Publications by authors named "Jaemin Lee"

161 Publications

Linezolid-induced black hairy tongue in a patient with multidrug-resistant tuberculosis: A case report.

Sci Prog 2021 Jul-Sep;104(3):368504211042982

Department of Internal Medicine, 220312Pusan National University Hospital, Republic of Korea.

The revised World Health Organization guidelines on multidrug-resistant tuberculosis include linezolid in the core drugs group. Consequently, the use of linezolid for patients with multidrug-resistant tuberculosis is increasing. Common adverse events of long-term linezolid use include bone marrow suppression and neuropathies. However, there is limited information on a rare adverse event, black hairy tongue. Here, we report a case of linezolid-induced black hairy tongue in a patient with multidrug-resistant tuberculosis. The etiology, pathogenesis, diagnosis, and treatment of black hairy tongue are also discussed.
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http://dx.doi.org/10.1177/00368504211042982DOI Listing
September 2021

Antiobesity therapeutics with complementary dual-agonist activities at glucagon and glucagon-like peptide 1 receptors.

Diabetes Obes Metab 2021 Sep 6. Epub 2021 Sep 6.

Department of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea.

Aim: To develop more effective and long-lasting antiobesity and antidiabetic therapeutics by employing novel chemical modifications of glucagon-like peptide-1 receptor (GLP-1R) agonists.

Methods: We constructed novel unimolecular dual agonists of GLP-1R and glucagon receptor prepared by linking sEx-4 and native glucagon (GCG) via lysine or triazole [sEx4-GCG(K) and sEx4-GCG(T), respectively] and evaluated their antiobesity and antidiabetic efficacy in the diabetic and obese mouse model.

Results: Both sEx4-GCG(K) and sEx4-GCG(T) showed the beneficial metabolic effects of GLP-1 and glucagon: they promoted weight loss and ameliorated insulin resistance and hepatic steatosis. They also increased thermogenesis in brown adipose tissue, and lipolysis and β-oxidation in white adipose tissue, with concomitant suppression of lipogenesis. Furthermore, both dual agonists activated the 5'-AMP-activated protein kinase signalling pathway and prevented palmitate-induced oxidative stress in skeletal muscle cells.

Conclusion: Through their complementary dual agonism, sEx4-GCG(T) and sEx4-GCG(K) induce more marked weight loss and metabolic improvements than conventional agonists, and could be developed as novel therapeutic agents for the treatment of obesity and associated metabolic disorders in humans.
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http://dx.doi.org/10.1111/dom.14546DOI Listing
September 2021

Extracellular vesicles from in vivo liver tissue accelerate recovery of liver necrosis induced by carbon tetrachloride.

J Extracell Vesicles 2021 Aug 11;10(10):e12133. Epub 2021 Aug 11.

Department of Life Sciences Pohang University of Science and Technology (POSTECH) Pohang Republic of Korea.

Extracellular vesicles (EVs) are nano-sized vesicles composed of proteolipid bilayers carrying various molecular signatures of the cells. As mediators of intercellular communications, EVs have gained great attention as new therapeutic agents in the field of nanomedicine. Therefore, many studies have explored the roles of cell-derived EVs isolated from cultured hepatocytes or stem cells as inducer of liver proliferation and regeneration under various pathological circumstances. However, study investigating the role of EVs directly isolated from liver tissue has not been performed. Herein, to understand the pathophysiological role and to investigate the therapeutic potential of in vivo liver EVs, we isolated EVs from both normal and carbon tetrachloride (CCl)-induced damaged in vivo liver tissues. The in vivo EVs purified from liver tissues display typical features of EVs including spherical morphology, nano-size, and enrichment of tetraspanins. Interestingly, administration of both normal and damaged liver EVs significantly accelerated the recovery of liver tissue from CCl-induced hepatic necrosis. This restorative action was through the induction of hepatocyte growth factor at the site of the injury. These results suggest that not only normal liver EVs but also damaged liver EVs play important pathophysiological roles of maintaining homeostasis after tissue damage. Our study, therefore, provides new insight into potentially developing in vivo EV-based therapeutics for preventing and treating liver diseases.
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http://dx.doi.org/10.1002/jev2.12133DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8357636PMC
August 2021

Pathophysiological Roles of Neuro-Immune Interactions between Enteric Neurons and Mucosal Mast Cells in the Gut of Food Allergy Mice.

Cells 2021 06 23;10(7). Epub 2021 Jun 23.

Division of Gastrointestinal Pathophysiology, Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.

Recently, the involvement of the nervous system in the pathology of allergic diseases has attracted increasing interest. However, the precise pathophysiological role of enteric neurons in food allergies has not been elucidated. We report the presence of functional high-affinity IgE receptors (FcεRIs) in enteric neurons. FcεRI immunoreactivities were observed in approximately 70% of cholinergic myenteric neurons from choline acetyltransferase-eGFP mice. Furthermore, stimulation by IgE-antigen elevated intracellular Ca concentration in isolated myenteric neurons from normal mice, suggesting that FcεRIs are capable of activating myenteric neurons. Additionally, the morphological investigation revealed that the majority of mucosal mast cells were in close proximity to enteric nerve fibers in the colonic mucosa of food allergy mice. Next, using a newly developed coculture system of isolated myenteric neurons and mucosal-type bone-marrow-derived mast cells (mBMMCs) with a calcium imaging system, we demonstrated that the stimulation of isolated myenteric neurons by veratridine caused the activation of mBMMCs, which was suppressed by the adenosine A3 receptor antagonist MRE 3008F20. Moreover, the expression of the adenosine A3 receptor gene was detected in mBMMCs. Therefore, in conclusion, it is suggested that, through interaction with mucosal mast cells, IgE-antigen-activated myenteric neurons play a pathological role in further exacerbating the pathology of food allergy.
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http://dx.doi.org/10.3390/cells10071586DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8305700PMC
June 2021

Field Assessment of Six Point-Mutations in SDH Subunit Genes Conferring Varying Resistance Levels to SDHIs in spp.

Plant Dis 2021 Jun 4;105(6):1685-1691. Epub 2021 May 4.

Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, U.S.A.

Dollar spot, caused by spp. (formerly F.T. Bennett), is the most economically important turfgrass disease causing considerable damage on golf courses. While cultural practices are available for reducing dollar spot infection, chemical fungicide use is often necessary for maintaining optimal turf quality. Since the release of boscalid in 2003, the succinate dehydrogenase inhibitor (SDHI) class has become an invaluable tool for managing dollar spot. However, resistance to this class has recently been reported in spp. and many other plant pathogenic fungi. After SDHI field failure on four golf courses and one university research plot, a total of six unique SDH mutations conferring differential in vitro sensitivities to SDHIs have been identified in spp. In 2018 and 2019, turf research plots were inoculated with sensitive, non-mutated isolates of spp., as well as resistant isolates harboring each unique identified mutation. Fungicide efficacy trials were conducted on inoculated plots to assess differential sensitivity to five SDHI active ingredients (boscalid, fluxapyroxad, isofetamid, fluopyram, and pydiflumetofen) across mutations under field conditions. Results indicate unique mutations are associated with distinct SDHI field efficacy profiles as shown in in-vitro sensitivity assays. Isolate populations with B subunit mutations (H267Y/R) were more sensitive to fluopyram, whereas isolate populations with C subunit mutations (C-G91R, C-G150R) showed resistance to all SDHIs tested. Mutation-associated differential sensitivity observed under field conditions indicates a need for a nation-wide survey and frequent monitoring of SDHI sensitivity of dollar spot populations on golf courses in the USA. Further, the information gained from this study will be useful in providing sustainable management recommendations for controlling site-specific resistant populations of spp.
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http://dx.doi.org/10.1094/PDIS-06-20-1344-REDOI Listing
June 2021

Digital Assessment of Gingival Dimensions of Healthy Periodontium.

J Clin Med 2021 04 7;10(8). Epub 2021 Apr 7.

Department of Periodontology, College of Dentistry, Dankook University, Cheonan-si 31116, Korea.

The aim of the present study was to re-visit the gingival dimension using digital scanning in a healthy Korean population. Forty-eight periodontally healthy volunteers (38 males and 10 females, mean age: 24.3 ± 2.2 years) were included. The mucogingival junction was highlighted using 2.5% diluted iodine solution. Then, the facial gingiva and mucosa of both jaws were digitally scanned using an intraoral digital scanner. Using computer software and periodontal probing, the heights and areas of keratinized gingiva (KG) and attached gingiva (AG) were measured. Similar distribution patterns in the gingival heights were noted in the maxilla and mandible. The maxilla showed substantially greater gingival values than the mandible. The heights of the KG and AG were notably smaller on the mandibular first premolar (2.37 mm and 1.07 mm, median value) and second molar (3.28 mm and 1.78 mm) than on the other teeth. The area of the KG was the largest in the canine (63.74 mm and 46.85 mm) and first molar (64.14 mm and 58.82 mm) in each jaw. Mandibular first and second molars, mandibular canine, and maxillary canine showed the highest value of the area under the receiver operation characteristics curve (>0.7) for differentiating between males and females. The gingival dimensions recorded using intraoral scanner demonstrated similar distribution patterns as in previous studies.
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http://dx.doi.org/10.3390/jcm10081550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8068027PMC
April 2021

Pancreatic cancer induces muscle wasting by promoting the release of pancreatic adenocarcinoma upregulated factor.

Exp Mol Med 2021 Mar 17;53(3):432-445. Epub 2021 Mar 17.

Department of Health Sciences, The Graduate School of Dong-A University, Busan, 49315, Republic of Korea.

Cancer cachexia is a highly debilitating condition characterized by weight loss and muscle wasting that contributes significantly to the morbidity and mortality of pancreatic cancer. The factors that induce cachexia in pancreatic cancer are largely unknown. We previously showed that pancreatic adenocarcinoma upregulated factor (PAUF) secreted by pancreatic cancer cells is responsible for tumor growth and metastasis. Here, we analyzed the relation between pancreatic cancer-derived PAUF and cancer cachexia in mice and its clinical significance. Body weight loss and muscle weight loss were significantly higher in mice with Panc-1/PAUF tumors than in those with Panc-1/Mock tumors. Direct administration of rPAUF to muscle recapitulated tumor-induced atrophy, and a PAUF-neutralizing antibody abrogated tumor-induced muscle wasting in Panc-1/PAUF tumor-bearing mice. C2C12 myotubes treated with rPAUF exhibited rapid inactivation of Akt-Foxo3a signaling, resulting in Atrogin1/MAFbx upregulation, myosin heavy chain loss, and muscle atrophy. The neutrophil-to-lymphocyte ratio and body weight loss were significantly higher in pancreatic cancer patients with high PAUF expression than in those with low PAUF expression. Analysis of different pancreatic cancer datasets showed that PAUF expression was significantly higher in the pancreatic cancer group than in the nontumor group. Analysis of The Cancer Genome Atlas data found associations between high PAUF expression or a high DNA copy number and poor overall survival. Our data identified tumor-secreted circulating PAUF as a key factor of cachexia, causing muscle wasting in mice. Neutralizing PAUF may be a useful therapeutic strategy for the treatment of pancreatic cancer-induced cachexia.
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http://dx.doi.org/10.1038/s12276-021-00582-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8080719PMC
March 2021

Anti-Inflammatory Effect of on Ethanol-Induced Gastric Ulcer: Analytical, In Vitro and In Vivo Studies for the Identification of Action Mechanism and Active Compounds.

Plants (Basel) 2021 Feb 9;10(2). Epub 2021 Feb 9.

Korean Medicine, Gachon University, Seongnam-si, Gyeonggi-do 13120, Korea.

is widely used as traditional medicine in East Asia. However, its effects against inflammation and gastric ulcers have not been reported yet. We analyzed anti-inflammatory activity and its molecular mechanisms of using RAW264.7 cells line, then evaluated the curative efficacy in rats with acute gastric ulcers. Nitric oxide and IL-6 production was measured using Griess reagent and an ELISA kit. Inducible nitric oxide synthase (iNOS), interleukin (IL)-6, and mucin (MUC)1, MUC5AC, and MUC6 mRNA were determined by SYBR Green or Taqman qRT-PCR methods. The phosphorylation of ERK, JNK, p38, and c-Jun protein were detected by western blotting. RW0117 inhibited LPS-induced NO and IL-6 production. The mRNA levels of iNOS and IL-6 were strongly suppressed. The phosphorylation of ERK, JNK, and c-Jun decreased by treatment with RW0117. Oral administration of RW0117 recovered the amount of mucin mRNA and protein level that was decreased due to gastric ulcers by HCl-EtOH. exhibited strong anti-inflammatory effects and contributed to the modulation of HCl-EtOH-induced gastric ulcer in rats.
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http://dx.doi.org/10.3390/plants10020332DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7914715PMC
February 2021

Correction of malrotation in two-stage breast reconstruction: outcomes and risk-factor analysis.

J Plast Surg Hand Surg 2021 Feb 20;55(1):6-12. Epub 2021 Jan 20.

Department of Plastic and Reconstructive Surgery, Korea University Anam Hospital, Seoul, Korea.

Although an anatomical implant is no longer recommended in practice, frequent use of the implants in the past decade left apprehension to surgeons, and malrotation is one of the concerns. However, a limited amount of literature has focused on malrotation to date, especially in breast reconstruction, and there also exists a lack of consensus regarding the correction of malrotation. Given that implant-based reconstruction has increased in frequency and there remain many potential patients who have used earlier models of anatomical implants, this study sought to analyze predisposing risk factors and approaches to correct implant malrotation. A total of 132 implants in 118 patients who underwent expander/implant reconstruction were identified and retrospectively reviewed. Seventeen (12.9%) implants showed malrotation. The results of multivariate logistic regression revealed that tissue expander malrotation in the first stage and capsular contracture were significant risk factors associated with malrotation in two-stage implant-based breast reconstruction (both  < 0.001). When a patient presents with malrotation, it is recommended that the implant be changed to a round type if a patient has multiple risk factors because malrotation tends to recur after correction. Also, even when using a round implant during two-stage breast reconstruction, additional care should be adopted for those who experienced rotation after expander insertion.
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http://dx.doi.org/10.1080/2000656X.2020.1817752DOI Listing
February 2021

The Hybrid Latissimus Dorsi Flap in Immediate Breast Reconstruction: A Comparative Study With the Abdominal-Based Flap.

Ann Plast Surg 2021 04;86(4):394-399

From the Department of Plastic and Reconstructive Surgery, Korea University Anam Hospital, Seoul, Korea.

Purpose: The implant-enhanced latissimus dorsi (LD) flap, or a hybrid LD flap, is widely used in certain indications, even though abdominal-based flaps are now considered the gold standard of autologous breast reconstruction. However, few articles distinguish the hybrid LD flap from traditional LD flaps, and not many articles have compared the surgical outcomes, with the abdominal-based flap procedure, especially in the area of immediate breast reconstruction. In addition, it is often overlooked that the reported esthetic comparisons are based on different populations and contralateral balancing procedures (CBPs). Thus, this study aimed to review the reconstruction outcomes and to compare the variable-matched esthetic outcomes between 2 groups.

Methods: A retrospective review of patients who underwent immediate breast reconstruction with either a hybrid LD flap or an abdominal-based free flap and had completed at least 2 years of follow-up visits was carried out. The patient demographics, oncologic data, breast parameters, and postoperative outcomes were compared across the entire patient group. The body mass index (BMI)- and CBP-matched cohort was randomly selected and assessed using the Aesthetic Outcome parameter of the Aesthetic Item Scale.

Result: Thirty-eight hybrid LD flap and 51 abdominal-based free flap procedures were included. The hybrid LD group showed a shorter operation time (330 ± 260 minutes vs 550 ± 480 minutes, respectively; P < 0.01), and fewer patients in the hybrid LD group underwent additional revision surgeries (7 [18.4%] vs 20 [39.2%], respectively; P < 0.01). Other complication rates were not significantly different between groups. A BMI- and CBP-matched esthetic analysis revealed that the hybrid LD group showed superior results in symmetry (Mann-Whitney U test, P = 0.047).

Conclusions: The LD flap in combination with an implant remains a viable option in immediate breast reconstruction and had a similar complication profile while having a shorter operative time compared with the abdominal-based autologous breast reconstruction procedure. If properly used in certain populations, hybrid LD flaps may offer superior results regarding symmetry over the abdominal-based flap procedure.
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http://dx.doi.org/10.1097/SAP.0000000000002565DOI Listing
April 2021

Evaluation of Anti-Colitis Effect of KM1608 and Biodistribution of Dehydrocostus Lactone in Mice Using Bioimaging Analysis.

Plants (Basel) 2020 Sep 10;9(9). Epub 2020 Sep 10.

College of Korean Medicine, Gachon University, Seongnam-si, Gyeonggi-do 13120, Korea.

Inflammatory bowel disease (IBD) is a chronic relapsing disorder modulated by numerous factors. Recent failures of drugs targeting single factors suggest that multitargeting drugs could be useful for the treatment of IBD. Natural medicines may be an alternative option for the treatment of IBD, owing to the complex nature of the disease. However, most natural medicines have poor in vitro and in vivo translational potential because of inadequate pharmacokinetic study. KM1608, a mixture of the medicinal plants , , and , was examined for its anti-colitis effects and biodistribution using bioimaging. Dehydrocostus lactone, as a marker compound, was analyzed to assess the biodistribution of KM1608. KM1608 significantly attenuated the disease activity of dextran sodium sulfate-induced colitis in mice and suppressed inflammatory mediators such as myeloperoxidase, proinflammatory cytokines (TNF-α and IL-6), and the Th2-type cytokine IL-4 in the colon. Optical fluorescence imaging revealed that KM1608 was distributed in the intestinal area as a target organ. Collectively, our findings suggest that KM1608 is a potential therapeutic formulation for IBD.
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http://dx.doi.org/10.3390/plants9091175DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7570101PMC
September 2020

Sequential Organ Failure Assessment score as a predictor of mortality in ventilated patients with multidrug-resistant bacteremia.

Acute Crit Care 2020 Aug 31;35(3):169-178. Epub 2020 Aug 31.

Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea.

Background: The occurrence of multidrug-resistant (MDR) bacteremia in ventilated patients may be associated with a high mortality rate. We evaluated whether Sequential Organ Failure Assessment (SOFA) score on the day of bacteremia could predict 90-day mortality in these patients.

Methods: Data were obtained retrospectively from 202 patients (male, 60.4%; median age, 64 years) hospitalized at a single university-affiliated tertiary care hospital. All adult patients who had were ventilated and had one of the following six MDR bacteremias between March 2011 and February 2018 were enrolled: methicillin-resistant Staphylococcus aureus, extended-spectrum β-lactamase-producing Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia), carbapenem-resistant Gram-negative rods (Acinetobacter baumannii and Pseudomonas aeruginosa), or vancomycin-resistant Enterococcus faecium.

Results: The overall 90-day mortality rate after the day of bacteremia was 59.9%. The areas under the receiver operating characteristic curves for the SOFA and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were 0.732 (95% confidence interval [CI], 0.666 to 0.792; P<0.001) and 0.662 (95% CI, 0.593 to 0.727; P<0.001), respectively, with no difference between the two (P=0.059). Also, the cutoff value of the SOFA score was 9 (based on Youden's index). Multivariate Cox regression analysis showed that this cut-off value was significantly associated with higher mortality rate (hazard ratio, 2.886; 95% CI, 1.946 to 4.221; P<0.001).

Conclusions: SOFA score measured on the day of bacteremia may be a useful prognostic indicator of 90-day mortality in ventilated patients with MDR bacteremia.
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http://dx.doi.org/10.4266/acc.2020.00143DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7483015PMC
August 2020

Hot-Melt 3D Extrusion for the Fabrication of Customizable Modified-Release Solid Dosage Forms.

Pharmaceutics 2020 Aug 5;12(8). Epub 2020 Aug 5.

College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, Jinju 52828, Korea.

In this work, modified-release solid dosage forms were fabricated by adjusting geometrical properties of solid dosage forms through hot-melt 3D extrusion (3D HME). Using a 3D printer with air pressure driving HME system, solid dosage forms containing ibuprofen (IBF), polyvinyl pyrrolidone (PVP), and polyethylene glycol (PEG) were printed by simultaneous HME and 3D deposition. Printed solid dosage forms were evaluated for their physicochemical properties, dissolution rates, and floatable behavior. Results revealed that IBF content in the solid dosage form could be individualized by adjusting the volume of solid dosage form. IBF was dispersed as amorphous state with enhanced solubility and dissolution rate in a polymer solid dosage form matrix. Due to absence of a disintegrant, sustained release of IBF from printed solid dosage forms was observed in phosphate buffer at pH 6.8. The dissolution rate of IBF was dependent on geometric properties of the solid dosage form. The dissolution rate of IBF could be modified by merging two different geometries into one solid dosage form. In this study, the 3D HME process showed high reproducibility and accuracy for preparing dosage forms. API dosage and release profile were found to be customizable by modifying or combining 3D modeling.
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http://dx.doi.org/10.3390/pharmaceutics12080738DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7464107PMC
August 2020

A Rapid Molecular Detection System for SdhB and SdhC Point Mutations Conferring Differential Succinate Dehydrogenase Inhibitor Resistance in Populations.

Plant Dis 2021 Mar 13;105(3):660-666. Epub 2021 Jan 13.

Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, U.S.A.

Dollar spot, caused by the ascomycete fungus (formerly ), is one of the most resource-demanding diseases on amenity turfgrasses in North America. Differential resistance to the succinate dehydrogenase inhibitor (SDHI) fungicide class, conferred by singular point mutations on the B, C, and SdhD subunits of the succinate dehydrogenase enzyme (SDH), has been reported in dollar spot as well as many other plant-pathogenic fungal diseases. Four unique mutations were previously reported from field isolates collected from two different cool-season golf courses in Japan and Rhode Island: an amino acid substitution H267Y and a silent mutation (CTT to CTC) at codon 181 on the B subunit gene, and amino acid substitutions G91R and G150R on the C subunit gene. To properly diagnose and monitor SDHI resistance in the field, a rapid detection system for known mutations is crucial. As part of this study, additional SDHI-resistant isolates were collected from Rutgers University research plots and in vitro sensitivity to four SDHI active ingredients was assessed. B, C, and SdhD subunits of these isolates were sequenced to reveal an additional mutation on the B subunit gene, H267R, not previously observed in Clarireedia. Cleaved amplified polymorphic sequence (CAPS) and derived CAPS molecular markers were developed to detect five mutations conferring SDHI resistance in isolates and validated using samples from two additional golf courses in Connecticut and Wisconsin experiencing SDHI field failure. This PCR-based molecular detection system will be useful for continued monitoring, assessment, and delay of SDHI resistance in the field.
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http://dx.doi.org/10.1094/PDIS-04-20-0724-REDOI Listing
March 2021

Indoor dust extracellular vesicles promote cancer lung metastasis by inducing tumour necrosis factor-α.

J Extracell Vesicles 2020 19;9(1):1766821. Epub 2020 May 19.

Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea.

Indoor pollutants are important problems to public health. Among indoor pollutants, indoor dust contains extracellular vesicles (EVs), which are associated with pulmonary inflammation. However, it has not been reported whether indoor dust EVs affect the cancer lung metastasis. In this study, we isolated indoor dust EVs and investigated their roles in cancer lung metastasis. Upon intranasal administration, indoor dust EVs enhanced mouse melanoma lung metastasis in a dose-dependent manner in mice. Pre-treatment or co-treatment of indoor dust EVs significantly promoted melanoma lung metastasis, whereas post-treatment of the EVs did not. In addition, the lung lysates from indoor dust EV-treated mice significantly increased tumour cell migration . We observed that tumour necrosis factor-α played important roles in indoor dust EV-mediated promotion of tumour cell migration and cancer lung metastasis . Furthermore, EVs, the main components of indoor dust EVs, and indoor dust EVs showed comparable effects in promoting tumour cell migration and cancer lung metastasis . Taken together, our results suggest that indoor dust EVs, at least partly contributed by EVs, are potential promoting agents of cancer lung metastasis.
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http://dx.doi.org/10.1080/20013078.2020.1766821DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7301719PMC
May 2020

Plasma proteomic profiling of young and old mice reveals cadherin-13 prevents age-related bone loss.

Aging (Albany NY) 2020 05 12;12(9):8652-8668. Epub 2020 May 12.

Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea.

The blood exhibits a dynamic flux of proteins that are secreted by the tissues and cells of the body. To identify novel aging-related circulating proteins, we compared the plasma proteomic profiles of young and old mice using tandem mass spectrometry. The expression of 134 proteins differed between young and old mice. We selected seven proteins that were expressed at higher levels in young mice, and confirmed their plasma expression in immunoassays. The plasma levels of anthrax toxin receptor 2 (ANTXR2), cadherin-13 (CDH-13), scavenger receptor cysteine-rich type 1 protein M130 (CD163), cartilage oligomeric matrix protein (COMP), Dickkopf-related protein 3 (DKK3), periostin, and secretogranin-1 were all confirmed to decrease with age. We then investigated whether any of the secreted proteins influenced bone metabolism and found that CDH-13 inhibited osteoclast differentiation. CDH 13 treatment suppressed the receptor activator of NF-κB ligand (RANKL) signaling pathway in bone marrow-derived macrophages, and intraperitoneal administration of CDH-13 delayed age-related bone loss in the femurs of aged mice. These findings suggest that low plasma CDH-13 expression in aged mice promotes aging-associated osteopenia by facilitating excessive osteoclast formation. Thus, CDH-13 could have therapeutic potential as a protein drug for the prevention of osteopenia.
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http://dx.doi.org/10.18632/aging.103184DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7244053PMC
May 2020

Asparaginyl-tRNA Synthetase, a Novel Component of Hippo Signaling, Binds to Salvador and Enhances Yorkie-Mediated Tumorigenesis.

Front Cell Dev Biol 2020 5;8:32. Epub 2020 Feb 5.

Metabolism and Neurophysiology Research Group, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea.

Aminoacyl-tRNA synthetases (ARSs), which are essential for protein translation, were recently shown to have non-translational functions in various pathological conditions including cancer. However, the molecular mechanism underlying the role of ARSs in cancer remains unknown. Here, we demonstrate that asparaginyl-tRNA synthetase (NRS) regulates Yorkie-mediated tumorigenesis by binding to the Hippo pathway component Salvador. and the NRS inhibitor tirandamycin B (TirB) suppressed Yorkie-mediated tumor phenotypes in . Genetic analysis showed that interacted with Salvador, and activated Hippo target genes by regulating Yorkie phosphorylation. Biochemical analyses showed that NRS blocked Salvador-Hippo binding by interacting directly with Salvador, and TirB treatment inhibited NRS-Salvador binding. YAP target genes were upregulated in a mammalian cancer cell line with high expression of NRS, whereas TirB treatment suppressed cancer cell proliferation. These results indicate that NRS regulates tumor growth by interacting with Salvador in the Hippo signaling pathway.
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http://dx.doi.org/10.3389/fcell.2020.00032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7014954PMC
February 2020

Size-dependent fluorescence of conjugated polymer dots and correlation with the fluorescence in solution and in the solid phase of the polymer.

Nanoscale 2020 Jan 9;12(4):2492-2497. Epub 2020 Jan 9.

Organic and Optoelectronic Materials Laboratory, Department of Organic Materials Engineering, Chungnam National University, Daejeon 34134, Korea.

Three conjugated polymers (CPs) were synthesized to obtain CPs with the same backbone but with different compositions of repeat units (phenylene and benzoselenadiazole (BSD)). The dominant composition of phenylene units and a smaller amount of BSD in the CP backbone enabled the CPs to emit different fluorescence colors according to their condition (solution or solid), which was caused by the difference in intermolecular electron transfer between CP backbones. Inspired by this, we fabricated polymer dots (Pdots) with various sizes using the CPs to control the number of CP chains within a spherical Pdot. This implied that smaller Pdots, where the chance of intermolecular electron transfer would be at a minimum, would accommodate fewer polymer chains than larger ones. The minimum chance for intermolecular electron transfer resulted in a short-wavelength emission, which was the identical emission color encountered in liquid CP solution. A more frequent intermolecular electron transfer was expected in larger Pdots, exhibiting long-wavelength emission, which was the same as observed in solid CPs. White-light-emitting Pdots that showed Commission Internationale de 1'Eclairage (CIE) coordinates of (0.34, 0.31) were fabricated simply by controlling the Pdot size.
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http://dx.doi.org/10.1039/c9nr09380jDOI Listing
January 2020

Protective Effect of Panaxynol Isolated from against Cisplatin-Induced Renal Damage: In Vitro and In Vivo Studies.

Biomolecules 2019 12 17;9(12). Epub 2019 Dec 17.

College of Korean Medicine, Gachon University, Seongnam 13120, Korea.

Polyacetylenic compounds isolated from species are comprised of non-polar C17 compounds, exhibiting anti-inflammatory, antitumor, and antifungal activities. Panaxynol represents the major component of the essential oils of ginseng. We investigated whether panaxynol isolated from (Vietnamese ginseng, VG) could prevent cisplatin-induced renal damage induced in vitro and in vivo. Cisplatin-induced apoptotic cell death was observed by staining with annexin V conjugated with Alexa Fluor 488, and western blotting evaluated the molecular mechanism. Panaxynol at concentrations above 0.25 μM prevented cisplatin-induced LLC-PK1 porcine renal proximal tubular cell death. LLC-PK1 cells treated with cisplatin demonstrated an increase in apoptotic cell death, whereas pretreatment with 2 and 4 μM panaxynol decreased this effect. Cisplatin demonstrated a marked increase in the phosphorylation of c-Jun N-terminal kinase (JNK), P38, and cleaved caspase-3. However, pretreatment with 2 and 4 μM panaxynol reversed the upregulated phosphorylation of JNK, P38, and the expression of cleaved caspase-3. We confirmed that the protective effect of panaxynol isolated from in LLC-PK1 cells was at least partially mediated by reducing the cisplatin-induced apoptotic damage. In the animal study, panaxynol treatment ameliorated body weight loss and blood renal function markers and downregulated the mRNA expression of inflammatory mediators.
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http://dx.doi.org/10.3390/biom9120890DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6995609PMC
December 2019

Cellular Stress-Modulating Drugs Can Potentially Be Identified by in Silico Screening with Connectivity Map (CMap).

Int J Mol Sci 2019 Nov 9;20(22). Epub 2019 Nov 9.

Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Korea.

Accompanied by increased life span, aging-associated diseases, such as metabolic diseases and cancers, have become serious health threats. Recent studies have documented that aging-associated diseases are caused by prolonged cellular stresses such as endoplasmic reticulum (ER) stress, mitochondrial stress, and oxidative stress. Thus, ameliorating cellular stresses could be an effective approach to treat aging-associated diseases and, more importantly, to prevent such diseases from happening. However, cellular stresses and their molecular responses within the cell are typically mediated by a variety of factors encompassing different signaling pathways. Therefore, a target-based drug discovery method currently being used widely (reverse pharmacology) may not be adequate to uncover novel drugs targeting cellular stresses and related diseases. The connectivity map (CMap) is an online pharmacogenomic database cataloging gene expression data from cultured cells treated individually with various chemicals, including a variety of phytochemicals. Moreover, by querying through CMap, researchers may screen registered chemicals in silico and obtain the likelihood of drugs showing a similar gene expression profile with desired and chemopreventive conditions. Thus, CMap is an effective genome-based tool to discover novel chemopreventive drugs.
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http://dx.doi.org/10.3390/ijms20225601DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6888006PMC
November 2019

Nanoscale Visualization and Multiscale Electrochemical Analysis of Conductive Polymer Electrodes.

ACS Nano 2019 Nov 7;13(11):13271-13284. Epub 2019 Nov 7.

Department of Materials Science and Engineering , University of Arizona , Tucson , Arizona 85721 , United States.

Conductive polymers are exceptionally promising for modular electrochemical applications including chemical sensors, bioelectronics, redox-flow batteries, and photoelectrochemical systems due to considerable synthetic tunability and ease of processing. Despite well-established structural heterogeneity in these systems, conventional macroscopic electroanalytical methods-specifically cyclic voltammetry-are typically used as the primary tool for structure-property elucidation. This work presents an alternative correlative multimicroscopy strategy. Data from laboratory and synchrotron-based microspectroscopies, including conducting-atomic force microscopy and synchrotron nanoscale infrared spectroscopy, are combined with potentiodynamic movies of electrochemical fluxes from scanning electrochemical cell microscopy (SECCM) to reveal the relationship between electrode structure and activity. A model conductive polymer electrode system of tailored heterogeneity is investigated, consisting of phase-segregated domains of poly(3-hexylthiophene) (P3HT) surrounded by contiguous regions of insulating poly(methyl methacrylate) (PMMA), representing an ultramicroelectrode array. Isolated domains of P3HT are shown to retain bulk-like chemical and electronic structure when blended with PMMA and possess approximately equivalent electron-transfer rate constants compared to pure P3HT electrodes. The nanoscale electrochemical data are used to model and predict multiscale electrochemical behavior, revealing that macroscopic cyclic voltammograms should be much more kinetically facile than observed experimentally. This indicates that parasitic resistances rather than redox kinetics play a dominant role in macroscopic measurements in these conductive polymer systems. SECCM further demonstrates that the ambient degradation of the P3HT electroactivity within P3HT/PMMA blends is spatially heterogeneous. This work serves as a roadmap for benchmarking the quality of conductive polymer films as electrodes, emphasizing the importance of nanoscale electrochemical measurements in understanding macroscopic properties.
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http://dx.doi.org/10.1021/acsnano.9b06302DOI Listing
November 2019

Effects of intubation with a double-lumen endotracheal tube on intraocular pressure during rapid sequence induction using succinylcholine chloride in patients with or without underlying systemic hypertension.

Anesth Pain Med (Seoul) 2019 Oct;14(4):449-455

Uijeongbu St. Mary's Hospital, The Catholic University of Korea, College of Medicine, Uijeongbu, Korea.

Background: Tracheal intubation is closely associated with increases in intraocular pressure (IOP); however, the effects of double-lumen tube (DLT) intubation on IOP have not been validated. Systemic hypertension (HTN) is another factor that may increase IOP. In this study, we observed differences in IOP increases between DLT and singlelumen tube (SLT) intubation, and evaluated the influence of underlying HTN during rapid sequence induction.

Methods: Sixty-eight patients were allocated into one of the following group: SLT/without HTN (n = 17), SLT/HTN (n = 17), DLT/without HTN (n = 17), and DLT/HTN (n = 17). An SLT was inserted for orthopedic or gynecological surgery, and a DLT was inserted for lung surgery after rapid sequence induction using succinylcholine. IOP was measured before anesthetic induction and until 10 min after intubation using a handheld tonometer (Tono-Pen AVIA).

Results: In the DLT/without HTN and DLT/HTN groups, the maximum increases in IOPs after tracheal intubation were 7.9 and 12.2 mmHg, respectively, compared to baseline. In the SLT/without HTN and SLT/HTN groups, the maximum increases were 5.0 and 4.9 mmHg, respectively, compared to baseline. In comparisons between patients with and without underlying HTN, the values of IOPs were comparable.

Conclusions: Tracheal intubation with a DLT is associated with more increases in IOPs than with an SLT in rapid sequence induction. Well-controlled underlying hypertension did not increase IOP during tracheal intubation.
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http://dx.doi.org/10.17085/apm.2019.14.4.449DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7713805PMC
October 2019

Amelioration of Mitochondrial Quality Control and Proteostasis by Natural Compounds in Parkinson's Disease Models.

Int J Mol Sci 2019 Oct 21;20(20). Epub 2019 Oct 21.

Division of Biotechnology, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea.

Parkinson's disease (PD) is a well-known age-related neurodegenerative disorder associated with longer lifespans and rapidly aging populations. The pathophysiological mechanism is a complex progress involving cellular damage such as mitochondrial dysfunction and protein homeostasis. Age-mediated degenerative neurological disorders can reduce the quality of life and also impose economic burdens. Currently, the common treatment is replacement with levodopa to address low dopamine levels; however, this does not halt the progression of PD and is associated with adverse effects, including dyskinesis. In addition, elderly patients can react negatively to treatment with synthetic neuroprotection agents. Recently, natural compounds such as phytochemicals with fewer side effects have been reported as candidate treatments of age-related neurodegenerative diseases. This review focuses on mitochondrial dysfunction, oxidative stress, hormesis, proteostasis, the ubiquitin‒proteasome system, and autophagy (mitophagy) to explain the neuroprotective effects of using natural products as a therapeutic strategy. We also summarize the efforts to use natural extracts to develop novel pharmacological candidates for treatment of age-related PD.
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http://dx.doi.org/10.3390/ijms20205208DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6829248PMC
October 2019

Progranulin attenuates liver fibrosis by downregulating the inflammatory response.

Cell Death Dis 2019 10 7;10(10):758. Epub 2019 Oct 7.

Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea.

Progranulin (PGRN) is a cysteine-rich secreted protein expressed in endothelial cells, immune cells, neurons, and adipocytes. It was first identified for its growth factor-like properties, being implicated in tissue remodeling, development, inflammation, and protein homeostasis. However, these findings are controversial, and the role of PGRN in liver disease remains unknown. In the current study, we examined the effect of PGRN in two different models of chronic liver disease, methionine-choline-deficient diet (MCD)-induced non-alcoholic steatohepatitis (NASH) and carbon tetrachloride (CCl4)-induced liver fibrosis. To induce long-term expression of PGRN, PGRN-expressing adenovirus was delivered via injection into the tibialis anterior. In the CCl4-induced fibrosis model, PGRN showed protective effects against hepatic injury, inflammation, and fibrosis via inhibition of nuclear transcription factor kappa B (NF-κB) phosphorylation. PGRN also decreased lipid accumulation and inhibited pro-inflammatory cytokine production and fibrosis in the MCD-induced NASH model. In vitro treatment of primary macrophages and Raw 264.7 cells with conditioned media from hepatocytes pre-treated with PGRN prior to stimulation with tumor necrosis factor (TNF)-α or palmitate decreased their expression of pro-inflammatory genes. Furthermore, PGRN suppressed inflammatory and fibrotic gene expression in a cell culture model of hepatocyte injury and primary stellate cell activation. These observations increase our understanding of the role of PGRN in liver injury and suggest PGRN delivery as a potential therapeutic strategy in chronic inflammatory liver disease.
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http://dx.doi.org/10.1038/s41419-019-1994-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6779917PMC
October 2019

The YAP1-NMU Axis Is Associated with Pancreatic Cancer Progression and Poor Outcome: Identification of a Novel Diagnostic Biomarker and Therapeutic Target.

Cancers (Basel) 2019 Sep 30;11(10). Epub 2019 Sep 30.

Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan 49315, Korea.

Yes-associated protein (YAP)-1 is highly upregulated in pancreatic cancer and associated with tumor progression. However, little is known about the role of YAP1 and related genes in pancreatic cancer. Here, we identified target genes regulated by YAP1 and explored their role in pancreatic cancer progression and the related clinical implications. Analysis of different pancreatic cancer databases showed that Neuromedin U (NMU) expression was positively correlated with YAP1 expression in the tumor group. The Cancer Genome Atlas data indicated that high YAP1 and NMU expression levels were associated with poor mean and overall survival. YAP1 overexpression induced NMU expression and transcription and promoted cell motility in vitro and tumor metastasis in vivo via upregulation of epithelial-mesenchymal transition (EMT), whereas specific inhibition of NMU in cells stably expressing YAP1 had the opposite effect in vitro and in vivo. To define this functional association, we identified a transcriptional enhanced associate domain (TEAD) binding site in the NMU promoter and demonstrated that YAP1-TEAD binding upstream of the NMU gene regulated its transcription. These results indicate that the identified positive correlation between YAP1 and NMU is a potential novel drug target and biomarker in metastatic pancreatic cancer.
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http://dx.doi.org/10.3390/cancers11101477DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6826421PMC
September 2019

A Hydroxypropyl Methylcellulose-Based Solid Dispersion of Curcumin with Enhanced Bioavailability and its Hepatoprotective Activity.

Biomolecules 2019 07 15;9(7). Epub 2019 Jul 15.

College of Korean Medicine, Gachon University, Seongnam 13120, Korea.

Curcumin is a polyphenol compound derived from the rhizomes of that exhibits antioxidant, anti-inflammatory, anticancer, and antimicrobial properties. However, its low solubility in aqueous solutions, low absorption following oral administration, and rapid degradation limit its use as a functional food material. In this study, a hydroxypropyl methylcellulose-based solid dispersion of curcumin (DW-CUR 20) was prepared and its bioavailability was evaluated. In addition, its therapeutic efficacy as a hepatoprotective agent was investigated using the model of tert-butyl hydroperoxide (t-BHP)-induced hepatocyte damage. The rat plasma pharmacokinetic study showed that the oral curcumin bioavailability of DW-CUR 20 significantly increased compared to that of non-formulated curcumin. DW-CUR 20 showed a concentration-dependent hepatocyte protective effect on t-BHP-induced HepG2 cells. DW-CUR 20 inhibited the release of lactate dehydrogenase and decreased apoptosis-related proteins such as Poly (ADP-ribose) polymerase, cleaved caspase-7 and cleaved caspase-8 on t-BHP-treated HepG2 cells. These findings suggest that DW-CUR 20 could be a promising formulation for enhancing the therapeutic efficiency of curcumin and for improving the safety.
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http://dx.doi.org/10.3390/biom9070281DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6681311PMC
July 2019

Highly Efficient (>10%) Flexible Organic Solar Cells on PEDOT-Free and ITO-Free Transparent Electrodes.

Adv Mater 2019 Sep 15;31(36):e1902447. Epub 2019 Jul 15.

School of Electrical Engineering (EE), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.

A novel approach to fabricate flexible organic solar cells is proposed without indium tin oxide (ITO) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) using junction-free metal nanonetworks (NNs) as transparent electrodes. The metal NNs are monolithically etched using nanoscale shadow masks, and they exhibit excellent optoelectronic performance. Furthermore, the optoelectrical properties of the NNs can be controlled by both the initial metal layer thickness and NN density. Hence, with an extremely thin silver layer, the appropriate density control of the networks can lead to high transmittance and low sheet resistance. Such NNs can be utilized for thin-film devices without planarization by conductive materials such as PEDOT:PSS. A highly efficient flexible organic solar cell with a power conversion efficiency (PCE) of 10.6% and high device yield (93.8%) is fabricated on PEDOT-free and ITO-free transparent electrodes. Furthermore, the flexible solar cell retains 94.3% of the initial PCE even after 3000 bending stress tests (strain: 3.13%).
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http://dx.doi.org/10.1002/adma.201902447DOI Listing
September 2019

Analysis and Identification of Active Compounds from Gami-Soyosan Toxic to MCF-7 Human Breast Adenocarcinoma Cells.

Biomolecules 2019 07 10;9(7). Epub 2019 Jul 10.

Department of Obstetrics and Gynecology, College of Korean Medicine, Daejeon University, Daejeon 35235, Korea.

Gami-soyosan is a medicinal herbal formulation prescribed for the treatment of menopausal symptoms, including hot flashes and osteoporosis. Gami-soyosan is also used to treat similar symptoms experienced by patients with breast cancer. The incidence of breast cancer in women receiving hormone replacement therapy is a big burden. However, little is known about the components and their mechanism of action that exhibit these beneficial effects of Gami-soyosan. The aim of this study was to simultaneously analyze compounds of Gami-soyosan, and determine their cytotoxic effects on estrogen receptor (ER)-positive MCF-7 human breast adenocarcinoma cells. We established a simultaneous analysis method of 18 compounds contained in Gami-soyosan and found that, among the various compounds in Gami-soyosan, gallic acid (), decursin (), and decursinol angelate () suppressed the viability of MCF-7 cells. Gallic acid (), decursin (), and decursinol angelate () induced apoptotic cell death and significantly increased poly (ADP-ribose) polymerase (PARP) cleavage and the Bcl-2-associated X protein/ B-cell lymphoma 2 (Bax/Bcl-2) ratio. Decursin () increased the expression of cleaved caspases-8, -9, -7, and -3. Decursinol angelate () increased the expression of cleaved caspase-8 and -7. These three components altered the different apoptosis signal pathways. Collectively, gallic acid (), decursin (), and decursinol angelate () may be used to inhibit cell proliferation synergistically in patients with ER-positive breast cancer.
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http://dx.doi.org/10.3390/biom9070272DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6681368PMC
July 2019

Synthesis of Single-Crystalline Hexagonal Graphene Quantum Dots from Solution Chemistry.

Nano Lett 2019 Aug 8;19(8):5437-5442. Epub 2019 Jul 8.

Department of Chemical and Biomolecular Engineering (BK21+ Graduate Program) , KAIST , Daejeon 34141 , South Korea.

Graphene-based carbon nanostructures with nanometer dimensions have been of great interest due to the existence of a bandgap. So far, well-ordered edge structure and uniformly synthesized graphene quantum dots (GQDs) with a hexagonal single-crystalline structure have not been directly observed owing to the limited precision of current synthesis approaches. Herein, we report on a novel approach not just for the synthesis of the size-controlled single-crystalline GQDs with hexagonal shape but also for a new discovery on constructing 2D and 3D graphene single crystal structures from d-glucose via catalytic solution chemistry. With size-controlled single-crystalline GQDs, we elucidated the crucial role of edge states on luminescence from the correlation between their crystalline size and exciton lifetime. Furthermore, blue-emissive single-crystalline GQDs were used as an emitter on light-emitting diodes and exhibit stable deep-blue emission regardless of the voltage and doping level.
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http://dx.doi.org/10.1021/acs.nanolett.9b01940DOI Listing
August 2019

Simple calculation of the optimal insertion depth of esophageal temperature probes in children.

J Clin Monit Comput 2020 Apr 29;34(2):353-359. Epub 2019 May 29.

Department of Anesthesiology and Pain Medicine, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, 93, Jungbu-daero, Paldal-gu, Suwon, Gyeonggi-do, 16247, Republic of Korea.

Placing an esophageal temperature probe (ETP) in the optimal esophageal site is important in various anesthetic and critical care settings to accurately monitor the core temperature of a pediatric patient. However, no reported study has provided a formula to calculate the optimal insertion depth of ETP placement in children based on direct measurement of the optimal depth. The aim of this study was to develop a simple and reliable method to determine the optimal depth of ETP placement in children via their mouth. Using preoperative chest computed tomography scans, intraoperative chest X-rays, and the actual depth of ETP insertion, we measured the optimal depth of ETP placement retrospectively in 181 children aged 3-13 years who underwent minimally invasive repairs of the pectus excavatum and removal of a pectus bar. A linear regression analysis was performed to assess the correlation of the optimal depth of ETP placement with the children's age, weight, and height. The optimal depth of ETP placement had a greater correlation with height than with age or weight, and the best-fit equation was '0.180 × height + 6.749 (cm) (R = 0.920).' We obtained three simplified formulae, which showed no statistically significant difference in predicting the optimal depth of ETP placement: height/6 + 8 (cm), height/5 + 4 (cm), and height/5 + 5 (cm). The optimal depth of ETP via children's mouths has a close correlation with height and can be calculated with a simple formula 'height/5 + 5 (cm)'.
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http://dx.doi.org/10.1007/s10877-019-00327-7DOI Listing
April 2020
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