• Proceedings of the Korean Society of Plant Pathology Conference
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• 1994.06a
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• pp.11-26
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• 1994

Crown gall of stonefruit and nut trees is one of the very few plant diseases subject to efficient biological control. The disease is caused by the soil-inhabiting bacteria Agrobacterium tumefaciens and Agrobacterium rhizogenes and the original control organism was a non-pathogenic isolate of A. rhizogenes strain K84. Control is achieved by dipping planting material in a cell suspension of strain K84 which specifically inhibits pathogenic strains containing a nopaline Ti plasmid. Because the agrocin 84-encoding plasmid (pAgK84) is conjugative, it can be transmitted from the control strain to pathogenic strains which, as a result, become immune to agrocin 84 and cannot be controlled. To prevent this happening, the transfer genes on pAgK84 were located and then largely eliminated by recombinant DNA technology. The resulting construct, strain K1026, is transfer deficient but controls crown gall just as effectively as does strain K84. Field data from Spain confirm that pAgK84 can transfer to pathogenic recipients from strain K84 but not from strain K1026. The latter has been registered in Australia as a pesticide and is the first genetically engineered organism in the world to be released fro commercial use. It is recommended as a replacement for strain K84 to prevent a breakdown in the effectiveness of biological control of crown gall. Several reports indicate that both strains K84 and K1026 sometimes control crown gall pathogens that are resistant to agrocin 84. A possible reason for this is that both strains produce a second antibiotic called 434 which inhibits growth of nearly all isolates of A. rhizogenes, both pathogens and non-pathogens. Crown gall of grapevine is caused by another species, Agrobacterium vitis. It is resistant to agrocin 84 and cannot be controlled by strains K84 or K1026. It is different from other crown gall pathogens in several characteristics, including the fact that, although a rhizosphere coloniser, its also lives systemically in the vascular tissue of grapevine. Pathogen free propagating material can be obtained from tissue culture or, less surely, by heat therapy of dormant cuttings. A number of laboratories are searching for a biocontrol strain that will prevent, or at least delay, reinfection. A non-pathogenic A. vitis strain F/25 from South Africa looks very promising in this regard.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.421-425
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• 2018

Methanol is a clear, colorless, volatile, and poisonous liquid that is commonly used as an industrial solvent. Visual impairment is a common symptom of methanol poisoning; however, visual impairment rarely occurs after exposure through inhalation. Therefore, visual loss after methanol intoxication via respiration has rarely been reported. We report a case of visual damage associated with methanol poisoning via respiratory exposure in an industrial setting. In this case in South Korea, a 28-year-old woman who worked at a cell phone factory was admitted to the emergency department with mental changes. She had blurred vision that began two days prior, but she did not come to the hospital until she experienced mental changes. She ranked 9 on the Glasgow Coma Scale and presented with severe metabolic acidosis. So, she was admitted to intensive care, and continuous renal replacement therapy was performed. Finally, she was discharged after recovery of her mental state, but had to undergo rehabilitation for six months. Also, her visual impairment was permanent. Methanol intoxication can occur through inhalation, which is difficult to detect initially. However, treatment of methanol poisoning is time-critical. Therefore, doctors should always keep in mind that methanol intoxication may occur via respiration. If in doubt, treatment should be given as soon as possible.

• Clinical and Experimental Pediatrics
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• v.50 no.1
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• pp.65-73
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• 2007

Purpose : Short stature is an important complication that impairs the quality of life in survivors of childhood brain tumors. We studied their final adult height (FAH) to evaluate risk factors for short stature. Methods : We reviewed the medical data of 95 survivors of childhood brain tumors (64 males and 31 females) who had been followed up from 1982 to 2006, reached FAH, and had a more than five year-disease-free survival. Results : Final adult height standard deviation score (FAHTSDS: $mean{\pm}SD$) of the patients was lower than those of general population ($-1.15{\pm}1.72$), HTSDS at diagnosis ($-0.13{\pm}1.57$), and target HTSDS ($-0.49{\pm}0.69$). FAHTSDS of craniopharyngioma patients did not decrease ($0.57{\pm}1.17$), but those of germ cell tumor and medulloblastoma patients were significantly reduced ($-1.20{\pm}1.45$, $-2.70{\pm}1.46$; P<0.05). The patients treated with craniospinal radiation or chemotherapy had lower FAHTSDS ($-1.93{\pm}1.58$, $-2.27{\pm}1.44$; P<0.01). In the spinal irradiation group, the younger the age at diagnosis was, the more the loss of FAH (r=0.442, P<0.01). Growth hormone replacement (GHR) didn't improve FAHTSDS, but starting GHR under 12 years was an independent factor for improving FAH once treatment methods were taken into account (P=0.01). Conclusion : The younger age at diagnosis, spinal radiation and chemotherapy were all important risk factors of height loss, and height gain was expected in patients who received GHR under the age of 12 years. Therefore, regular check-ups of growth and early intervention with growth hormones are needed for high risk groups to improve FAH.

• Journal of Chest Surgery
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• v.31 no.8
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• pp.739-748
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• 1998

Background: It has been well documented that transient occlusion of the coronary artery causes myocardial ischemia and finally cell death when ischemia is sustained for more than 20 minutes. Extensive studies have revealed that ischemic myocardium cannot recover without reperfusion by adequate restoration of blood flow, however, reperfusion can cause long-lasting cardiac dysfunction and aggravation of structural damage. The author therefore attempted to examine the effect of postischemic reperfusion on myocardial ultrastructure and to determine the rationales for recanalization therapy to salvage ischemic myocardium. Materials and methods: Young Holstein-Friesian cows(130∼140 Kg body weight; n=40) of both sexes, maintained with nutritionally balanced diet and under constant conditions, were used. The left anterior descending coronary artery(LAD) was occluded by ligation with 4-0 silk snare for 20 minutes and recanalized by release of the ligation under continuous intravenous drip anesthesia with sodium pentobarbital(0.15 mg/Kg/min). Drill biopsies of the risk area (antero-lateral wall) were performed at just on reperfusion(5 minutes), 1-, 2-, 3-, 6-, 12-hours after recanalization, and at 1-hour assist(only with mechanical respiration and fluid replacement) after 12-hour recanalization. The materials were subdivided into subepicardial and subendocardial tissues. Tissue samples were examined with a transmission electron microscope (Philips EM 300) at the accelerating voltage of 60 KeV. Results: After a 20-minute ligation of the LAD, myocytes showed slight to moderate degree of ultrastructural changes including subsarcolemmal bleb formation, loss of nuclear matrix, clumping of chromatin and margination, mitochondrial destruction, and contracture of sarcomeres. However, microvascular structures were relatively well preserved. After 1-hour reperfusion, nuclear and mitochondrial matrices reappeared and intravascular plugging by polymorphonuclear leukocytes or platelets was observed. However, nucleoli and intramitochondrial granules reappeared within 3 hours of reperfusion and a large number of myocytes were recovered progressively within 6 hours of reperfusion. Recovery was apparent in the subepicardial myocytes and there were no distinct changes in the ultrastructure except narrowed lumen of the microvessels in the later period of reperfusion. Conclusions: It is likely that the ischemic myocardium could not be salvaged without adequate restoration of coronary flow and that the microvasculature is more resistant to reversible period of ischemia than subendocardium and subepicardium. Therefore, thrombolysis and/or angioplasty may be a rational method of therapy for coronarogenic myocardial ischemia. However, it may take a relatively longer period of time to recover from ischemic insult and reperfusion injury should be considered.

• Journal of Chest Surgery
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• v.38 no.2 s.247
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• pp.157-163
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• 2005

Background: Clinical outcomes of esophageal cancer have not been satisfactory in spite of the development of surgical skills and protocols of adjuvant therapy. We analyzed the results of corrective surgical patients for esophageal cancer from January 1992 to July 2002. Material and Method: Among 129 patients with esophageal cancer, this study was performed in 68 patients who received corrective surgery. The ratio of sex was 59 : 9 (male : female) and mean age was $61.07\pm7.36$ years old. Chief complaints of this patients were dysphagia, epigastric pain and weight loss, etc. The locations of esophageal cancer were 4 in upper esophagus, 36 in middle, 20 in lower, 8 in esophagogastric junction. 60 patients had squamous cell cancer and 7 had adenocarcinoma, and 1 had malignant melanoma. Five patients had neoadjuvant chemotherapy. Result: The postoperative stage I, IIA, IIB, III, IV patients were 7, 25, 12, 17 and 7, respectively. The conduit for replacement of esophagus were stomach (62 patients) and colon (6 patients). The neck anastomosis was performed in 28 patients and intrathoracic anastomosis in 40 patients. The technique of anastomosis were hand sewing method (44 patients) and stapling method (24 patients). One of the early complications was anastomosis leakage (3 patients) which had only radiologic leakage that recovered spontaneously. The anastomosis technique had no correlation with postoperative leakage, which stapling method (2 patients) and hand sewing method (1 patient). There were 3 respiratory failures, 6 pneumonia, 1 fulminant hepatitis, 1 bleeding and 1 sepsis. The 2 early postoperative deaths were fulminant hepatitis and sepsis. Among 68 patients, 23 patients had postoperative adjuvant therapy and 55 paitents were followed up. The follow up period was $23.73\pm22.18$ months ($1\~76$ month). There were 5 patients in stage I, 21 in stage 2A, 9 in stage IIB, 15 in stage III and 5 in stage IV. The 1, 3, 5 year survival rates of the patients who could be followed up completely was $58.43\pm6.5\%,\;35.48\pm7.5\%\;and\;18.81\pm7.7\%$, respectively. Statistical analysis showed that long-term survival difference was associated with a stage, T stage, and N stage (p<0.05) but not associated with histology, sex, anastomosis location, tumor location, and pre and postoperative adjuvant therapy. Conclusion: The early diagnosis, aggressive operative resection, and adequate postoperative treatment may have contributed to the observed increase in survival for esophageal cancer patients.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.178-181
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• 2007

Purpose : The renal manifestations of tuberous sclerosis complex (TSC) are remarkably diverse, including polycystic kidney disease, simple renal cysts, renal cell carcinomas, and angiomyolipomas. All of these occur in children as well as adults in TSC. Angiomyolipomas, which can cause spontaneous life-threatening hemorrhages, are by far the most prevalent and the greatest source of morbidity. Here, we will address our experience, adding to the literature on pediatric patients with TSC requiring evaluation and treatment for renal manifestations. Methods : A retrospective analysis was made on 19 patients in whom TSC was diagnosed between May 2001 and Oct. 2005 at Severance Hospital. All patients had clinical diagnoses of TSC as defined by the 1998 tuberous sclerosis complex consensus conference. Results : The patients consisted of 13 boys and 6 girls with a mean age of 7.3 years (range 1 to 22). The renal disease associated with TSC included angiomyolipoma in nine patients (47.4 percent), renal simple cyst in one (5.3 percent), hydronephrosis in one (5.3 percent) patient. Eight patients (42.1 percent) presented with normal kidney contours at abdominal ultrasonography. One patient underwent renal replacement therapy due to chronic renal insufficiency after nephrectomy. Hemorrhage from angiomyolipoma was not detected. Conclusion : In our review of 19 cases of TSC, renal manifestations are reported in 57.9 percent of patients. Asymptomatic angiomyolipoma associated with TSC grow gradually, although severe hemorrhages are rare. So patients with TSC should be followed up with serial computerized tomography or abdominal ultrasonography. And also, renal function should be monitored conservatively.