• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.210-216
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• 2021

This study aimed to enhance ethanol productivity of Saccharomyces cerevisiae through genome editing using CRISPR/CAS9. To increase ethanol productivity, ACC1, ELO1, and OLE1 were overexpressed in S. cerevisiae using the CRISPR/CAS9 system. The strains overexpressing ACC1, ELO1, and OLE1 survived up to 24 h in YPD medium supplemented with 18% ethanol. Moreover, the ethanol yields in strains overexpressing ACC1 (428.18 mg ethanol/g glucose), ELO1 (416.15 mg ethanol/g glucose), and OLE1 (430.55 mg ethanol/g glucose) were higher than those in the control strains (400.26 mg ethanol/g glucose). In conclusion, the overexpression of these genes increased the viability of S. cerevisiae at high ethanol concentrations and the ethanol productivity without suppressing glucose consumption.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.51-58
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• 2008

Purpose: In dental clinical fields, various periodontal membranes are currently used for periodontal regeneration. The periodontal membranes are categorized into two basic types: resorbable and non-resorbable. According to the case, clinician select which membrane is used. Comparing different membranes that are generally used in clinic is meaningful. For this purpose, this study evaluates histological effects of various membranes in canine one wall intrabony defect models and it suggest a valuation basis about study model. Material and Method: The membranes were non-resorbable TefGen $Plus^{(R)}$, resorbable Gore Resolut $XT^{(R)}$ and resorbable $Osteoguide^{(R)}$. One wall intrabony defects were surgically created at the second and the mesial aspect of the fourth mandibular premolars in either right or left jaw quadrants in two dogs. The animals were euthanized 8 weeks post-surgery when block sections of the defect sites were collected and prepared for histological evaluation. Results: 1. While infiltration of inflammatory cells were observed in control, TefGen $Plus^{(R)}$ and Gore Resolut $XT^{(R)}$, it was not observed in $Osteoguide^{(R)}$. 2. TefGen $Plus^{(R)}$ had higher integrity than others and $Osteoguide^{(R)}$ was absorbed with folding shape. Gore Resolut $XT^{(R)}$ was divided everal parts during resorbtion and it was also absorbed from inside. 3. Quantity of new bone and new cementum was not abundant in all membranes. 4. For histologic evaluation of membranes we should consider infiltration of inflammatory, migration of junctional epithelium, integrity of membrane, quantity of new bone and new cementum, connective tissue formation and aspect of resorption. Conclusion: This histologic evaluation suggests that $Osteoguide^{(R)}$ provides periodontal regenerative environment with less inflammatory state. It is meangful that this study model suggests a valuation basis about other study model.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.184-190
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• 2007

Approximately 2.0 kb of the promoter region of the Pichia pastoris phosphoglycerate kinase gene (PGK1) was reduced to a 266 bp fragment and this minimized portion was used for construction of a new episomal constitutive expression vector in P. pastoris. As an approach to developing a constitutive expression vector in P. pastoris, the GAP promoter region of the Pichia expression vector pGAPZB was replaced with sequentially deleted PGK1 promoter fragments fused to a beta-galactosidase gene. When a lacZ gene was used as a reporter gene, PGK1 promoter strength was lower than that of the constitutive GAP promoter but it was higher than TEF1. We report here the development of the pPGKZ-E vector as a new episomal expression vector for heterologous gene expression by removing non-essential regions of the PGK1 promoter. This broadens the choice of episomal expression vectors for controlled constitutive expression in P. pastoris.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.297-312
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• 2020

Wilted soybean plants were collected from soybeans cultivation fields in Korea from 2014 to 2016. Fusarium spp., Colletotrichum spp., Rhizoctonia spp., Macrophomina sp., Phytophthora spp., and Calonectria ilicicola were obtained from the infected samples. Out of these, Fusarium spp. were the dominant species (79.1%). In total, 53 isolates were identified as F. solani species complex, F. oxysporum species complex, F. graminearum species complex, and F. fujikuroi species complex based on mycological characteristics. Sequence typing analysis was conducted using translation elongation factor 1 alpha (TEF) to confirm the identification of isolates. All isolates were identified as F. solani, F. oxysporum, F. commune, F. asiaticum, and F. fujikuroi based on phylogenetic analysis of TEF sequences. Pathogenicity of 44 isolates was tested on three cultivars of soybean using the root dip inoculation method. Out of 5 Fusarium species, only F. asiaticum could not cause the symptoms or be weak. Ten isolates were selected based on pathogenic characters and species identification to investigate the host range and screen soybean cultivars for resistance. Fusarium solani, F. oxysporum, and F. commune were aggressive only to soybean, and F. fujikuroi was aggressive to kidney bean, yellow cowpea, black cowpea, adzuki bean as well as soybean. All 13 Korean soybean cultivars were susceptible to F. commune and F. fujikuroi. Out of 13 cultivars, cv. Janggi, cv. Poongsannamul, and cv. Socheongja were resistant to Fusarium wilt, while cv. Hwanggeumol and Chamol were susceptible to Fusarium wilt.

• Animal Bioscience
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• v.36 no.1
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• pp.75-83
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• 2023

Objective: The objective of this study was to describe a methodological procedure to quantify the heat production (HP) partitioning in basal metabolism or fasting heat production (FHP), heat production due to physical activity (HPA), and the thermic effect of feeding (TEF) in roosters. Methods: Eighteen 54-wk-old Hy Line Brown roosters (2.916±0.15 kg) were allocated in an open-circuit chamber of respirometry for O₂ consumption (VO₂), CO₂ production (VCO₂), and physical activity (PA) measurements, under environmental comfort conditions, following the protocol: adaptation (3 d), ad libitum feeding (1 d), and fasting conditions (1 d). The Brouwer equation was used to calculate the HP from VO₂ and VCO₂. The plateau-FHP (parameter L) was estimated through the broken line model: HP = U×(R-t)×I+L; I = 1 if t<R or I = 0 if t>R; Where the broken-point (R) was assigned as the time (t) that defined the difference between a short and long fasting period, I is conditional, and U is the decreasing rate after the feed was withdrawn. The HP components description was characterized by three events: ad libitum feeding and short and long fasting periods. Linear regression was adjusted between physical activity (PA) and HP to determine the HPA and to estimate the standardized FHP (st-FHP) as the intercept of PA = 0. Results: The time when plateau-FHP was reached at 11.7 h after withdrawal feed, with a mean value of 386 kJ/kg^0.75/d, differing in 32 kJ from st-FHP (354 kJ/kg^0.75/d). The slope of HP per unit of PA was 4.52 kJ/mV. The total HP in roosters partitioned into the st-FHP, termal effect of feeding (TEF), and HPA was 56.6%, 25.7%, and 17.7%, respectively. Conclusion: The FHP represents the largest fraction of energy expenditure in roosters, followed by the TEF. Furthermore, the PA increased the variation of HP measurements.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.6
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• pp.453-460
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• 2022

Purpose: Esophageal atresia (EA) with or without tracheoesophageal fistula (TEF) is a congenital anomaly that can cause frequent digestive and nutritional problems, even after repair. The most common complication is anastomotic stricture, for which reoperation or balloon dilatation is performed. This study aimed to evaluate the postoperative complications of EA and the role of endoscopic balloon dilatation (EBD) in cases of anastomotic stricture. Methods: We retrospectively analyzed patients diagnosed with EA with or without TEF between January 2000 and February 2021. Patients' baseline characteristics, associated anomalies, and postoperative complications were reviewed. Results: Among 26 patients, 14 (53.8%) were male, 12 (46.2%) had coexisting anomalies, and the median follow-up was 6.1 years (range, 1.2-15.7 years). In univariate analysis, prematurity, low birth weight, and long-gap EA were associated with postoperative complications in 12 (46.2%) patients. Among the 10 (38.5%) patients with anastomotic stricture, nine (90.0%) required EBD. Regarding the first EBD, it was performed at a median of 3.3 months (range, 1.2-7.6 months) post-repair, while the average patient weight was 4.6 kg. The mean diameter ranged from 3.3 to 9.1 mm without major complications. In univariate analysis, long-gap EA alone was significantly associated with EBD. Conclusion: Approximately half of the patients experienced complications after EA repair. In particular, patients with a long-gap EA had a significantly increased risk of complications, such as anastomotic strictures. EBD can be safely used, even in infants.

• Advances in pediatric surgery
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• v.17 no.2
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• pp.154-161
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• 2011

Tracheoesophageal fistula without esophageal atresia (H-type TEF) is a congenital anomaly that is characterized by a fistula between the posterior wall of the trachea and the anterior wall of the esophagus, not accompanied by esophageal atresia. The purpose of this study is to investigate the clinical characteristics, diagnostic time, the side of cervical approach and short term result after surgery by searching medical records of patients treated for H-type TEF. The search was done at University of Ulsan, Department of Pediatric Surgery of Asan Medical Center, and the total number of patients from May 1989 to December 2010 was 9 with M:F ratio of 1:2. The median gestational age was $39^{+6}$ ($32^{+6}{\sim}41^{+0}$) wks. Seven out of nine patients were born at term and the other two were born premature. The clinical presentation was aspiration pneumonia, difficulty in feeding, chronic cough, vomiting, abdominal distension and growth retardation. The symptoms presented right after birth. The diagnosis was made with esophagography and the median time of diagnosis was 52 days of life. The majority of surgical corrections were performed within two weeks of diagnosis (median; 15d, range; 1d - 6m). Six patients had associated anomalies, and cardiac anomalies were most common. The cervical approach was utilized in all cases (right 2, left 7). Transient vocal cord palsy and minor esophageal leakage complicated two cases. Although the diagnosis of H-type TEF was difficult and often delayed, we had a good short term result. The left cervical approach was preferred.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.213-225
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• 2018

Trichoderma (Hypocreaceae) is one of the most ubiquitous genera worldwide. This genus has an excellent ability to adapt to diverse environments, even under poor nutritional conditions, such as in freshwater. However, little is known about the diversity of Trichoderma species in freshwater environments. In this study, we isolated diverse fungal strains from algae, plant litter, and soil sediment in streams in Korea. The strains were identified based on molecular phylogenetic analyses of internal transcribed spacer (ITS) rDNA and translation elongation factor 1 ($TEF1{\alpha}$) sequences. We also investigated their morphological characteristics by microscopic observation and determination of cultural features on different media. As a result, six Trichoderma species were found in Korea: T. afroharzianum, T. capillare, T. guizhouense, T. paraviridescens, T. reesei, and T. saturnisporum. Interestingly, T. paraviridescens showed both cellulose activity and hypoxia stress tolerance phenotypes, indicating its role as a decomposer in freshwater ecosystems. Our study revealed that freshwater environment could be a good candidate for investigating the species diversity of Trichoderma.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.106-114
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• 2024

Fusarium head blight (FHB), predominantly caused by Fusarium graminearum and F. asiaticum, is a significant fungal disease impacting small-grain cereals. The absence of highly resistant cultivars underscores the need for vigilant FHB surveillance to mitigate its detrimental effects. In 2023, a notable FHB outbreak occurred in the southern region of Korea. We assessed FHB disease severity by quantifying infected spikelets and grains. Isolating fungal pathogens from infected samples often encounters interference from various microorganisms. We developed a cost-effective, selective medium, named BGT (Burkholderia glumae Toxoflavin) medium, utilizing B. glumae, which is primarily known for causing bacterial panicle blight in rice. This medium exhibited selective growth properties, predominantly supporting Fusarium spp., while substantially inhibiting the growth of other fungi. Using the BGT medium, we isolated F. graminearum and F. asiaticum from infected wheat and barley samples across Korea. To further streamline the process, we used a direct PCR approach to amplify the translation elongation factor 1-α (TEF-1α) region without a separate genomic DNA extraction step. Phylogenetic analysis of the TEF-1α region revealed that the majority of the isolates were identified as F. asiaticum. Our results demonstrate that BGT medium is an effective tool for FHB diagnosis and Fusarium strain isolation.

• Clinical and Experimental Pediatrics
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• v.53 no.6
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• pp.705-710
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• 2010

Purpose: To determine the clinical manifestations and outcomes of patients with tracheoesophageal fistula (TEF) and esophageal atresia (EA) born at a single neonatal intensive care unit. Methods: A retrospective analysis was conducted for 97 patients with confirmed TEF and EA who were admitted to the neonatal intensive care unit between 1990 and 2007. Results: The rate of prenatal diagnosis was 12%. The average gestational age and birth weight were $37^{+2}$ weeks and $2.5{\pm}0.7kg$, respectively. Thirty-one infants were born prematurely (32%). Type C was the most common. The mean gap between the proximal and distal esophagus was 2 cm. Esophago-esophagostomy was performed in 72 patients at a mean age of 4 days after birth; gastrostomy or duodenostomy were performed in 8 patients. Forty patients exhibited vertebral, anorectal, cardiac, tracheoesophageal, renal, limb (VACTERL) association with at least 2 combined anomalies, and cardiac anomaly was the most common. The most common post-operative complications were esophageal stricture followed by gastroesophageal reflux. Balloon dilatation was performed for 1.3 times in 26 patients at a mean age of 3 months. The mortality and morbidity rates were 24% and 67%, respectively, and the most common cause of death was sepsis. The weight of approximately 40% patients was below the 10th percentile at 2 years of age. Conclusion: Mortality and morbidity rates of patients with TEF and EA are high as compared to those of infants with other neonatal surgical diseases. Further efforts must be taken to reduce mortality and morbidity and improve growth retardation.