• The Plant Pathology Journal
• /
• v.26 no.4
• /
• pp.409-416
• /
• 2010

Fusarium species, a large group of plant pathogens, potentially pose quarantine concerns worldwide. Here, we focus on the development of a method for detecting four Fusarium species in quarantined plants in Korea: F. solani f. sp. cucurbitae, F. stilboides, F. redolens, and F. semitectum var. majus. Species-specific primers were designed from the nucleotide sequences of either the translation elongation factor-1 alpha (TEF1) gene or RNA polymerase II subunit (RPB2) gene. Two different primer sets derived from TEF1, all specific to F. solani f. sp. cucurbitae, were able to differentiate the two races (1 and 2) of this species. A set of nested primers for each race was designed to confirm the PCR results. Similarly, two primer sets derived from RPB2 successfully amplified specific fragments from five F. stilboides isolates grouped within a single phylogenetic clade. A specific TEF1 primer set amplified a DNA fragment from only four of the 12 F. redolens strains examined, which were grouped within a single phylogenetic clade. All of the F. semitectum var. majus isolates could be specifically detected with a single RPB2 primer set. The specificity of the primer sets developed here was confirmed using a total of 130 Fusarium isolates.

• Journal of Chest Surgery
• /
• v.52 no.3
• /
• pp.170-173
• /
• 2019

A rare case of esophageal atresia/tracheo-esophageal fistula (EA-TEF) with an associated tracheobronchial remnant (TBR) is reported and discussed herein. A 13-month-old patient was seen with a complaint of vomiting of solid food 1 year after EA-TEF repair. An esophagogram showed a tapered narrowing in the lower segment of the esophagus. A re-operation was carried out and a pathologic examination of the resected stenotic segment revealed the presence of a TBR.

• Korean Journal of Bronchoesophagology
• /
• v.8 no.1
• /
• pp.61-65
• /
• 2002

Background : Acquired tracheoesophageal fistula(TEF) results mostly from Prolonged tracheal intubation and insertion of nasogastric tube. Although the incidence has decreased since the usage of low pressure, high volume cuff of endotracheal tube, it is seldom cured spontaneously and needs surgical treatment. Material and Methods : We have retrospectively reviewed five cases of TEF who underwent surgical treatment for cure from March, 1990 to September, 2001 and analyzed the cause, treatment, postoperative complications and prognostic factors. Results : Majority were men(80% : 4 of 5 patients) and the mean age was 29.4 years old(range, 11-58). The most predominant etiology was prolonged intubation or tracheostomy(80% : 4 of 5 patients) and 3 of 5 patients were treated by tracheal resection and end to end anastomosis with primary closure of esophagus. Postoperative complications occurred in 4 patients the most common complications were wound infection(4 cases) and esophageal leakage(2 cases). Extubation was done on postoperative day 11.5(range, 1-33) days, and factors causing delayed extubation were status esophagus. epilepticus, edema, and tracheal stenosis. Conclusion : Spontaneous closure of TEF is seldom possible and the surgical treatment of choice is tracheal resection and end to end anastomosis with primary repair of the esophagus. preoperative pulmonary rehabilitation and early extubation postoperatively are important factors for success.

• Advances in pediatric surgery
• /
• v.9 no.1
• /
• pp.6-11
• /
• 2003

This study reviews 14 years' experience treating esophageal atresia with special emphasis on the clinical profile and outcome. From May 1989 to February 2003, 65 cases of esophageal atresia (EA) were treated at Asan Medical Center. Boys outnumbered girls 2.4 to 1. Prematutity and low birth weight were 27.7% and 38.5%. Esophageal atresia with distal tracheoesophageal fistula (TEF) was the most common type (87.7%), followed by pure EA and H type fistula. Forty-six patients (70.8%) had one or more associated anomalies, cardiac malformations were the most common. Duodenal atresia was found in 7 cases. There were 6 patients (9.2 %) with VATER cluster. VACTERL cluster was present in 18 patients (27.7%), one of who fulfilled the complete syndrome. Waterston group A, B and C made up 21.5%, 40.0% and 38.5% of the total group. Surgical treatment was attempted in 63 patients and deferred in 2 who had severe associated malformations. For EA with distal TEF, primary esophago esophagostomy was carried out in 51 cases, and division of TEF and gastrostomy in 4 cases and no operation in 2 cases. For pure EA, colonic graft was done in 2 after gastrostomy and esophagostomy, and esophago esophagostomy was performed in 2 after gastrostomy. Two patients with pure EA are waiting for the second operation after gastrostomy. Division of TEF was carried out in 2 cases with H type TEF. The overall survival rate was 76.9%, and survival by Waterston classification was 100% in group A, 80.8% in B and 60.0% in C. Thorough workup for associated anomalies, interdepartmental approach and more careful surgical decision and technique are required to improve the outcome of EA.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.11
• /
• pp.1563-1570
• /
• 2010

To construct a highly sensitive detection system for endocrine disruptors (EDs), we have compared the activity of promoters with the n-alkane-inducible cytochrome P450 gene (ALK1), isocitrate lyase gene (ICL1), ribosomal protein S7 gene (RPS7), and the translation elongation factor-1${\alpha}$ gene (TEF1) for the heterologous gene in Yarrowia lipolytica. The promoters were introduced into the upstream of the lacZ or hERa reporter genes, respectively, and the activity was evaluated by ${\beta}$-galactosidase assay for lacZ and Western blot analysis for hER${\alpha}$. The expression analysis revealed that the ALK1 and ICL1 promoters were induced by n-decane and by EtOH, respectively. The constitutive promoter of RPS7 and TEF1 showed mostly a high level of expression in the presence of glucose and glycerol, respectively. In particular, the TEF1 promoter showed the highest ${\beta}$-galactosidase activity and a significant signal by Western blotting with the anti-estrogen receptor, compared with the other promoters. Moreover, the detection system was constructed with promoters linked to the upstream of the expression vector for the hER${\alpha}$ gene transformed into the Y. lipolytica with a chromosome-integrated lacZ reporter gene under the control of estrogen response elements (EREs). It was indicated that a combination of pTEF1p-hER${\alpha}$ and CXAU1-2XERE was the most effective system for the $E_2$-dependent induction of the ${\beta}$-galactosidase activity. This system showed the highest ${\beta}$-galactosidase activity at $10^{-6}\;M\;E_2$, and the activity could be detected at even the concentration of $10^{-10}\;M\;E_2$. As a result, we have constructed a strongly sensitive detection system with Y. lipolitica to evaluate recognized/suspected ED chemicals, such as natural/synthetic hormones, pesticides, and commercial chemicals. The results demonstrate the utility, sensitivity, and reproducibility of the system for identifying and characterizing environmental estrogens.

• Advances in pediatric surgery
• /
• v.14 no.1
• /
• pp.21-26
• /
• 2008

There is significant morbidity and mortality associated with the combination of esophageal atresia (EA) and duodenal atresia (DA). Nevertheless, the management protocol for the combined anomalies is not well defined. The aim of this study is to review our experience with the combined anomalies of EA and DA. From May 1989 to August 2006, seven neonates were diagnosed as EA with DA at Asan Medical Center. In all cases, the type of EA was proximal EA and distal tracheoesophageal fistula (TEF). The diagnosis of DA was made in theprenatal period in 1, at birth in 4, 4 days after birth in 1 (2 days after EA repair) and at postmortem autopsy in 1. Except the one case where DA was missed initially, primary simultaneous repair was attempted. DA repair with gastrostomy followed by EA repair in 2, EA repair followed by DA repair without gastrostomy in 2, and TEF ligation followed by DA repair with gastrostomy in 1. There were two deaths. One baby had a large posterolateral diaphragmatic hernia, and operative repair was not attempted. The other infant who had a TEF ligation and DA repair with gastrostomy expired from cardiac failure due to a large patent ductus arteriosus. Simultaneous repair of EA and DA appears to be an acceptable management approach for the combined anomalies, but more experience would be required for the selection of the primary repair of both anomalies.

• Analytical Science and Technology
• /
• v.23 no.6
• /
• pp.595-606
• /
• 2010

A total 221 samples of the retailed foods collected from 2004 to 2007 was examined to estimate the level of dioxins(29 congeners) by the isotopic dilution method, and the exposure of population of Korean to dietary of dioxins was performed. Dioxins levels were calculated using TEF values established in 1998 and 2005, respectively. The average levels (pg TEQ/g) were less than 0.01 for polished rice, 0.04 (poultry)-0.13 (beef) for meats, 0.04 (milk)-0.05(cheese) for milk and dairy products, 0.13 for egg (york, only) and 0.11 (alaska pollack)-1.35 (pacific mackerel) for fishes. The estimated daily intake of Korean through foods was 0.47 pg TEQ/kg bw/day, and it was estimated as about 11% to tolerable daily intake (TDI; 4 pg TEQ/kg bw/day) of Korea and Japan. Consequently, it was concluded that there was no health risk.

• The Korean Journal of Mycology
• /
• v.45 no.1
• /
• pp.74-82
• /
• 2017

Lisianthus (Eustoma grandiflorum) is a flowering ornamental plant used widely in Korea. In 2015, wilting, damping-off, stunting, and root rot symptoms were observed in lisianthus plants of Yeoju and Gimhae, Korea. Affected seedlings appeared yellow and showed poor development of root systems in the field and in nursery boxes. Furthermore, affected plants were yellow, stunted, and died at approximately 2-3 months after transplanting. Fusarium species were consistently isolated from the basal stems of diseased plants. Nine isolates were identified as Fusarium solani based on morphological characteristics. Macroconidia of isolates were relatively wide, straight-to-slightly curved, and microconidia formed in false heads on long monophialides. Abundant chlamydospores were produced at the middle or tips of hyphae. To confirm this identification, a molecular analysis of the translation elongation factor 1 alpha (TEF) and RNA polymerase II subunit (RPB2) genes was conducted. The sequences of TEF and RPB2 showed 99.2-99.9% and 98.0-98.1% similarity, respectively, to those of reference F. solani strains in NCBI GenBank. Pathogenicity was tested using root dipping inoculation of healthy lisianthus seedlings. Symptoms were observed within 7 days of inoculation only in inoculated plants. This is the first report of F. solani causing Fusarium root rot on lisianthus in Korea.

• The Korean Journal of Mycology
• /
• v.46 no.1
• /
• pp.58-68
• /
• 2018

Sunn hemp (Crotalaria juncea) is used as a nitrogen-fixing green manure in Korea to improve soil quality, reduce soil erosion, and suppress weeds and nematodes. In 2014, wilting sunn hemp plants were observed in green manure-cultivated fields in Wanju, Korea. Leaves of the infected plants began yellowing, starting with the lower leaves, eventually leading to their death. Moreover, a number of dark perithecia were observed on the wilting stems. Six isolates were obtained from these perithecia by single spore isolation. Based on their morphological characteristics, the isolates were identified as Fusarium udum (teleomorph: Gibberella indica). Macroconidia were slightly curved with almost hooked apical cell, and microconidia were formed on false heads by monophialides. Chlamydospores were produced abundantly in the hyphae, either singly or in clusters. To confirm the identification, multilocus sequence analysis was conducted using translation elongation factor 1 alpha (TEF), calmodulin (CAL), and histone 3 (HIS3). The sequences of TEF, CAL, and HIS3 showed 94.4~96.2%, 99.7%, and 99.6~99.8% similarity to the reference sequences of F. udum in NCBI GenBank, respectively. Pathogenicity was tested on sunn hemp and two soybean cultivars using the inoculation method of soil drenching with spore suspension. The wilting symptoms were observed only in sunn hemp and one cultivar of soybean (cv. Teagwang) after 14~21 days of inoculation. This is the first report of wilt disease in sunn hemp caused by Fusarium udum in Korea.

• Mycobiology
• /
• v.47 no.1
• /
• pp.76-86
• /
• 2019

Scab disease caused by Venturia nashicola is of agroeconomic importance in cultivation of Asian pear. However, little is known about the degree of genetic diversity in the populations of this pathogen. In this study, we collected 55 isolates from pear scab lesions in 13 major cultivation areas in Korea and examined the diversity using sequences of internal transcribed spacer (ITS) region, ${\beta}$-tubulin (TUB2), and translation elongation factor-$1{\alpha}$ ($TEF-1{\alpha}$) genes as molecular markers. Despite a low level of overall sequence variation, we found three distinctive subgroups from phylogenetic analysis of combined ITS, TUB2, and $TEF-1{\alpha}$ sequences. Among the three subgroups, subgroup 1 (60% of isolates collected) was predominant compared to subgroup 2 (23.6%) or subgroup 3 (16.4%) and was distributed throughout Korea. To understand the genetic diversity among the subgroups, RAPD analysis was performed. The isolates yielded highly diverse amplicon patterns and none of the defined subgroups within the dendrogram were supported by bootstrap values greater than 30%. Moreover, there is no significant correlation between the geographical distribution and the subgroups defined by molecular phylogeny. Our data suggest a low level of genetic diversification among the populations of V. nashicola in Korea.