT7 was not inferior to PBMT14 statistically, PBMT could not demonstrate enough ITT/PP eradication rate. Therefore, it could be better to extend the duration of treatment for 2 weeks for the second-line treatment of H. pylori in Korea.

Efficacy and Safety of the Cudrania tricuspidata Extract on Functional Dyspepsia: A Randomized Double-Blind Placebo-Controlled Multicenter Study.

Cudrania tricuspidata is a folk remedy used to treat inflammation in patients with tumors or liver damage. This study investigated the efficacy of Cudrania tricuspidata extract (CTE) for relieving the symptoms of functional dyspepsia. In an 8-week, randomized, double-blind, placebo-controlled study, 100 adults with any condition featured in the Rome IV criteria and a Gastrointestinal Symptoms Scale (GIS) score ≥4 were randomly allocated to take either a placebo (maltodextrin) or a 50 mg CTE tablet, which equally included celluloses, magnesium stearate, and silicon dioxide, twice daily, 20 January 2020, and 3 August 2020. Among the 83 participants finally analyzed, the CTE group was associated with a significant reduction in the gastrointestinal symptom rating scale (day 0: 8.0 ± 5.2, day 28: 4.7 ± 3.9, and day 56: 2.3 ± 2.4, p < 0.001, respectively) in comparison with the control group (day 0: 8.1 ± 4.7, day 28: 7.8 ± 5.7, and day 56: 7.5 ± 6.6, p > 0.05) after adjusting for smoking, drinking, eating habits, stress levels, and caffeine intake. The CTE group resulted in significant improvements of GIS, Nepean Dyspepsia Index (Korean version), and functional dyspepsia-related quality of life over time. There were no different adverse events (p = 0.523). These findings suggest that CTE is safe and efficacious for alleviating gastrointestinal symptoms in patients with functional dyspepsia.

Hydrogel Surface-Modified Polyurethane Copolymer Film with Water Permeation Resistance and Biocompatibility for Implantable Biomedical Devices.

To use implantable biomedical devices such as electrocardiograms and neurostimulators in the human body, it is necessary to package them with biocompatible materials that protect the internal electronic circuits from the body's internal electrolytes and moisture without causing foreign body reactions. Herein, we describe a hydrogel surface-modified polyurethane copolymer film with concurrent water permeation resistance and biocompatibility properties for application to an implantable biomedical device. To achieve this, hydrophobic polyurethane copolymers comprising hydrogenated poly(ethylene-co-butylene) (HPEB) and aliphatic poly(carbonate) (PC) were synthesized and their hydrophobicity degree and mechanical properties were adjusted by controlling the copolymer composition ratio. When 10 wt% PC was introduced, the polyurethane copolymer exhibited hydrophobicity and water permeation resistance similar to those of HPEB; however, with improved mechanical properties. Subsequently, a hydrophilic poly(vinyl pyrrolidone) (PVP) hydrogel layer was formed on the surface of the polyurethane copolymer film by Fenton reaction using an initiator and crosslinking agent and the effect of the initiator and crosslinking agent immobilization time, PVP concentration and crosslinking agent concentration on the hydrogel properties were investigated. Finally, MTT assay showed that the hydrogel surface-modified polyurethane copolymer film displays excellent biocompatibility.

Antimicrobial susceptibility of Staphylococcus species isolated from prosthetic joints with a focus on fluoroquinolone-resistance mechanisms.

We investigated susceptibility to antimicrobials of 89 staphylococcal species from PJIs and analyzed fluoroquinolone (FQ)-resistance mechanisms. Staphylococcal isolates showed high resistance to oral antimicrobials, with the exception of TMP-STX and linezolid. The main mechanism of resistance to FQ was mutations in quinolone-resistance-determining-regions. Fifteen percent of Staphylococcus aureus overexpressed efflux-pump genes.

Longer capsule endoscopy operation time increases the rate of complete examination of the small bowel.

BACKGROUND/AIMS: Wireless capsule endoscopes (CEs) have become a useful diagnostic tool for small bowel diseases, but they may fail to examine the entire small bowel. We analyzed the clinical experience of the MiRo CE in patients with suspected small bowel disease to assess whether longer operation time could increase the complete examination rate of the small bowel and diagnostic yield. METHODOLOGY: A total of 96 patients with suspected small bowel disease received CE examination at 4 tertiary hospitals in Korea. The recorded information was uploaded to a computer and analyzed by the physicians responsible for each patient. RESULTS: The average total capsule operation time was 11 hours and 39 minutes (range: 5 hours 18 minutes approximately 12 hours). In 87 (90.6%) out of 96 cases, the CE was able to explore the entire small bowel. In 32 cases (33.3%), it took more than 8 hours to reach the cecum. Capsule retention occurred in 2 cases (2.1%). The CE found meaningful small bowel lesions in 62 (64.6%) out of 96 total cases. CONCLUSIONS: A CE with a long operation time had more chance to explore the entire small bowel even in patients with suspected small bowel disease.