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Abstract Blood-brain barrier (BBB) disintegration is a key contributor to neuroinflammation; however, the biological processes governing BBB permeability under physiological conditions remain unclear. Here, we investigate the role of NLRP3 inflammasome in BBB disruption following peripheral inflammatory challenges. Repeated intraperitoneal lipopolysaccharide administration causes NLRP3-dependent BBB permeabilization and myeloid cell infiltration into the brain. Using a mouse model with cell-specific hyperactivation of NLRP3, we identify microglial NLRP3 activation as essential for peripheral inflammation-induced BBB disruption. Conversely, NLRP3 and microglial gasdermin D (GSDMD) deficiency markedly attenuates lipopolysaccharide-induced BBB breakdown. Notably, IL-1β is not required for NLRP3-GSDMD-mediated BBB disruption. Instead, microglial NLRP3-GSDMD axis upregulates CXCL chemokines and matrix metalloproteinases around BBB via producing GDF-15, promoting the recruitment of CXCR2-containing neutrophils. Inhibition of neutrophil infiltration and matrix metalloproteinase activity significantly reduces NLRP3-mediated BBB impairment. Collectively, these findings reveal the important role of NLRP3-driven chemokine production in BBB disintegration, suggesting potential therapeutic targets to mitigate neuroinflammation.

This paper proposes a possible methodology for detecting and mitigating traffic congestion. This method is carried out using a custom-designed traffic scenario model. The model is fully developed in lieu of abundant data support from actual traffic events, which is applicable to localized traffic surveillance conditions, where massive data collection from surveilling devices is infeasible or unviable. This approach includes two parts: model construction and re-routing strategy. The model construction part focuses on the development of a traffic driving scenario, which takes various criteria such as traffic volume and traffic signal into consideration. The goal of this setup is to create a realistic-possible environment, where the proposed methods can be tested. The re-routing strategy is implemented based on the model simulation result of a medium-scale drive-able road map. The idea of the adaptive vehicle re-routing strategy is inspired by the k-shortest path algorithm, adapted with the dynamic congestion re-routing strategy. It will be shown that the model is able to automatically identify congestion patterns that are happening on any road segments, and then initiates a proper re-routing strategy to alleviate such congestion in a timely manner. Although the methodology is realized and validated within a simulated model, the concept is transparent to any transportation system under study without extra complexity. In addition, the proposed modeling and simulation technique can be used for real-time implementation in intelligent transportation management systems.

Cryopreservation, storing biological material in liquid nitrogen (LN, −196 °C), offers a valuable option for the long-term conservation of non-orthodox seeds and vegetatively propagated species in the sector of agrobiodiversity and wild flora. Although the large-scale cryobanking of germplasm collections has been increasing worldwide, the wide application of cryopreservation protocols in wild flora is hampered by difficulties in vitro propagation and a lack of universal cryopreservation protocols, among others. This study established a systematic approach to developing an in vitro culture and droplet-vitrification cryopreservation procedure for shoot tips of Scrophularia kakudensis. The standard procedure includes a two-step preculture with 10% sucrose for 31 h and with 17.5% sucrose for 16 h, osmoprotection with loading solution C4-35% (17.5% glycerol + 17.5% sucrose, w/v) for 30 min, cryoprotection with A3-80% (33.3% glycerol + 13.3% dimethyl sulfoxide + 13.3% ethylene glycol + 20.1% sucrose, w/v) at 0 °C for 60 min, and cooling and rewarming using aluminum foil strips. After unloading, a three-step regrowth procedure starting with an ammonium-free medium with growth regulators was essential for developing normal plantlets from cryopreserved shoot tips. Liquid overlay on the gelled medium two weeks after inoculation resulted in vigorous growth during subcultures. Moreover, liquid overlay increased LN regeneration by up to 80%, i.e., 23% higher than no liquid overlay.

Background/Aims To investigate whether non-alcoholic fatty liver disease (NAFLD) in individuals without generalized obesity is associated with visceral fat obesity (VFO), sarcopenia, and/or myosteatosis. Methods This cross-sectional analysis included 14,400 individuals (7,470 men) who underwent abdominal computed tomography scans during routine health examinations. The total abdominal muscle area (TAMA) and skeletal muscle area (SMA) at the 3rd lumbar vertebral level were measured. The SMA was divided into the normal attenuation muscle area (NAMA) and low attenuation muscle area, and the NAMA/TAMA index was calculated. VFO was defined by visceral to subcutaneous fat ratio, sarcopenia by body mass index-adjusted SMA, and myosteatosis by the NAMA/TAMA index. NAFLD was diagnosed with ultrasonography. Results Of the 14,400 individuals, 4,748 (33.0%) had NAFLD, and the prevalence of NAFLD among non-obese individuals was 21.4%. In regression analysis, both sarcopenia (men: odds ratio [OR] 1.41, 95% confidence interval [CI] 1.19–1.67, P

Abstract Protein disulfide isomerase (PDI) is a redox-active enzyme and also serves as a nitric oxide donor causing S-nitrosylation of cysteine residues in various proteins. Although PDI knockdown reduces α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR)-mediated neuronal activity, the underlying mechanisms are largely unknown. In the present study, we found that under physiological condition PDI knockdown increased CaMKII activity (phosphorylation) in the mouse hippocampus. However, PDI siRNA inhibited protein phosphatase (PP) 2A-mediated GluA2 S880 dephosphorylation by increasing PP2A oxidation, independent of S-nitrosylation. PDI siRNA also enhanced glutamate ionotropic receptor AMPA type subunit 1 (GluA1) S831 and GluA2 S880, but not GluA1 S845 and GluA2 Y869/Y873/Y876 phosphorylations, concomitant with the enhanced protein interacting with C kinase 1 (PICK1)-mediated AMPAR internalization. Furthermore, PDI knockdown attenuated seizure activity and neuronal damage in response to kainic acid (a non-desensitizing agonist of AMPAR). Therefore, these findings suggest that PDI may regulate surface AMPAR expression through PP2A-GluA2-PICK1 signaling pathway, and that PDI may be one of the therapeutic targets for epilepsy via AMPAR internalization without altering basal neurotransmission.

Abstract Background/Aims Regression of liver fibrosis during antiviral therapy in chronic hepatitis B (CHB) patients has been demonstrated, but data on the influence of long-term treatment with tenofovir disoproxil fumarate (TDF) on liver stiffness (LS) measured by transient elastography are scarce. We aimed to investigate the changes in LS values during the 144-week TDF therapy in treatment-naïve CHB patients. Methods This prospective observational study was conducted from April 2015 to July 2020 at CHA Bundang Medical Center. Laboratory tests and LS measurements were performed at baseline and repeated at weeks 12, 24, 48, 96, and 144. A significant decline in LS was defined as ≥ 30% decrease in LS value at week 96 from baseline. Results A total of 48 treatment-naïve CHB patients initiating TDF therapy were screened, and 36 patients were included in the final analysis (median age, 46 [interquartile range, 34.5–55.8] years; 19 men [52.8%]). During TDF therapy, the median LS values decreased from 13.8 kPa at baseline to 8.7 kPa, 6.5 kPa, and 6.4 kPa at weeks 48, 96, and 144, respectively (all P

Abstract Background Pyridoxal-5′-phosphate phosphatase/chronophin (PLPP/CIN) selectively dephosphorylates serine (S) 10 site on neurofibromin 2 (NF2, also known as merlin (moesin-ezrin-radixin-like protein) or schwannomin). p21-activated kinase 1 (PAK1) is a serine/threonine protein kinase, which is involved in synaptic activity and plasticity in neurons. NF2 and PAK1 reciprocally regulate each other in a positive feedback manner. Thus, the aim of the present study is to investigate the effects of PLPP/CIN-mediated NF2 S10 dephosphorylation on PAK1-related signaling pathways under physiological and neuroinflammatory conditions, which are largely unknown. Methods After kainate (KA) injection in wild-type, PLPP/CIN −/− and PLPP/CIN Tg mice, seizure susceptibility, PAK1 S204 autophosphorylation, nuclear factor-κB (NF-κB) p65 S276 phosphorylation, cyclooxygenase-2 (COX-2) upregulation, prostaglandin E synthase 2 (PTGES2) induction and neuronal damage were measured. The effects of 1,1'-dithiodi-2-naphthtol (IPA-3, a selective inhibitor of PAK1) pretreatment on these responses to KA were also validated. Results PLPP/CIN overexpression increased PAK1 S204 autophosphorylation concomitant with the enhanced NF2 S10 dephosphorylation in hippocampal neurons under physiological condition. Following KA treatment, PLPP/CIN overexpression delayed the seizure on-set and accelerated PAK1 S204 phosphorylation, NF-κB p65 S276 phosphorylation, COX-2 upregulation and PTGES2 induction, which were ameliorated by PLPP/CIN deletion or IPA-3. Furthermore, IPA-3 pretreatment shortened the latency of seizure on-set without affecting seizure severity (intensity) and ameliorated CA3 neuronal death induced by KA. Conclusions These findings indicate that PLPP/CIN may regulate seizure susceptibility (the latency of seizure on-set) and CA3 neuronal death in response to KA through NF2-PAK1-NF-κB-COX-2-PTGES2 signaling pathway.

Cryopreservation in liquid nitrogen (LN, −196 °C) is a unique option for the long-term conservation of threatened plant species with non-orthodox or limitedly available seeds. In previous studies, a systematic approach was used to develop a droplet-vitrification (DV) cryopreservation protocol for Postemon yatabeanus shoot tips that includes preculture with 10% sucrose, osmoprotection with C4-35%, cryoprotection with A3-80% vitrification solution, and a three-step regrowth starting with the ammonium-free medium. The tricarboxylic acid (TCA) cycle is a crucial component of plant cell metabolism as it is involved in redox state regulation and energy provision. We hypothesized that organic acids (OAs) associated with the TCA and its side reactions indirectly indicate metabolism intensity and oxidative stress development in shoot tips under the cryopreservation procedure. In this study, the contents of 14 OAs were analyzed using gas chromatography–tandem mass spectrometry (GC-MS/MS) in P. yatabeanus shoot tips in a series of treatments including individual steps of the DV procedure, additional stress imposed by non-optimum protocol conditions (no preculture, no osmoprotection, various vitrification solution composition, using vials instead of aluminum foils, etc.) and regrowth on different media with or without ammonium or growth regulators. The possible relation of OA content with the total cryoprotectant (CPA) concentration and shoot tips regeneration percentage was also explored. Regeneration of cryopreserved shoot tips reduced in descending order as follows: standard protocol condition (91%) > non-optimum vitrification solution (ca. 68%) > non-optimum preculture (60–62%) > regrowth medium (40–64%) > no osmoprotection, cryopreservation in vials (28–30%). Five OAs (glycolic, malic, citric, malonic, and lactic) were the most abundant in the fresh (control) shoot tips. The dynamic pattern of OAs during the DV procedure highly correlated (r = 0.951) with the total CPA concentration employed: it gradually increased through the preculture, osmoprotection, and cryoprotection, peaked at cooling/rewarming (6.38-fold above control level), and returned to the fresh control level after 5 days of regrowth (0.89-fold). The contents of four OAs (2-hydroxybutyric, 3-hydroxypropionic, lactic, and glycolic) showed the most significant (10-209-fold) increase at the cooling/rewarming step. Lactic and glycolic acids were the major OAs at cooling/rewarming, accounting for 81% of the total OAs content. The OAs were categorized into three groups based on their dynamics during the cryopreservation protocol, and these groups were differently affected by protocol step modifications. However, there was no straightforward relationship between the dynamics of OAs and shoot tip regeneration. The results suggest that active modulation of OAs metabolism may help shoot tips to cope with osmotic stress and the chemical cytotoxicity\ of CPAs. Further intensive studies are needed to investigate the effect of cryopreservation on cell primarily metabolism and identify oxidative stress-related biomarkers in plant materials.

Background/Aims: This study was performed to evaluate the efficacy of direct-acting antivirals (DAAs) in Korean patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) and to investigate the risk factors associated with HCC recurrence. Methods: A total of 100 patients with HCV-related HCC, who were treated with DAAs between May 2015 and December 2016, were recruited from seven university hospitals in Korea. Claim data of 526 patients with HCC obtained from the Health Insurance Review and Assessment Service in South Korea were used for external validation of the results. Results: Among the 100 patients, 88% achieved a sustained virological response (SVR) 12 weeks after the end of DAA therapy (SVR12), and 37% experienced HCC recurrence after DAA therapy. Short last HCC treatment durability (

Brain doping is a novel form of doping that involves stimulating specific brain regions to enhance sports performance. However, to the best of our knowledge, there is currently no established provision or detection method for it. As brain stimulation ultimately induces alterations in neurochemical concentrations, this study aimed to develop a diagnostic strategy for brain doping. We successfully developed and validated a sensitive simultaneous analysis method for 23 neurochemicals present in urine. Simple derivatization was employed to overcome ionization efficiency, enabling the effective detection of all the target compounds within 5 min. Additionally, we developed an animal model system using rats to replicate brain-doping scenarios and establish a diagnostic strategy. Behavior tests confirmed improved sports performance in the brain stimulation group. By examining changes in the distribution patterns of the target substances in urine samples, we observed that neurochemicals could be used as potential biomarkers for brain-doping diagnosis. The developed method allows the effective simultaneous analysis of multiple neurochemicals in biological samples and is expected to have various applications, including doping control. Thus, changes in the distribution pattern of neurochemicals could serve as a basis for brain-doping diagnosis.

Abstract Neurofibromin 2 (NF2, also known as merlin) is a tumor suppressor protein encoded by the neurofibromatosis type 2 gene NF2. NF2 is also an actin-binding protein that functions in an intrinsic signaling network critical for actin dynamics. Although protein kinase A (PKA)-mediated NF2-serin (S) 10 phosphorylation stabilizes filamentous actin (F-actin), the underlying mechanisms of NF2-S10 dephosphorylation and the role of NF2 in seizures have been elusive. Here, we demonstrate that pyridoxal-5′-phosphate phosphatase/chronophin (PLPP/CIN) dephosphorylated NF2-S10 site as well as cofilin-S3 site. In addition, NF2-S10 dephosphorylation reversely regulated murine double minute-2 (Mdm2) and postsynaptic density 95 (PSD95) degradations in an activity-dependent manner, which increased seizure intensity and its progression in response to kainic acid (KA). In addition, NF2 knockdown facilitated seizure intensity and its progress through F-actin instability independent of cofilin-mediated actin dynamics. Therefore, we suggest that PLPP/CIN may be a potential therapeutic target for epileptogenesis and NF2-associated diseases.

Background/Aims: Multiple meta-analyses and observational studies have reported that alcohol is a risk factor for liver cancer. However, whether there is a safe level of alcohol consumption remains unclear. We performed a systematic review and meta-analysis of the correlation between low-level alcohol consumption and the risk of liver cancer. Methods: Nested case-control studies and cohort studies involving the general population published prior to July 2019 were searched. In total, 28 publications (31 cohorts) with 4,899 incident cases and 10,859 liver cancer-related deaths were included. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results: Compared with those with low levels of alcohol consumption, moderate and heavy drinkers (≥1 drink/day for females and ≥2 drinks/day for males) had pooled ORs of 1.418 (95% CI, 1.192 to 1.687; p

Clinical practice guidelines are important for guiding the management of specific diseases by medical practitioners, trainees, and nurses. In some cases, the guidelines are utilized as a reference for health policymakers in controlling diseases with a large public impact. With this in mind, practice guidelines for the management of chronic hepatitis B (CHB) have been developed in the United States, Europe, and Asian-Pacific regions to suggest the best-fit recommendations for each social and medical circumstance. Recently, the Korean Association for the Study of the Liver published a revised version of its clinical practice guidelines for the management of CHB. The guidelines included updated information based on newly available antiviral agents, the most recent opinion on the initiation and cessation of treatment, and updates for the management of drug resistance, partial virological response, and side effects. Additionally, CHB management in specific situations was comprehensively revised. This review compares the similarities and differences among the various practice guidelines to identify unmet needs and improve future recommendations.

The downregulation of glutathione peroxidase-1 (GPx1) plays a role in clasmatodendrosis (an autophagic astroglial death) in the hippocampus of chronic epilepsy rats. Furthermore, N-acetylcysteine (NAC, a GSH precursor) restores GPx1 expression in clasmatodendritic astrocytes and alleviates this autophagic astroglial death, independent of nuclear factor erythroid-2-related factor 2 (Nrf2) activity. However, the regulatory signal pathways of these phenomena have not been fully explored. In the present study, NAC attenuated clasmatodendrosis by alleviating GPx1 downregulation, casein kinase 2 (CK2)-mediated nuclear factor-κB (NF-κB) serine (S) 529 and AKT-mediated NF-κB S536 phosphorylations. 2-[4,5,6,7-Tetrabromo-2-(dimethylamino)-1H-benzo[d]imidazole-1-yl]acetic acid (TMCB; a selective CK2 inhibitor) relieved clasmatodendritic degeneration and GPx1 downregulation concomitant with the decreased NF-κB S529 and AKT S473 phosphorylations. In contrast, AKT inhibition by 3-chloroacetyl-indole (3CAI) ameliorated clasmatodendrosis and NF-κB S536 phosphorylation, while it did not affect GPx1 downregulation and CK2 tyrosine (Y) 255 and NF-κB S529 phosphorylations. Therefore, these findings suggest that seizure-induced oxidative stress may diminish GPx1 expression by increasing CK2-mediated NF-κB S529 phosphorylation, which would subsequently enhance AKT-mediated NF-κB S536 phosphorylation leading to autophagic astroglial degeneration.

Ptaquiloside, a naturally occurring cancer-causing substance in bracken fern, has been detected in the meat and milk of cows fed a diet containing bracken fern. A rapid and sensitive method for the quantitative analysis of ptaquiloside in bracken fern, meat, and dairy products was developed using the QuEChERS method and liquid chromatography–tandem mass spectrometry. The method was validated according to the Association of Official Analytical Chemists guidelines and met the criteria. A single matrix-matched calibration method with bracken fern has been proposed, which is a novel strategy that uses one calibration for multiple matrices. The calibration curve ranged from 0.1 to 50 µg/kg and showed good linearity (r2 > 0.99). The limits of detection and quantification were 0.03 and 0.09 µg/kg, respectively. The intraday and interday accuracies were 83.5–98.5%, and the precision was −5 µg/kg b.w./day. The significance of this study is to evaluate commercially available products in which ptaquiloside may be present, to monitor consumer safety.

Clasmatodendrosis (an autophagic astroglial degeneration) plays an important role in the regulation of spontaneous seizure duration but not seizure frequency or behavioral seizure severity in chronic epilepsy rats. Recently, it has been reported that N-acetylcysteine (NAC), a precursor to glutathione (GSH), attenuates clasmatodendritic degeneration and shortens spontaneous seizure duration in chronic epilepsy rats, although the underlying mechanisms of its anti-convulsive effects are not fully understood. To elucidate this, the present study was designed to investigate whether NAC affects astroglial glutamine synthase (GS) expression mediated by GSH peroxidase 1 (GPx1) and/or peroxiredoxin 6 (Prdx6) in the epileptic hippocampus. As compared to control animals, GS and GPx1 expressions were upregulated in reactive CA1 astrocytes of chronic epilepsy rats, while their expressions were significantly decreased in clasmatodendritic CA1 astrocytes and reactive astrocytes within the molecular layer of the dentate gyrus. Prdx6 expression was increased in reactive CA1 astrocytes as well as clasmatodendritic CA1 astrocytes. In the molecular layer of the dentate gyrus, Prdx6 expression levels were similar to those in control animals. NAC ameliorated clasmatodendrosis through the increment of GS and GPx1 expressions, while it abolished Prdx6 upregulation. 1-hexadecyl-3-(trifluoroethgl)-sn-glycerol-2 phosphomethanol (MJ33, a selective inhibitor of aiPLA2 activity of Prdx6) alleviated clasmatodendrosis by enhancing GPx1 and GS expressions in clasmatodendritic CA1 astrocytes without changing the Prdx6 level. NAC or MJ33 did not affect GS, GPx1 and Prdx6 expression in astrocytes within the molecular layer of the dentate gyrus. These findings indicate that upregulated aiPLA2 activity of Prdx6 may abolish GPx1-mediated GS preservation and lead to clasmatodendrosis in CA1 astrocytes, which would extend spontaneous seizure duration due to impaired glutamate-glutamine conversion regulated by GS. Therefore, the present data suggest that aiPLA2 activity of Prdx6 in astrocytes may be one of the upstream effectors of seizure duration in the epileptic hippocampus.

This study investigated the effect of initially set anodic potentials (−0.3, −0.2, −0.1 and +0.1 V) on voltage production and microbial community in electroactive biofilm reactors (EBRs) treating synthetic and domestic wastewater (WW). In phase 1, EBRs were acclimated with different anodic potentials for synthetic and domestic WW. EBR (SE4) poised with +0.1 V showed the highest maximum power density (420 mW/m2) for synthetic WW, while EBR (DE3) poised with −0.1 V showed the highest maximum power density (235 mW/m2) for domestic WW. In phase 2, the EBRs were operated with a fixed external resistance (100 Ω for synthetic WW and 500 Ω for domestic WW) after the applied potentials were stopped. The EBRs showed slightly different voltage productions depending on the WW type and the initial anodic potential, but both EBRs applied with +0.1 V for synthetic (SE4) and domestic (DE4) WW showed the highest voltage production. Principal component analysis results based on denaturing gel gradient electrophoresis band profiles showed that the microbial community was completely different depending on the WW type. Nevertheless, it was found that the microbial community of EBRs applied with a negative potential (−0.3, −0.2, and −0.1 V) seemed to shift to those of EBRs applied with a positive potential (+0.1 V) regardless of WW type. Therefore, positive anodic potential is an important operating factor in electroactive biofilm development and voltage generation for rapid start-up.

The treatment of inflammatory bowel disease (IBD) has been revolutionized for the last 10 years by the increasing use of immunomodulators and biologics. With immunosuppression of this kind, opportunistic infection is an important safety concern for patients with IBD. In particular, viral hepatitis is determined by the interaction between the virus and the host’s immunity, and the risk of reactivation increases if immunity is compromised by immunosuppression therapy. Parts of Asia, including Korea, still show intermediate endemicity for the hepatitis A virus and hepatitis B virus compared with the United States and Western Europe. Thus, members of IBD research group of the Korean Association for the Study of Intestinal Diseases have produced a guideline on the prevention and management of viral hepatitis in IBD.

Background/Aims Nonalcoholic fatty liver disease (NAFLD) is becoming a worldwide epidemic, and is frequently found in patients with chronic hepatitis B (CHB). We investigated the impact of histologically proven hepatic steatosis on the risk for hepatocellular carcinoma (HCC) in CHB patients without excessive alcohol intake. Methods Consecutive CHB patients who underwent liver biopsy from January 2007 to December 2015 were included. The association between hepatic steatosis (≥ 5%) and subsequent HCC risk was analyzed. Inverse probability weighting (IPW) using the propensity score was applied to adjust for differences in patient characteristics, including metabolic factors. Results Fatty liver was histologically proven in 70 patients (21.8%) among a total of 321 patients. During the median (interquartile range) follow-up of 5.3 (2.9–8.3) years, 17 of 321 patients (5.3%) developed HCC: 8 of 70 patients (11.4%) with fatty liver and 9 of 251 patients (3.6%) without fatty liver. The five-year cumulative incidences of HCC among patients without and with fatty liver were 1.9% and 8.2%, respectively (P=0.004). Coexisting fatty liver was associated with a higher risk for HCC (adjusted hazards ratio [HR], 3.005; 95% confidence interval [CI], 1.122–8.051; P=0.03). After balancing with IPW, HCC incidences were not significantly different between the groups (P=0.19), and the association between fatty liver and HCC was not significant (adjusted HR, 1.709; 95% CI, 0.404–7.228; P=0.47). Conclusions Superimposed NAFLD was associated with a higher HCC risk in CHB patients. However, the association between steatosis per se and HCC risk was not evident after adjustment for metabolic factors.

The neural precursor cell expressed by developmentally downregulated gene 4-2 (NEDD4-2) is a ubiquitin E3 ligase that has a high affinity toward binding and ubiquitinating glutamate ionotropic receptor α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) type subunit 1 (GRIA1, also referred to GluR1 or GluA1). Since dysregulation of GRIA1 surface expression is relevant to the responsiveness to AMPA receptor (AMPAR) antagonists (perampanel and GYKI 52466) in chronic epilepsy rats, it is likely that NEDD4-2 may be involved in the pathogenesis of intractable epilepsy. However, the role of NEDD4-2-mediated GRIA1 ubiquitination in refractory seizures to AMPAR antagonists is still unknown. In the present study, both AMPAR antagonists recovered the impaired GRIA1 ubiquitination by regulating protein phosphatase 2B (PP2B)-extracellular signal-regulated kinase 1/2 (ERK1/2)-serum and glucocorticoid-regulated kinase 1 (SGK1)-NEDD4-2 signaling pathway in responders (whose seizure activities are responsive to AMPAR), but not non-responders (whose seizure activities were uncontrolled by AMPAR antagonists). In addition, cyclosporin A (CsA, a PP2B inhibitor) co-treatment improved the effects of AMPAR antagonists in non-responders, independent of AKT signaling pathway. Therefore, our findings suggest that dysregulation of PP2B-ERK1/2-SGK1-NEDD4-2-mediated GRIA1 ubiquitination may be responsible for refractory seizures and that this pathway may be a potential therapeutic target for improving the treatment of intractable epilepsy in response to AMPAR antagonists.

Abstract Background Carcinoma associated fibroblasts (CAFs or myofibroblasts) are activated fibroblasts which participate in breast tumor growth, angiogenesis, invasion, metastasis and therapy resistance. As such, recent efforts have been directed toward understanding the factors responsible for activation of the phenotype. In this study, we have investigated how changes in the mechanical stiffness of a 3D hydrogel alter the behavior and myofibroblast-like properties of human mammary fibroblasts (HMFs). Results Here, we utilized microbial transglutaminase (mTG) to mechanically tune the stiffness of gelatin hydrogels and used rheology to show that increasing concentrations mTG resulted in hydrogels with greater elastic moduli (G’). Upon encapsulation of HMFs in 200 (compliant), 300 (moderate) and 1100 Pa (stiff) mTG hydrogels, it was found that the HMFs remained viable and proliferated over the 7 day culture period. Specifically, rates of proliferation were greatest for HMFs in moderate hydrogels. Regarding morphology, HMFs in compliant and moderate hydrogels exhibited a spindle-like morphology while HMFs in stiff hydrogels exhibited a rounded morphology with several large cellular protrusions. Quantification of cell morphology revealed that HMFs cultured in all mTG hydrogels overall assumed a more elongated phenotype over time in culture; however, few significant differences in morphology were observed between HMFs in each of the hydrogel conditions. To determine whether matrix stiffness upregulated expression of ECM and myofibroblast markers, western blot was performed on HMFs in compliant, moderate and stiff hydrogels. It was found that ECM and myofibroblast proteins varied in expression during both the culture period and according to matrix stiffness with no clear correlation between matrix stiffness and a myofibroblast phenotype. Finally, TGF-β levels were quantified in the conditioned media from HMFs in compliant, moderate and stiff hydrogels. TGF-β was significantly greater for HMFs encapsulated in stiff hydrogels. Conclusions Overall, these results show that while HMFs are viable and proliferate in mTG hydrogels, increasing matrix stiffness of mTG gelatin hydrogels doesn’t support a robust myofibroblast phenotype from HMFs. These results have important implications for further understanding how modulating 3D matrix stiffness affects fibroblast morphology and activation into a myofibroblast phenotype.

Status epilepticus (SE, a prolonged seizure activity) impairs brain-blood barrier (BBB) integrity, which results in secondary complications following SE. The non-integrin 67-kDa laminin receptor (67-kDa LR) plays a role in cell adherence to laminin (a major glycoprotein component in basement membrane), and participates laminin-mediated signaling pathways including p38 mitogen-activated protein kinase (p38 MAPK). Thus, we investigated the role of 67-kDa LR in SE-induced vasogenic edema formation in the rat piriform cortex (PC). SE diminished 67-kDa LR expression, but increased laminin expression, in endothelial cells accompanied by the reduced SMI-71 (a rat BBB barrier marker) expression. Astroglial 67-kDa LR expression was also reduced in the PC due to massive astroglial loss. 67-kDa LR neutralization led to serum extravasation in the PC concomitant with the reduced SMI-71 expression. 67-kDa LR neutralization also decreased expressions of dystrophin and aquaporin-4 (AQP4). In addition, it increased p38 MAPK phosphorylation and expressions of vascular endothelial growth factor (VEGF), laminin and endothelial nitric oxide synthase (eNOS), which were abrogated by SB202190, a p38 MAPK inhibitor. Therefore, our findings indicate that 67-kDa LR dysfunction may disrupt dystrophin-AQP4 complex, which would evoke vasogenic edema formation and subsequent laminin over-expression via activating p38 MAPK/VEGF axis.

α-Amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) has been reported as one of the targets for treatment of epilepsy. Although maladaptive regulation of surface expression of glutamate ionotropic receptor AMPA type subunit 1 (GRIA1) subunit is relevant to the responsiveness to AMPAR antagonists (perampanel and GYKI 52466) in LiCl-pilocarpine-induced chronic epilepsy rats, the underlying mechanisms of refractory seizures to AMPAR antagonists have yet been unclear. In the present study, we found that both AMPAR antagonists restored the up-regulations of GRIA1 surface expression and Src family-mediated glycogen synthase kinase 3β (GSK3β)-Ca2+/cAMP response element-binding protein (CREB) phosphorylations to control levels in responders (whose seizure activities were responsive to AMPAR) but not non-responders (whose seizure activities were uncontrolled by AMPAR antagonists). In addition, 3-chloroacetyl indole (3CAI, an AKT inhibitor) co-treatment attenuated spontaneous seizure activities in non-responders, accompanied by reductions in AKT/GSK3β/CREB phosphorylations and GRIA1 surface expression. Although AMPAR antagonists reduced GRIA2 tyrosine (Y) phosphorylations in responders, they did not affect GRIA2 surface expression and protein interacting with C kinase 1 (PICK1) protein level in both responders and non-responders. Therefore, our findings suggest that dysregulation of AKT/GSK3β/CREB-mediated GRIA1 surface expression may be responsible for refractory seizures in non-responders, and that this pathway may be a potential target to improve the responsiveness to AMPAR antagonists.

Portal vein thrombosis (PVT) is a form of venous thrombosis that usually presents in chronic form without any sequalae in patients with hepatocellular carcinoma (HCC) or liver cirrhosis. Accurate differential diagnosis of bland PVT from neoplastic PVT is an important step for planning treatment options, but the acute form can be challenging. Here we present a case of acute hepatic infarction caused by acute bland PVT combined with pylephlebitis, which was misdiagnosed as infiltrative hepatic malignancy with neoplastic PVT owing to the perplexing imaging results and elevated tumor markers. (Korean J Gastroenterol 2016;68:156-160)

Radiation dermatitis can develop after fluoroscopy-guided interventional procedures. Cases of fluoroscopy-induced radiation dermatitis have been reported since 1996, mostly documented in the fields of radiology, cardiology and dermatology. Since diagnosis and treatment of fluoroscopy-induced radiation dermatitis can be difficult, high grade of suspicion is required. The extent of this reaction is determined by radiation dose, duration of exposure, type of procedure, and host factors and can be aggravated by concomitant use of photosensitizers. Follow-up is important after long and complicated procedures and efforts to minimize radiation exposure time will be necessary to prevent radiation dermatitis. Herein, we report a case of a 58-year-old man with hepatocellular carcinoma presenting with subacute radiation dermatitis after prolonged fluoroscopic exposure during transarterial chemoembolization and chemoport insertion. Physicians should be aware that fluoroscopy is a potential cause of radiation dermatitis. (Korean J Gastroenterol 2016;67:112-115)

2-Cyano-3,12-dioxo-oleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me) is a triterpenoid analogue of oleanolic acid. CDDO-Me shows anti-inflammatory and neuroprotective effects. Furthermore, CDDO-Me has antioxidant properties, since it activates nuclear factor-erythroid 2-related factor 2 (Nrf2), which is a key player of redox homeostasis. In the present study, we evaluated whether CDDO-Me affects astroglial responses to status epilepticus (SE, a prolonged seizure activity) in the rat hippocampus in order to understand the underlying mechanisms of reactive astrogliosis and astroglial apoptosis. Under physiological conditions, CDDO-Me increased Nrf2 expression in the hippocampus without altering activities (phosphorylations) of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), phosphatidylinositol-3-kinase (PI3K), and AKT. CDDO-Me did not affect seizure activity in response to pilocarpine. However, CDDO-Me ameliorated reduced astroglial Nrf2 expression in the CA1 region and the molecular layer of the dentate gyrus (ML), and attenuated reactive astrogliosis and ML astroglial apoptosis following SE. In CA1 astrocytes, CDDO-Me inhibited the PI3K/AKT pathway by activating PTEN. In contrast, CDDO-ME resulted in extracellular signal-related kinases 1/2 (ERK1/2)-mediated Nrf2 upregulation in ML astrocytes. Furthermore, CDDO-Me decreased nuclear factor-κB (NFκB) phosphorylation in both CA1 and ML astrocytes. Therefore, our findings suggest that CDDO-Me may attenuate SE-induced reactive astrogliosis and astroglial apoptosis via regulation of ERK1/2-Nrf2, PTEN-PI3K-AKT, and NFκB signaling pathways.

Non-integrin 67-kDa laminin receptor (67LR) is involved in cell adherence to the basement membrane, and it regulates the interactions between laminin and other receptors. The dysfunction of 67LR leads to serum extravasation via blood-brain barrier (BBB) disruption. Polyphenol (–)-epigallocatechin-3-O-gallate (EGCG) and pigment epithelium-derived factor (PEDF) bind to 67LR and inhibit neovascularization. Therefore, in the present study, we investigated the effects of EGCG and NU335, a PEDF-derive peptide, on BBB integrity and their possible underlying mechanisms against vasogenic edema formation induced by status epilepticus (SE, a prolonged seizure activity). Following SE, both EGCG and NU335 attenuated serum extravasation and astroglial degeneration in the rat piriform cortex (PC). Both EGCG and NU335 reversely regulated phosphatidylinositol 3 kinase (PI3K)/AKT–eNOS (endothelial nitric oxide synthase) mediated BBB permeability and aquaporin 4 (AQP4) expression in endothelial cells and astrocytes through the p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathways, respectively. Furthermore, EGCG and NU335 decreased p47Phox (a nicotinamide adenine dinucleotide phosphate oxidase subunit) expression in astrocytes under physiological and post-SE conditions. Therefore, we suggest that EGCG and PEDF derivatives may activate 67LR and its downstream effectors, and they may be considerable anti-vasogenic edema agents.

Recently, we have reported that dysfunctions of 67-kDa laminin receptor (67LR) induced by status epilepticus (SE, a prolonged seizure activity) and 67LR neutralization are involved in vasogenic edema formation, accompanied by the reduced aquaporin 4 (AQP4, an astroglial specific water channel) expression in the rat piriform cortex (PC). In the present study, we found that the blockade of 67LR activated p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathways, which enhanced phosphatidylinositol 3 kinase (PI3K)/AKT phosphorylations in endothelial cells and astrocytes, respectively. 67LR-p38 MAPK-PI3K-AKT activation in endothelial cells increased vascular permeability. In contrast, 67LR-ERK1/2-PI3K-AKT signaling pathways in astrocytes regulated astroglial viability and AQP4 expression. These findings indicate that PI3K/AKT may integrate p38 MAPK and ERK1/2 signaling pathways to regulate AQP4 expression when 67LR functionality is reduced. Thus, we suggest that 67LR-p38 MAPK/ERK1/2-PI3K-AKT-AQP4 signaling cascades may mediate serum extravasation and AQP4 expression in astroglio-vascular systems, which is one of the considerable therapeutic targets for vasogenic edema in various neurological diseases.

Following status epilepticus (SE, a prolonged seizure activity), microglial activation, and monocyte infiltration result in the inflammatory responses in the brain that is involved in the epileptogenesis. Therefore, the regulation of microglia/monocyte-mediated neuroinflammation is one of the therapeutic strategies for avoidance of secondary brain injury induced by SE. 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid methyl ester (CDDO-Me; RTA 402) is an activator of nuclear factor-erythroid 2-related factor 2 (Nrf2), which regulates intracellular redox homeostasis. In addition, CDDO-Me has anti-inflammatory properties that suppress microglial proliferation and its activation, although the underlying mechanisms have not been clarified. In the present study, CDDO-Me ameliorated monocyte infiltration without vasogenic edema formation in the frontoparietal cortex (FPC) following SE, accompanied by abrogating monocyte chemotactic protein-1 (MCP-1)/tumor necrosis factor-α (TNF-α) expressions and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation. Furthermore, CDDO-Me inhibited nuclear factor-κB (NFκB)-S276 phosphorylation and microglial transformation, independent of Nrf2 expression. Similar to CDDO-Me, SN50 (an NFκB inhibitor) mitigated monocyte infiltration by reducing MCP-1 and p38 MAPK phosphorylation in the FPC following SE. Therefore, these findings suggest, for the first time, that CDDO-Me may attenuate microglia/monocyte-mediated neuroinflammation via modulating NFκB- and p38 MAPK-MCP-1 signaling pathways following SE.

Glutathione (GSH) is an endogenous tripeptide antioxidant that consists of glutamate-cysteine-glycine. GSH content is limited by the availability of glutamate and cysteine. Furthermore, glutamine is involved in the regulation of GSH synthesis via the glutamate–glutamine cycle. P2X7 receptor (P2X7R) is one of the cation-permeable ATP ligand-gated ion channels, which is involved in neuronal excitability, neuroinflammation and astroglial functions. In addition, P2X7R activation decreases glutamate uptake and glutamine synthase (GS) expression/activity. In the present study, we found that P2X7R deletion decreased the basal GSH level without altering GSH synthetic enzyme expressions in the mouse hippocampus. P2X7R deletion also increased expressions of GS and ASCT2 (a glutamine:cysteine exchanger), but diminished the efficacy of N-acetylcysteine (NAC, a GSH precursor) in the GSH level. SIN-1 (500 μM, a generator nitric oxide, superoxide and peroxynitrite), which facilitates the cystine–cysteine shuttle mediated by xCT (a glutamate/cystein:cystine/NAC antiporter), did not affect basal GSH concentration in WT and P2X7R knockout (KO) mice. However, SIN-1 effectively reduced the efficacy of NAC in GSH synthesis in WT mice, but not in P2X7R KO mice. Therefore, our findings indicate that P2X7R may be involved in the maintenance of basal GSH levels by regulating the glutamate–glutamine cycle and neutral amino acid transports under physiological conditions, which may be the defense mechanism against oxidative stress during P2X7R activation.

Transient receptor potential canonical channel-6 (TRPC6) is one of the Ca2+-permeable non-selective cation channels. TRPC6 is mainly expressed in dentate granule cell (DGC), which is one of the most resistant neuronal populations to various harmful stresses. Although TRPC6 knockdown evokes the massive DGC degeneration induced by status epilepticus (a prolonged seizure activity, SE), the molecular mechanisms underlying the role of TRPC6 in DGC viability in response to SE are still unclear. In the present study, hyperforin (a TRPC6 activator) facilitated mitochondrial fission in DGC concomitant with increases in Lon protease-1 (LONP1, a mitochondrial protease) expression and extracellular-signal-regulated kinase 1/2 (ERK1/2) phosphorylation under physiological conditions, which were abrogated by U0126 (an ERK1/2 inhibitor) co-treatment. TRPC6 knockdown showed the opposite effects on LONP1 expression, ERK1/2 activity, and mitochondrial dynamics. In addition, TRPC6 siRNA and U0126 evoked the massive DGC degeneration accompanied by mitochondrial elongation following SE, independent of seizure severity. However, LONP1 siRNA exacerbated SE-induced DGC death without affecting mitochondrial length. These findings indicate that TRPC6-ERK1/2 activation may increase DGC invulnerability to SE by regulating LONP1 expression as well as mitochondrial dynamics. Therefore, TRPC6-ERK1/2-LONP1 signaling pathway will be an interesting and important therapeutic target for neuroprotection from various neurological diseases.

2-Cyano-3,12-dioxo-oleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me) is a triterpenoid analogue of oleanolic acid that exhibits promising anti-cancer, anti-inflammatory, antioxidant and neuroprotective activities. In addition, CDDO-Me affects cellular differentiation and cell cycle arrest, and irreversibly inhibits Lon protease-1 (LONP1). In the present study, we evaluate the effects of CDDO-Me on mitochondrial dynamics and its downstream effectors in order to understand the underlying mechanism of the neuronal death following status epilepticus (SE, a prolonged seizure activity). CDDO-Me increased dynamin-related proteins 1 (DRP1)-serine 616 phosphorylation via activating extracellular-signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK), but not protein kinase A (PKA) or protein phosphatases (PPs). In addition, CDDO-Me facilitated DRP1-mediated mitochondrial fissions, which selectively attenuated SE-induced CA1 neuronal death. Unlike CDDO-Me, LONP1 knockdown led to SE-induced massive degeneration of dentate granule cells, CA1 neurons and hilus interneurons without altering the expression and phosphorylation of DRP1, ERK1/2, JNK and PP2B. LONP1 knockdown could not inhibit SE-induced mitochondrial elongation in CA1 neurons. Co-treatment of CDDO-Me with LONP1 siRNA ameliorated only CA1 neuronal death, concomitant with abrogation of mitochondrial elongation induced by SE. Thus, our findings suggest that CDDO-Me may selectively attenuate SE-induced CA1 neuronal death by rescuing the abnormal mitochondrial machinery, independent of LONP1 activity.

Under physiological conditions, microglia are unique immune cells resident in the brain that is isolated from the systemic immune system by brain-blood barrier. Following status epilepticus (SE, a prolonged seizure activity), microglia are rapidly activated and blood-derived monocytes that infiltrate the brain; therefore, the regulations of microglia activation and monocyte infiltration are one of the primary therapeutic strategies for inhibition of undesirable consequences from SE. Roscovitine, a potent (but not selective) cyclin-dependent kinase 5 (CDK5) inhibitor, has been found to exert anti-inflammatory and microglia-inhibiting actions in several in vivo models, although the underlying mechanisms have not been clarified. In the present study, roscovitine attenuated SE-induces monocyte infiltration without vasogenic edema formation in the frontoparietal cortex (FPC), accompanied by reducing expressions of monocyte chemotactic protein-1 (MCP-1) and lysosome-associated membrane protein 1 (LAMP1) in resident microglia, while it did not affect microglia transformation to amoeboid form. Furthermore, roscovitine ameliorated the up-regulation of p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation, but not nuclear factor-κB-S276 phosphorylation. Similar to roscovitine, SB202190, a p38 MAPK inhibitor, mitigated monocyte infiltration and microglial expressions of MCP-1 and LAMP1 in the FPC following SE. Therefore, these findings suggest for the first time that roscovitine may inhibit SE-induced neuroinflammation via regulating p38 MAPK-mediated microglial responses.

Telbivudine is an L-nucleoside analogue with potent antiviral activity against hepatitis B virus (HBV). Clinical trials have shown that telbivudine has a more potent and sustained antiviral activity with a lower frequency of viral resistance than lamivudine. Although there are several reports concerning the safety profile of telbivudine, most adverse events are described as mild and transient in nature. Here we report two cases of telbivudine-induced myopathy in patients with chronic hepatitis B who were siblings.

BACKGROUND/AIMS:The accuracy of noninvasive markers to discriminate nonalcoholic steatohepatitis (NASH) is unsatisfactory. We investigated whether transient elastography (TE) could discriminate patients with NASH from those with nonalcoholic fatty liver disease (NAFLD). METHODS:The patients suspected of NAFLD who underwent liver biopsy and concomitant TE were recruited from five tertiary centers between November 2011 and December 2013. RESULTS:The study population (n = 183) exhibited a mean age of 40.6 years and male predominance (n = 111, 60.7%). Of the study participants, 89 (48.6%) had non-NASH and 94 (51.4%) had NASH. The controlled attenuation parameter (CAP) and liver stiffness (LS) were significantly correlated with the degrees of steatosis (r = 0.656, P250 dB/m; P = 0.013, OR 3.399, 95% CI 1.295-8.291 for LS>7.0 kPa; and P60 IU/L], we developed a novel CLA model for discriminating patients with NASH. The CLA model showed good discriminatory capability, with an area under the receiver operating characteristic curve (AUROC) of 0.812 (95% CI 0.724-0.880). To assess discriminatory power, the AUROCs, as determined by the bootstrap method, remained largely unchanged between iterations, with an average value of 0.833 (95% CI 0.740-0.893). CONCLUSION:This novel TE-based CLA model showed acceptable accuracy in discriminating NASH from simple steatosis. However, further studies are required for external validation.

Single-nucleotide polymorphisms (SNPs) in microRNA machinery genes might affect microRNA processing and subsequently impact tumorigenesis. The aim of this study was to investigate the associations between SNPs in microRNA machinery genes and hepatocellular carcinoma (HCC) in a Korean population. Genotyping of six SNPs in microRNA machinery genes was performed using blood samples from 147 patients with HCC and 209 healthy control subjects. None of the six SNPs in microRNA machinery genes were significantly associated with HCC development. However, among the models for six polymorphic loci-DICER (rs3742330 and rs13078), DROSHA (rs10719 and rs6877842), RAN (rs14035) and XPO5 (rs11077)-one allele combination (A-A-T-C-C-C) showed synergistic effects in terms of an increased risk of HCC development (odds ratio = 8.881, 95% confidence interval [CI] = 1.889-41.750; P = 0.002). Multivariate Cox proportional hazard regression analysis showed a significant survival benefit for the DICER rs3742330 GG compared with the AA type (hazard ratio [HR], 0.314; 95% CI, 0.135-0.730; P = 0.007) and for the RAN rs14035 CT compared with the CC genotype (HR, 0.587; 95% CI, 0.349-0.987; P = 0.044). Although we found no direct association between DICER (rs3742330 and rs13078), DROSHA (rs10719 and rs6877842), RAN (rs14035) or XPO5 (rs11077) polymorphisms and HCC risk, we demonstrated that DICER (rs3742330) and RAN (rs14035) were associated with the survival of HCC patients. Future studies with larger samples are needed to determine associations of SNPs in microRNA machinery genes with HCC risk and prognosis.