Differential diagnosis of cemento-osseous dysplasia and periapical cyst using texture analysis of CBCT.

BACKGROUND: Radiolucencies found at the root apex in patients with cemento-osseous dysplasia (COD) may be mistaken for periapical cysts (PC) of endodontic origin. The purpose of this study was to examine the utility of quantitative texture analysis using cone-beam computed tomography (CBCT) to differentiate between COD and PC. METHODS: Patients who underwent CBCT at Wonkwang University Daejeon Dental Hospital between January 2019 and December 2022 and were diagnosed with COD and PC by clinical, radiologic, and, if necessary, histopathologic examination were included. Twenty-five patients each were retrospectively enrolled in the COD and PC group. All lesions observed on axial CBCT images were manually segmented using the open-access software MaZda version 4.6 to establish the regions of interest, which were then subjected to texture analysis. Among the 279 texture features obtained, 10 texture features with the highest Fisher coefficients were selected. Statistical analysis was performed using the Mann-Whitney U-test, Welch's t-test, or Student's t-test. Texture features that showed significant differences were subjected to receiver operating characteristics (ROC) curve analysis to evaluate the differential diagnostic ability of COD and PC. RESULTS: The COD group consisted of 22 men and 3 women, while the PC group consisted of 14 men and 11 women, showing a significant difference between the two groups in terms of sex (p=0.003). The 10 selected texture features belonged to the gray level co-occurrence matrix and included the sum of average, sum of entropy, entropy, and difference of entropy. All 10 selected texture features showed statistically significant differences (p<0.05) when comparing patients with COD (n=25) versus those with PC (n=25), osteolytic-stage COD (n=11) versus PC (n=25), and osteolytic-stage COD (n=11) versus cementoblastic-stage COD (n=14). ROC curve analysis to determine the ability to differentiate between COD and PC showed a high area under the curve ranging from 0.96 to 0.98. CONCLUSION: Texture analysis of CBCT images has shown good diagnostic value in the differential diagnosis of COD and PC, which can help prevent unnecessary endodontic treatment, invasive biopsy, or surgical intervention associated with increased risk of infection.

Reduction of Squalene Epoxidase by Cholesterol Accumulation Accelerates Colorectal Cancer Progression and Metastasis.

BACKGROUND & AIMS: Squalene epoxidase (SQLE), a rate-limiting enzyme in cholesterol biosynthesis, is suggested as a proto-oncogene. Paradoxically, SQLE is degraded by excess cholesterol, and low SQLE is associated with aggressive colorectal cancer (CRC). Therefore, we studied the functional consequences of SQLE reduction in CRC progression. METHODS: Gene and protein expression data and clinical features of CRCs were obtained from public databases and 293 human tissues, analyzed by immunohistochemistry. In vitro studies showed underlying mechanisms of CRC progression mediated by SQLE reduction. Mice were fed a 2% high-cholesterol or a control diet before and after cecum implantation of SQLE genetic knockdown/control CRC cells. Metastatic dissemination and circulating cancer stem cells were demonstrated by in vivo tracking and flow cytometry analysis, respectively. RESULTS: In vitro studies showed that SQLE reduction helped cancer cells overcome constraints by inducing the epithelial-mesenchymal transition required to generate cancer stem cells. Surprisingly, SQLE interacted with GSK3ß and p53. Active GSK3ß contributes to the stability of SQLE, thereby increasing cell cholesterol content, whereas SQLE depletion disrupted the GSK3ß/p53 complex, resulting in a metastatic phenotype. This was confirmed in a spontaneous CRC metastasis mice model, where SQLE reduction, by a high-cholesterol regimen or genetic knockdown, strikingly promoted CRC aggressiveness through the production of migratory cancer stem cells. CONCLUSIONS: We showed that SQLE reduction caused by cholesterol accumulation aggravates CRC progression via the activation of the ß-catenin oncogenic pathway and deactivation of the p53 tumor suppressor pathway. Our findings provide new insights into the link between cholesterol and CRC, identifying SQLE as a key regulator in CRC aggressiveness and a prognostic biomarker.

The emerging genetic diversity of hereditary spastic paraplegia in Korean patients.

Hereditary Spastic Paraplegias (HSP) are a group of rare inherited neurological disorders characterized by progressive loss of corticospinal motor-tract function. Numerous patients with HSP remain undiagnosed despite screening for known genetic causes of HSP. Therefore, identification of novel genetic variations related to HSP is needed. In this study, we identified 88 genetic variants in 54 genes from whole-exome data of 82 clinically well-defined Korean HSP families. Fifty-six percent were known HSP genes, and 44% were composed of putative candidate HSP genes involved in the HSPome and originally reported neuron-related genes, not previously diagnosed in HSP patients. Their inheritance modes were 39, de novo; 33, autosomal dominant; and 10, autosomal recessive. Notably, ALDH18A1 showed the second highest frequency. Fourteen known HSP genes were firstly reported in Koreans, with some of their variants being predictive of HSP-causing protein malfunction. SPAST and REEP1 mutants with unknown function induced neurite abnormality. Further, 54 HSP-related genes were closely linked to the HSP progression-related network. Additionally, the genetic spectrum and variation of known HSP genes differed across ethnic groups. These results expand the genetic spectrum for HSP and may contribute to the accurate diagnosis and treatment for rare HSP.

Comparison of the canal transportation of ProTaper GOLD, WaveOne GOLD, and TruNatomy in simulated double-curved canals.

BACKGROUND: In root canal preparations, it is important to maintain the original canal shape. However, it is difficult to accomplish this, especially due to the complex canal anatomy. This study aimed to compare the shaping ability of the ProTaper GOLD, WaveOne GOLD, and newly developed TruNatomy in simulated S-shaped canals. METHODS: The root canals of 60 S-shaped resin blocks were dyed using ink and photographed. The blocks were then randomly divided into three groups: group ProTaper GOLD (n = 20), WaveOne GOLD (n = 20), and TruNatomy (n = 20). The simulated canals were instrumented according to the NiTi file system and photographed again after being dyed with red ink. The pre- and post-preparation images were superimposed, and the amount of resin removed from both the mesial and distal sides of the canal measured up to 9 mm from the apical terminus, with a 1 mm increment. The preparation time was also calculated. A paired t-test was used to determine the degree of deviation at different levels within the groups. To compare the degree of transportation at different levels between the groups, one-way ANOVA and Kruskal-Wallis tests were performed according to the normality. RESULTS: TruNatomy showed a significant deviation between the mesial and distal sides of the canal only in the coronal area at 6, 7, 8, and 9 mm levels of the canal (p < 0.05). When comparing the amount of transportation in the 3 groups at 9 different levels, TruNatomy showed significantly less canal transportation than the other groups at the 3-and 5-mm levels of the canal (p < 0.05), while ProTaper GOLD showed the largest amount of transportation in the apical curved area at the 2 and 3 mm levels (p < 0.05). TruNatomy removed less resin than other groups in all sections (p < 0.05), while ProTaper GOLD removed slightly more resin than WaveOne GOLD; however, there was no significant difference (p = 0.043). Shaping time was the least for TruNatomy, followed by the WaveOne GOLD and ProTaper GOLD (p < 0.05). CONCLUSIONS: TruNatomy maintained the original apical canal curvature in S-shaped curved canals better than ProTaper GOLD and WaveOne GOLD.

Prevalence, Antibiotic-Resistance, and Virulence Characteristics of Vibrio parahaemolyticus in Restaurant Fish Tanks in Seoul, South Korea.

Vibrio parahaemolyticus is a marine bacterium that causes foodborne diarrhea. Many seafood restaurants keep live fish and shellfish in fish tanks for use in raw seafood dishes; thus, the present study aimed to investigate the prevalence, antibiotic-resistance, and virulence characteristics exhibited by V. parahaemolyticus detected in restaurant fish-tank water samples collected in Seoul, South Korea. Fish-tank water samples were collected from 69 restaurants in Seoul, and screened for the presence of V. parahaemolyticus via both a commercial detection kit, and a real-time polymerase chain reaction (RT-PCR) to detect the toxR gene. Antibiotic susceptibility and virulence determinants of V. parahaemolyticus isolates were evaluated and identified using standard disk-diffusion and RT-PCR methods, respectively. Thirty-five (50.7%) of the 69 analyzed water samples were found to be contaminated with V. parahaemolyticus. Those isolates were most often resistant to ampicillin (51.4% of isolates), followed by amikacin and tetracycline (11.4%), and ceftazidime (8.6%). Thirty (85.7%) out of the 35 isolates carried all four cytotoxicity-inducing type III secretion system 1 (T3SS1) genes [specifically, 34 (97.1%), 33 (94.3%), 35 (100%), and 32 (91.4%) isolates carried genes encoding the VP1670, VP1686, VP1689, and VP1694 T3SS1 proteins, respectively]. The type VI secretion systems (T6SS1 and T6SS2) genes were also detected in 11 (31.4%) and 27 (77.1%) isolates, respectively. However, virulence determinants such as the hemolysin (tdh and trh), urease (ureC), T3SS2α, or T3SS2ß genes that are known to be associated with enterotoxicity were not detected in all isolates. Although some known major virulence genes were not detected in the V. parahaemolyticus isolates, the results of this study indicate that restaurant fish tanks are a potential source of antibiotic-resistant V. parahaemolyticus. The presented data support the need for strict guidelines to regulate the maintenance of restaurant fish tanks to prevent antibiotic-resistant foodborne vibriosis.

Novel S-Bend Resonator Based on a Multi-Mode Waveguide with Mode Discrimination for a Refractive Index Sensor.

In this paper, a multi-mode waveguide-based optical resonator is proposed for an integrated optical refractive index sensor. Conventional optical resonators have been studied for single-mode waveguide-based resonators to enhance the performance, but mass production is limited owing to the high fabrication costs of nano-scale structures. To overcome this problem, we designed an S-bend resonator based on a micro-scale multi-mode waveguide. In general, multi-mode waveguides cannot be utilized as optical resonators, because of a performance degradation resulting from modal dispersion and an output transmission with multi-peaks. Therefore, we exploited the mode discrimination phenomenon using the bending loss, and the resulting S-bend resonator yielded an output transmission without multi-peaks. This phenomenon is utilized to remove higher-order modes efficiently using the difference in the effective refractive index between the higher-order and fundamental modes. As a result, the resonator achieved a Q-factor and sensitivity of 2.3 × 103 and 52 nm/RIU, respectively, using the variational finite-difference time-domain method. These results show that the multi-mode waveguide-based S-bend resonator with a wide line width can be utilized as a refractive index sensor.

Action observation training of community ambulation for improving walking ability of patients with post-stroke hemiparesis: a randomized controlled pilot trial.

PURPOSE: To investigate the effects of action observation training involving community-based ambulation for improving walking ability after stroke. DESIGN: Randomized, controlled pilot study. SETTING: Inpatient rehabilitation hospital. SUBJECTS: A total of 25 inpatients with post-stroke hemiparesis were randomly assigned to either the experimental group ( n = 12) or control group ( n = 13). INTERVENTION: Subjects of the experimental group watched video clips demonstrating four-staged ambulation training with a more complex environment factor for 30 minutes, three times a week for four weeks. Meanwhile, subjects of the control group watched video clips, which showed different landscape pictures. MAIN MEASURES: Walking function was evaluated before and after the four-week intervention using a 10-m walk test, community walk test, activities-specific balance confidence scale, and spatiotemporal gait measures. RESULTS: Changes in the values for the 10-m walk test (0.17 ±0.19 m/s vs. 0.05 ±0.08 m/s), community walk test (-151.42 ±123.82 seconds vs. 67.08 ±176.77 seconds), and activities-specific balance confidence (6.25 ±5.61 scores vs. 0.72 ±2.24 scores) and the spatiotemporal parameters (i.e. stride length (19.00 ±11.34 cm vs. 3.16 ±11.20 cm), single support (5.87 ±5.13% vs. 0.25 ±5.95%), and velocity (15.66 ±12.34 cm/s vs. 2.96 ±10.54 cm/s)) indicated a significant improvement in the experimental group compared with the control group. In the experimental group, walking function and ambulation confidence was significantly different between the pre- and post-intervention, whereas the control group showed a significant difference only in the 10-m walk test. CONCLUSIONS: Action observation training of community ambulation may be favorably used for improving walking function of patients with post-stroke hemiparesis.

Induction of mast cell degranulation by triterpenoidal saponins obtained from Cimicifugae rhizoma.

Cimicifugae rhizoma has been widely used as a traditional herbal medicine to treat inflammation and menopausal symptoms. In this study, we found that some of the triterpenoidal saponins purified from the ethanol extract of Cimicifugae rhizoma dramatically induced histamine release. The structure-related induction of mast cell degranulation by them and the mechanism of action were determined. ß-Hexosaminidase release in HMC-1 cells was increased in a concentration-dependent manner, with maximal 6.5- and 8.5-fold increases, by 200 µg/mL 24-epi-7,8-didehydrocimigenol-3-O-xyloside (comp 1) and cimigenol 3-O-beta-d-xyloside (comp 4) compared with those treated with phorbol 12-myristate 13-acetate and A23187 (PMACI), respectively. However, ß-hexosaminidase release was not changed by 7,8-dihydrocimigenol (comp 3), or 23-OAc-shengmanol-3-O-xyloside (comp 7). These triterpenoidal saponins changed neither the intracellular Ca(2+ )level nor the activation of PKC, both of which play essential roles in histamine release. However, cromolyn and ketotifen, membrane stabilizers, effectively inhibited the ß-hexosaminidase release induced by comp 1 or comp 4 by 39 and 45%, respectively. Collectively, xylose on the cimigenol-related backbone among triterpene glycosides isolated from Cimicifugae rhizoma may play an important role in activating mast cells and induction of degranulation partly via membrane destabilization of mast cells.

Resorptive Root Features in Mandibular Molars with Pronounced Root Divergence on Panoramic Radiographs: A Case Series.

INTRODUCTION: The visualization and understanding of the details of the root configurations and root canal structure are essential prior to root canal treatment. This study aimed to identify key indicators of pronounced root divergence between the distobuccal and distolingual roots in mandibular first molars by highlighting common features observed in panoramic radiographs. These indicators can help predict the likelihood of encountering significant root divergence before initiating endodontic treatment. CASE PRESENTATION: We present three cases in which panoramic radiographs displayed imaging features characteristic of root resorption in the distal root of the mandibular first molars. However, subsequent periapical radiographs in case 1 and cone-beam computed tomography images in cases 2 and 3 revealed that the mandibular first molars were in normal condition, with pronounced root divergence but no evidence of root resorption. CONCLUSION: Panoramic radiographs depicting mandibular molar roots with a resorptive and unclear appearance may indicate the presence of severe root divergence. In such cases, we strongly recommend additional cone-beam computed tomographic imaging to ensure precise diagnosis and facilitate optimal treatment planning for endodontic procedures.

Can the 1.8 mm transnasal biopsy forceps instead of standard 2.2 mm alter rapid urease test and histological diagnosis?

BACKGROUND AND AIM: Biopsy specimens are taken during transnasal esophagogastroduodenoscopy with 1.8 mm forceps. The aims of this study were to compare the concordance of the Campylobacter-like organism (CLO) test and histological diagnoses between biopsies taken with 1.8 mm and 2.2 mm forceps and to determine whether the concordance of the CLO test could be improved by increasing the number of specimens using 1.8 mm forceps. METHODS: A total of 200 patients were enrolled. We first performed the CLO test twice using each sample taken with both forceps in 100 patients. The CLO test was conducted three times again after confirming the difference in the CLO test between two forceps: (i) one sample with 1.8 mm forceps; (ii) two with 1.8 mm; and (iii) one with 2.2 mm in the other 100 patients. Additionally, each specimen was taken from the same gastric lesions in 200 patients for the histological diagnosis using both forceps types. RESULTS: The concordance rate of the CLO test between each sample with 1.8 mm and 2.2 mm forceps was 83% (κ-value, 0.64), and that between two samples with 1.8 mm and one with 2.2 mm was 92% (κ-value, 0.83). The concordance rate of the histological diagnosis with 1.8 and 2.2 mm was 97% (κ-value, 0.84). CONCLUSIONS: At least two samples using 1.8 mm forceps might be needed to obtain similar results on the CLO test using 2.2 mm. But, the size difference between two forceps did not influence the histological diagnosis.

TREX1 Deficiency Induces ER Stress-Mediated Neuronal Cell Death by Disrupting Ca2+ Homeostasis.

TREX1 is an exonuclease that degrades extranuclear DNA species in mammalian cells. Herein, we show a novel mechanism by which TREX1 interacts with the BiP/GRP78 and TREX1 deficiency triggers ER stress through the accumulation of single-stranded DNA and activates unfolded protein response (UPR) signaling via the disruption of the TREX1-BiP/GRP78 interaction. In TREX1 knockdown cells, the activation of ER stress signaling disrupted ER Ca2+ homeostasis via the ERO1α-IP3R1-CaMKII pathway, leading to neuronal cell death. Moreover, TREX1 knockdown dysregulated the Golgi-microtubule network through Golgi fragmentation and decreased Ac-α-tubulin levels, contributing to neuronal injury. These alterations were also observed in neuronal cells harboring a TREX1 mutation (V91M) that has been identified in hereditary spastic paraplegia (HSP) patients in Korea. Notably, this mutation leads to defects in the TREX1-BiP/GRP78 interaction and mislocalization of TREX1 from the ER and possible disruption of the Golgi-microtubule network. In summary, the current study reveals TREX1 as a novel regulator of the BiP/GRP78 interaction and shows that TREX1 deficiency promotes ER stress-mediated neuronal cell death, which indicates that TREX1 may hold promise as a therapeutic target for neurodegenerative diseases such as HSP.

Changes in liver stiffness measurement during antiviral therapy in patients with chronic hepatitis B.

BACKGROUND/AIMS: The usefulness of liver stiffness measurement (LSM) for monitoring changes in fibrosis and inflammation in chronic hepatitis B (CHB) patients receiving antiviral therapy is unknown. The aim of this study was to evaluate changes in liver stiffness and correlate them with changes in serological markers and histology in CHB patients receiving entecavir. METHODOLOGY: The study included 38 patients with CHB and 24 cirrhotic patients with CHB. All patients received entecavir for over 12 months. Liver stiffness was measured by transient elastography at baseline and after 48wks of therapy. Liver biopsy was performed on 15 patients at baseline and during therapy. RESULTS: Among 62 treated patients, 51 (82.2%) achieved HBV DNA <50 copies/mL and 43 (69%) achieved alanine aminotransferase (ALT) normalization at 48wks. The median liver stiffness value at baseline was 15.1 kPa (5.6-75.0) and decreased significantly to 8.8kPa (3.0-33.8) after 48wks. A decrease in liver stiffness value during therapy correlated significantly with decreases in albumin (r=-0.357, p=0.004), bilirubin (r=0.342, p=0.007), ALT (r=0.319, p=0.012), and aspartate aminotransferase (AST) (r=0.353, p=0.005) concentrations. Decreases in liver stiffness values correlated significantly with improvement in necroinflammatory scores. CONCLUSION: We suggest that LSM can reflect the changes of necroinflammation in patients with chronic hepatitis B receiving antiviral therapy.

Deep-learning for predicting C-shaped canals in mandibular second molars on panoramic radiographs.

OBJECTIVE: The aim of this study was to evaluate the use of a convolutional neural network (CNN) system for predicting C-shaped canals in mandibular second molars on panoramic radiographs. METHODS: Panoramic and cone beam CT (CBCT) images obtained from June 2018 to May 2020 were screened and 1020 patients were selected. Our dataset of 2040 sound mandibular second molars comprised 887 C-shaped canals and 1153 non-C-shaped canals. To confirm the presence of a C-shaped canal, CBCT images were analyzed by a radiologist and set as the gold standard. A CNN-based deep-learning model for predicting C-shaped canals was built using Xception. The training and test sets were set to 80 to 20%, respectively. Diagnostic performance was evaluated using accuracy, sensitivity, specificity, and precision. Receiver-operating characteristics (ROC) curves were drawn, and the area under the curve (AUC) values were calculated. Further, gradient-weighted class activation maps (Grad-CAM) were generated to localize the anatomy that contributed to the predictions. RESULTS: The accuracy, sensitivity, specificity, and precision of the CNN model were 95.1, 92.7, 97.0, and 95.9%, respectively. Grad-CAM analysis showed that the CNN model mainly identified root canal shapes converging into the apex to predict the C-shaped canals, while the root furcation was predominantly used for predicting the non-C-shaped canals. CONCLUSIONS: The deep-learning system had significant accuracy in predicting C-shaped canals of mandibular second molars on panoramic radiographs.

The Human TOR Signaling Regulator Is the Key Indicator of Liver Cancer Patients' Overall Survival: TIPRL/LC3/CD133/CD44 as Potential Biomarkers for Early Liver Cancers.

Recently, we reported the involvement of TIPRL/LC3/CD133 in liver cancer aggressiveness. This study assessed the human TOR signaling regulator (TIPRL)/microtubule-associated light chain 3 (LC3)/prominin-1 (CD133)/cluster of differentiation 44 (CD44) as potential diagnostic and prognostic biomarkers for early liver cancer. For the assessment, we stained tissues of human liver disease/cancer with antibodies against TIPRL/LC3/CD133/CD44/CD46, followed by confocal observation. The roles of TIPRL/LC3/CD133/CD44/CD46 in liver normal and cancer cell lines were determined by in vitro studies. We analyzed the prognostic and diagnostic potentials of TIPRL/LC3/CD133/CD44/CD46 using the receiver-operating characteristic curve, a Kaplan-Meier and uni-/multi-Cox analyses. TIPRL and LC3 were upregulated in tissues of HCCs and adult hepatocytes-derived liver diseases while downregulated in iCCA. Intriguingly, TIPRL levels were found to be critically associated with liver cancer patients' survivability, and TIPRL is the key player in liver cancer cell proliferation and viability via stemness and self-renewal induction. Furthermore, we demonstrate that TIPRL/LC3/CD133 have shown prominent efficiency for diagnosing patients with grade 1 iCCA. TIPRL/LC3/CD133/CD44 have also provided excellent potential for prognosticating patients with grade 1 iCCA and grade 1 HCCs, together with demonstrating that TIPRL/LC3/CD133/CD44 are, either individually or in conjunction, potential biomarkers for early liver cancer.

Distribution of mcr genes among carbapenem-resistant Enterobacterales clinical isolates: high prevalence of mcr-positive Enterobacter cloacae complex in Seoul, Republic of Korea.

Colistin is often used as a drug of last resort against infections caused by multi-drug-resistant Gram-negative bacteria, including carbapenem-resistant Enterobacterales (CRE). Recently, the acquisition of mobile colistin resistance (mcr) genes by CRE has become a cause for concern. This study investigated the prevalence of mcr genes in CRE isolates in Seoul, Republic of Korea. In total, 3675 CRE strains were collected from patients between 2018 and 2019, and initially screened for mcr genes using multiplex polymerase chain reaction assays. Upon the identification of mcr-harbouring strains, colistin susceptibility tests, identification of carbapenemase and ß-lactamase genes, and plasmid replicon typing were performed. Clonal analysis was conducted using pulsed-field gel electrophoresis. mcr genes were detected in 2.2% (80/3675) of CRE strains. There were three mcr-1 carriers, one mcr-4.3 carrier, one mcr-4.3/mcr-9 carrier, 58 mcr-9 carriers, one mcr-9/mcr-10 carrier and 16 mcr-10 carriers among various Enterobacterales species, of which 60 were Enterobacter cloacae complex (ECC) strains. The prevalence of mcr genes in ECC strains was 20.5%. Molecular detection confirmed that 21.3% and 13.8% of mcr-harbouring strains shared blaNDM-1 or blaKPC-2, respectively. In addition, an IncHI2 replicon was identified in 71.7% of mcr-9 strains. Comparative analysis revealed not only a notable diversity of mcr carriers, but also clonal spreading or nosocomial outbreaks of some ECC strains. These findings revealed a silent distribution of mcr genes in CRE strains with high genetic heterogeneity in Seoul, underscoring the urgent need for timely intervention to control and prevent mcr dissemination.

Dissemination of an international high-risk clone of Escherichia coli ST410 co-producing NDM-5 and OXA-181 carbapenemases in Seoul, Republic of Korea.

The rapid increase in carbapenemase-producing Enterobacterales is a global health concern. During 2017-2020, a total of 44 Escherichia coli isolates co-harbouring blaNDM-5 and blaOXA-181 were collected from patients at 17 hospitals in Seoul and characterized based on antimicrobial susceptibility, resistance genes and plasmid replicons detected using polymerase chain reaction (PCR). Clonal relatedness was estimated using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). All isolates had an identical multidrug resistance profile, including resistance to carbapenems, cephalosporins, ciprofloxacin, tetracycline, and trimethoprim/sulfamethoxazole, and susceptibility to amikacin, colistin, and tigecycline. Resistance genes (blaCTX-M-15, blaCMY-2, blaTEM-1B, blaOXA-1, aac(6')-Ib-cr, and qnrS) and plasmid replicons (IncFIA, IncFIB, and IncX3) was observed in almost all isolates. All isolates belonged to ST410 and were genetically similar (>88% similarity), with some PFGE types shared among isolates from different hospitals. Analysis of the whole genome revealed that the isolates clustered together with other strains of the international high-risk clone ST410 B4/H24RxC from other countries. These findings underline the ongoing spread of the high-risk clone of NDM-5- and OXA-181-producing E. coli ST410 B4/H24RxC among hospitals in Seoul. Continuous monitoring and implementation of infection control measures are crucial to track and prevent further spread of these resistant strains.

Corrigendum: Characteristics of Genetic Variations Associated With Lennox-Gastaut Syndrome in Korean Families.

[This corrects the article DOI: 10.3389/fgene.2020.590924.].

Oroxylin A, a flavonoid, stimulates adult neurogenesis in the hippocampal dentate gyrus region of mice.

Previously, we reported the cognitive enhancing effects of oroxylin A in unimpaired mice and its memory ameliorating activity in various memory impaired mice. To elucidate the mechanism mediating the cognitive effects of oroxylin A, this study examined the consequences of oroxylin A administration on neurogenesis in the hippocampal dentate gyrus using immunostaining for 5-bromo-2-deoxyuridine (BrdU) incorporation. In addition, we determined whether the new cells adopted a neuronal or glial fate by examining the co-localization of BrdU staining with neuronal or glial markers. Administration of oroxylin A in a dose-dependent and time-dependent manner increased the number of BrdU-incorporating cells. Moreover, the percentage of BrdU-incorporating cells co-localized with neuronal markers, neuronal nuclei, was significantly increased by the oroxylin A administration. These results suggest that the increased neurogenesis induced by the administration of oroxylin A could be, at least in part, associated with its positive effects on cognitive processing.

Rates of early surgery and associated risk factors in Crohn's disease.

BACKGROUND/AIMS: The individual course of Crohn's disease is diverse, and some patients may require bowel resection. The aims of this study were to determine the early surgery rate of Crohn's disease and to identify risk factors associated with early surgery in Korea. METHODS: Ninety six patients with Crohn's disease (68 men; median age at the time of diagnosis: 25 years), who had been followed up more than a year, were retrospectively analyzed. Early surgery was defined as a bowel operation for Crohn's disease or its complications occurring within 3 years from diagnosis. Early surgery rate and risk factors for early surgery were identified. RESULTS: Fifteen patients (15.6%) underwent early surgery. The cumulative surgery rate was 8.6% after 6 months, 11.9% after 12 months, 14.1% after 18 months, and 16.7% after 24 to 36 months. Multivariate analysis revealed penetrating or stricturing behavior to be an independent risk factor for early surgery (p<0.001, Exp (B)=2.97 CI 1.39-6.37). CONCLUSIONS: The cumulative early surgery rate in Korean patients seems to be lower than Western patients. Penetrating or stricturing behavior is significantly associated with early surgery, requiring early aggressive medical treatments.

[Add on lamivudine to adefovir monotherapy for the treatment of lamivudine-resistant chronic hepatitis B patients].

BACKGROUND/AIMS: Add on adefovir (ADV) to ongoing lamivudine (LAM) has been recommended as a standard therapy for the treatment of LAM resistance. In the past, switch to ADV monotherapy was suggested as an option for the treatment of LAM resistance, leading to frequent development of ADV resistance. However, ADV monotherapy has been still used in LAM-resistant patients because of low cost in Korea. The aims of this study were to evaluate the virologic response and virologic breakthrough during adding on LAM in LAM-resistant patients receiving ADV monotherapy. METHODS: The study population comprised 99 patients with LAM-resistance. We divided them into 3 groups (Group 1: switch to ADV monotherapy, N=58, Group 2: add on ADV to ongoing LAM, N=25, Group 3: add on LAM to ADV monotherapy, N=16). HBV DNA levels were assessed at baseline and every 3 months during therapy. Serum HBV DNA levels were measured by bDNA assay or the COBAS TaqMan(TM) HBV test. RESULTS: The median treatment duration for group 1, group 2, and group 3 was 42.0, 20.6, and 31.8 (18.7 mon. of ADV13.1 mon. of LAM) months, respectively. Cumulative rate of virologic breakthrough in group 1 was 5.2%, 19.0%, and 25.9% at 12, 24, and 36 months of treatment, respectively. Virologic breakthrough was not detected in group 2 and group 3 (p=0.016, group 1 vs. group 2 or 3). In group 3, median serum HBV DNA levels were 4.22 log10 copies/mL prior to LAM administration. Median serum HBV DNA changes from baseline (log10 copies/mL) were -0.91, -1.93, -1.87 and -1.74 at week 12, 24, 36 and 48, respectively. CONCLUSIONS: Later add on LAM to ADV monotherapy prevented the development of ADV resistance in patients with LAM resistance effectively, comparable to ADV add on to continuing LAM therapy.