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Abstract Objective Neurodegeneration induced by inflammatory stress in multiple sclerosis (MS) leads to long‐term neurological disabilities that are not amenable to current immunomodulatory therapies. Methods and Results Here, we report that neuronal downregulation of Splicing factor 3b subunit 2 (SF3B2), a component of U2 small nuclear ribonucleoprotein (snRNP), preserves retinal ganglion cell (RGC) survival and axonal integrity in experimental autoimmune encephalomyelitis (EAE)‐induced mice. By employing an in vitro system recapitulating the inflammatory environment of MS lesion, we show that when SF3B2 levels are downregulated, cell viability and axon integrity are preserved in cortical neurons against inflammatory toxicity. Notably, knockdown of SF3B2 suppresses the expression of injury‐response and necroptosis genes and prevents activation of Sterile Alpha and TIR Motif Containing 1 (Sarm1), a key enzyme that mediates programmed axon degeneration. Interpretation Together, these findings suggest that the downregulation of SF3B2 is a novel potential therapeutic target to prevent secondary neurodegeneration in MS.

Objectives: Rapid and accurate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostic tests are crucial for controlling the spread of infections in emergency settings. This study evaluated the diagnostic accuracy of a point-of-care (POC) test based on loop-mediated isothermal amplification (LAMP) that produces rapid results within 30 min. Methods: We prospectively included adult patients (age >19 years) who were diagnosed with SARS-CoV-2 infection within the last 3 days and symptomatic patients who had visited the emergency room. Posterior nasopharyngeal (PNP) swabs and throat swabs collected by physicians were used to test the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and Cohen's Kappa coefficient (k) of the POC index and reference reverse transcription quantitative polymerase chain reaction (RT-qPCR) test devices. Results: Of the 352 participants, 102 (29.0%) tested positive via the RT-PCR-based reference test device; the RT-LAMP-based POC test had a sensitivity of 70.6% and specificity of 98.0%, with 93.5% PPV, 89.1% NPV, 35.5% PLR, and 3.4% NLR. Cohen's k correlation of results from the two devices was 0.74. The cycle threshold value between the positive and negative POC test results differed (17.6 vs. 24.6, p

Although previous studies have shown anti-cancer activity of betulinic acid (BA), a pentacyclic triterpenoid, against various cancer lines, the underlying molecular mechanisms are not well elucidated. In this study, we evaluated the mechanisms involved in the anti-cancer efficacy of BA in U937 human myeloid leukemia cells. BA exerted a significant cytotoxic effect on U937 cells through blocking cell cycle arrest at the G2/M phase and inducing apoptosis, and that the intracellular reactive oxygen species (ROS) levels increased after treatment with BA. The down-regulation of cyclin A and cyclin B1, and up-regulation of cyclin-dependent kinase inhibitor p21WAF1/CIP1 revealed the G2/M phase arrest mechanism of BA. In addition, BA induced the cytosolic release of cytochrome c by reducing the mitochondrial membrane potential with an increasing Bax/Bcl-2 expression ratio. BA also increased the activity of caspase-9 and -3, and subsequent degradation of the poly (ADP-ribose) polymerase. However, quenching of ROS by N-acetyl-cysteine, an ROS scavenger, markedly abolished BA-induced G2/M arrest and apoptosis, indicating that the generation of ROS plays a key role in inhibiting the proliferation of U937 cells by BA treatment. Taken together, our results provide a mechanistic rationale that BA exhibits anti-cancer properties in U937 leukemia cells through ROS-dependent induction of cell cycle arrest at G2/M phase and apoptosis.

Abstract Gold particles have been widely used in the treatment of prostate cancer due to their unique optical properties, such as their light-heat conversion in response to near-infrared radiation. Due to well-defined synthesis mechanisms and simple manufacturing methods, gold particles have been fabricated in various sizes and shapes. However, the low photothermal transduction efficiency in their present form is a major obstacle to practical and therapeutic uses of these particles. In the current work, we present a silica-coated gold nanoparticle cluster to address the therapeutic limit of single gold nanoparticles (AuNPs) and use its photothermal effect for treatment against PC-3, a typical prostate cancer. Due to its specific nanostructure, this gold nanocluster showed three times higher photothermal transduction efficiency than free single AuNPs. Moreover, while free single particles easily clump and lose optical properties, this silica-coated cluster form remained stable for a longer time in a given medium. In photothermal tests under near-infrared radiation, the excellent therapeutic efficacy of gold nanoclusters, referred to as AuNC@SiO2, was observed in a preclinical sample. Only the samples with both injected nanoclusters followed by photothermal treatment showed completely degraded tumors after 15 days. Due to the unique intrinsic biocompatibility and higher therapeutic effect of these silica-coated gold nanoclusters, they may contribute to enhancement of therapeutic efficacy against prostate cancer.

Abstract DNA damage is implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). However, relationships between DNA damage accumulation, DNA damage response (DDR), and upper and lower motor neuron vulnerability in human ALS are unclear; furthermore, it is unknown whether epigenetic silencing of DNA repair pathways contributes to ALS pathogenesis. We tested the hypotheses that DNA damage accumulates in ALS motor neurons along with diminished DDR, and that DNA repair genes undergo hypermethylation. Human postmortem CNS tissue was obtained from ALS cases (N = 34) and age-matched controls without neurologic disease (N = 15). Compared to age-matched controls, abasic sites accumulated in genomic DNA of ALS motor cortex and laser capture microdissection-acquired spinal motor neurons but not in motor neuron mitochondrial DNA. By immunohistochemistry, DNA damage accumulated significantly in upper and lower motor neurons in ALS cases as single-stranded DNA and 8-hydroxy-deoxyguanosine (OHdG) compared to age-matched controls. Significant DDR was engaged in ALS motor neurons as evidenced by accumulation of c-Abl, nuclear BRCA1, and ATM activation. DNA damage and DDR were present in motor neurons at pre-attritional stages and throughout the somatodendritic attritional stages of neurodegeneration. Motor neurons with DNA damage were also positive for activated p53 and cleaved caspase-3. Gene-specific promoter DNA methylation pyrosequencing identified the DNA repair genes Ogg1, Apex1, Pnkp and Aptx as hypomethylated in ALS. In human induced-pluripotent stem cell (iPSC)-derived motor neurons with familial ALS SOD1 mutations, DNA repair capacity was similar to isogenic control motor neurons. Our results show that vulnerable neurons in human ALS accumulate DNA damage, and contrary to our hypothesis, strongly activate and mobilize response effectors and DNA repair genes. This DDR in ALS motor neurons involves recruitment of c-Abl and BRCA1 to the nucleus in vivo, and repair of DNA double-strand breaks in human ALS motor neurons with SOD1 mutations in cell culture.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by gradual degeneration and elimination of motor neurons (MNs) in the motor cortex, brainstem, and spinal cord. Some familial forms of ALS are caused by genetic mutations in superoxide dismutase 1 (SOD1) but the mechanisms driving MN disease are unclear. Identifying the naturally occurring pathology and understanding how this mutant SOD1 can affect MNs in translationally meaningful ways in a valid and reliable human cell model remains to be established. Here, using CRISPR/Cas9 genome editing system and human induced pluripotent stem cells (iPSCs), we generated highly pure, iPSC-derived MNs with a SOD1-G93A missense mutation. With the wild-type cell line serving as an isogenic control and MNs from a patient-derived iPSC line with an SOD1-A4V mutation as a comparator, we identified pathological phenotypes relevant to ALS. The mutant MNs accumulated misfolded and aggregated forms of SOD1 in cell bodies and processes, including axons. They also developed distinctive axonal pathologies. Mutants had axonal swellings with shorter axon length and less numbers of branch points. Moreover, structural and molecular abnormalities in presynaptic and postsynaptic size and density were found in the mutants. Finally, functional studies with microelectrode array demonstrated that the individual mutant MNs exhibited decreased number of spikes and diminished network bursting, but increased burst duration. Taken together, we identified spontaneous disease phenotypes relevant to ALS in mutant SOD1 MNs from genome-edited and patient-derived iPSCs. Our findings demonstrate that SOD1 mutations in human MNs cause cell-autonomous proteinopathy, axonopathy, synaptic pathology, and aberrant neurotransmission.

This study was designed to examine the protective effects of the marine brown algae Petalonia binghamiae against oxidative stress-induced cellular damage and to elucidate the underlying mechanisms. P. binghamiae methanol extract (PBME) prevented hydrogen peroxide (H2O2)-induced growth inhibition and exhibited scavenging activity against intracellular reactive oxygen species (ROS) induced by H2O2 in mouse-derived C2C12 myoblasts. PBME also significantly attenuated H2O2-induced comet tail formation in a comet assay, histone γH2A.X phosphorylation, and annexin V-positive cells, suggesting that PBME prevented H2O2-induced cellular DNA damage and apoptotic cell death. Furthermore, PBME increased the levels of heme oxygenase-1 (HO-1), a potent antioxidant enzyme, associated with the induction of nuclear factor-erythroid 2 related factor 2 (Nrf2). However, zinc protoporphyrin IX, a HO-1 competitive inhibitor, significantly abolished the protective effects of PBME on H2O2-induced ROS generation, growth inhibition, and apoptosis. Collectively, these results demonstrate that PBME augments the antioxidant defense capacity through activation of the Nrf2/HO-1 pathway.

Here, we report a simple and effective method for capturing and displacement of gram-negative bacteria using aptamer-modified microbeads and acoustophoresis. As acoustophoresis allows for simultaneous washing and size-dependent separation in continuous flow mode, we efficiently obtained gram-negative bacteria that showed high affinity without any additional washing steps. The proposed device has a simple and efficient channel design, utilizing a long, square-shaped microchannel that shows excellent separation performance in terms of the purity, recovery, and concentration factor. Microbeads (10 µm) coated with the GN6 aptamer can specifically bind gram-negative bacteria. After incubation of bacteria culture sample with aptamer affinity bead, gram-negative bacteria-bound microbeads, and other unbound/contaminants can be separated by size with high purity and recovery. The device demonstrated excellent separation performance, with high recovery (up to 98%), high purity (up to 99%), and a high-volume rate (500 µL/min). The acoustophoretic separation performances were conducted using 5 Gram-negative bacteria and 5 Gram-positive bacteria. Thanks to GN6 aptamer’s binding affinity, aptamer affinity bead also showed binding affinity to multiple strains of gram-negative bacteria, but not to gram-positive bacteria. GN6 coated bead can capture Gram-negative bacteria but not Gram-positive bacteria. This study may present a different perspective in the field of early diagnosis in bacterial infectious diseases. In addition to detecting living bacteria or bacteria-derived biomarkers, this protocol can be extended to monitoring the contamination of water resources and may aid quick responses to bioterrorism and pathogenic bacterial infections.

Phloroglucinol (PG) is a component of phlorotannins, which are abundant in marine brown alga species. Recent studies have shown that PG is beneficial in protecting cells from oxidative stress. In this study, we evaluated the protective efficacy of PG in HaCaT human skin keratinocytes stimulated with oxidative stress (hydrogen peroxide, H2O2). The results showed that PG significantly inhibited the H2O2-induced growth inhibition in HaCaT cells, which was associated with increased expression of heme oxygenase-1 (HO-1) by the activation of nuclear factor erythroid 2-related factor-2 (Nrf2). PG remarkably reversed H2O2-induced excessive ROS production, DNA damage, and apoptosis. Additionally, H2O2-induced mitochondrial dysfunction was related to a decrease in ATP levels, and in the presence of PG, these changes were significantly impaired. Furthermore, the increases of cytosolic release of cytochrome c and ratio of Bax to Bcl-2, and the activation of caspase-9 and caspase-3 by the H2O2 were markedly abolished under the condition of PG pretreatment. However, the inhibition of HO-1 function using zinc protoporphyrin, a HO-1 inhibitor, markedly attenuated these protective effects of PG against H2O2. Overall, our results suggest that PG is able to protect HaCaT keratinocytes against oxidative stress-induced DNA damage and apoptosis through activating the Nrf2/HO-1 signaling pathway.

The Segway, which is a popular vehicle nowadays, is an uncertain nonlinear system and has an unknown time-varying control coefficient. Thus, we should consider the unknown time-varying control coefficient and model uncertainties to design the controller. Motivated by this observation, we propose a robust control for the Segway with unknown control coefficient and model uncertainties. To deal with the time-varying unknown control coefficient, we employ the Nussbaum gain technique. We introduce an auxiliary variable to solve the underactuated problem. Due to the prescribed performance control technique, the proposed controller does not require the adaptive technique, neural network, and fuzzy logic to compensate the uncertainties. Therefore, it can be simple. From the Lyapunov stability theory, we prove that all signals in the closed-loop system are bounded. Finally, we provide the simulation results to demonstrate the effectiveness of the proposed control scheme.

OBJECTIVES In an era when the average life expectancy and overall mortality rate have improved, Korea remains at risk for infectious disease outbreaks that place substantial burdens on the healthcare system. This study investigated trends in mortality and the economic burden of infectious diseases. METHODS Healthcare data from the Health Insurance Review and Assessment Service (2009-2019) and the Korean Statistics Information Service (1997-2019) were used. We selected 10 infectious disease groups (intestinal infections, tuberculosis, vaccine- preventable diseases, sepsis, viral hepatitis, HIV-related diseases, central nervous system infections, rheumatic heart diseases, respiratory tract infections, and arthropod-borne viral diseases). RESULTS The age-standardized mortality rate for infectious diseases increased from 27.2 per 100,000 population in 1997 to 37.1 per 100,000 population in 2019 and has had an upward trend since 2004. During this same period, significant increases were seen in respiratory tract infections and among elderly persons, especially those aged ≥85 years. The costs for infectious diseases increased from 4.126 billion US dollar (USD) in 2009 to 6.612 billion USD in 2019, with respiratory tract infections accounting for 3.699 billion USD (69%). The annual cost per patient for visits for medical care due to infectious diseases increased from 131 USD in 2009 to 204 USD in 2019. CONCLUSIONS Mortality among elderly persons and those with respiratory tract infections increased during the study period. The economic burden of infectious diseases has consistently increased, especially for respiratory tract infections. It is therefore essential to establish effective management policies that considers specific infectious diseases and patient groups.

Background/Aims There have been no nationwide studies to investigate the trends in incidence and 5-year survival rates of intra- and extrahepatic bile duct cancers and gall-bladder cancer. Therefore, our study aimed to describe the incidence and 5-year survival rates of biliary tract cancers by subsites in South Korea. Methods : A total of 86,134 patients with biliary tract cancers were selected from the National Health Information Database. Age-standardized incidence rates and annual percentage changes were calculated. Life-table methods and log-rank tests were used to determine the differences in survival rates. Cox-proportional hazard models were used to estimate the hazard ratio of the patients with biliary tract cancers. Results : The incidence rate of intra-hepatic bile duct cancer decreased by 1.3% annually from 8.8 per 100,000 in 2006 to 7.8 per 100,000 in 2015. Extrahepatic bile duct cancer also showed a decreasing trend by 2.2% per year from 8.7 per 100,000 in 2006 to 6.7 per 100,000 in 2015. Gallbladder cancer showed the greatest decline, with an annual percentage change of 2.8% from 6.3 per 100,000 to 5.2 per 100,000 during the same period. The 5-year survival rates were 30.0% in gallbladder cancer, 27.8% in extrahepatic bile duct cancer, and 15.9% in intra-hepatic bile duct cancer. Conclusion : s The overall incidence rates of intrahepatic and extrahepatic bile duct cancer and gallbladder cancer decreased from 2006 to 2015. Among biliary tract cancers, intrahepatic bile duct cancers exhibited the highest incidence rate and the worst survival rate.