• Journal of Plant Biotechnology
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• v.47 no.2
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• pp.164-171
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• 2020

Transgenic Alstroemeria plants resistant to Alstroemeria mosaic virus (AlMV) were generated through RNA-mediated resistance. To this end, the friable embryogenic callus (FEC) of Alstroemeria was induced from the leaf axil tissue and transformed with a DNA fragment containing the coat protein gene and 3'-nontranslated region of AlMV through an improved particle bombardment system. The bar gene was used as a selection marker. More than 300 independent transgenic FEC lines were obtained. Among these, 155 lines resistant to phosphinothricin (PPT) were selected under low stringent conditions. After increasing the stringency of PPT selection, 44 transgenic lines remained, and 710 somatic embryos from these lines germinated and developed into shoots. These transgenic shoots were then transferred to the greenhouse and challenged with AlMV. In total, 25 of the 44 lines showed some degree of resistance. PCR analysis confirmed the presence of the viral sequence. Virus resistance was observed at various levels. Establishment of an efficient transformation system for Alstroemeria will allow inserting transgenes into this plant to confer resistance to viral and fungal pathogens. Accordingly, this is the first report on the production of a transgenic virus-resistant Alstroemeria and lays the foundation for alternative management of viral diseases in this plant.

• Journal of Ginseng Research
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• v.11 no.1
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• pp.56-65
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• 1987

Grown-gall tumor was induced from the infection of Panax ginseng C.A. Meyer by Agrobacterium tumefaciens C58 and the tumor calli were formed on the phytohormone free MS medium. The calli were friable and rough in appearance. Calli obtained from crown gall tumor were similar to and indistinguishable from each other. The tumor callus was quite different from normal callus. Tumor callus grew rapidly, whereas mal callus appeared late. The growth of tumor callus was better in the dark than in the light. In suspension culture, the fresh weight of tumor callus was twice as much in comparison with normal callus.

• Korean Journal of Veterinary Research
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• v.48 no.2
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• pp.197-201
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• 2008

Plasmodium spp. in domestic and wild birds are microscopic, intracellular parasitic protozoa within the blood cells and tissues cause avian malaria. A 17-month-old Magellan penguin (Spheniscus magellanicus) with a clinical signs of anorexia, depression, and respiratory distress for 3 days was submitted to the Pathology Department of Veterinary Medicine, Cheju National University in October 2005. It was born and reared in the Jeju Island. Grossly, the liver was enlarged, pale and friable. The spleen was also enlarged with dark red coloration and friable. Histopathologically, the lesions in the liver were characterized by multifocal infiltration of macrophages and lymphocytes especially in perivascular regions. The schizonts of Plasmodium spp. contained up to 30 merozoites were found in numerous infiltrated mononuclear cells. Similarly, histiocytic cells were proliferated in red pulp of spleen and the schizonts were found in these cells. Numerous dark brown pigments were widely distributed in the liver and spleen. The result of the nested polymerase chain reaction clarified the causative agent of this case was Plasmodium spp.. This is the first report for the outbreak of avian malaria caused by Plasmodium spp. in a penguin that was born and reared in Jeju Island in Korea.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.176.2-176
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• 2003

• Journal of Plant Biology
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• v.29 no.1
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• pp.11-18
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• 1986

Protopasts were isolated from cultured cells of potato (Solanum tuberosum L.) tuber tissue. The ability of callus formation from the culture cells was higher in cultivars Dejima and Superior than in Shimabara and Irish Cobbler on Lam's medium. Therefore, the former was used as sources for protoplast isolation. Friable calli were transferred to liquid media and cells in exponential phase were used for protoplast isolation. In both of Dejima and Superior, the yield of protoplasts was high in the enzyme solution of 2% Onozuka cellulase and 1% macerozyme. Also, viability of isolated protoplasts was very good. Thus, it seems that these protoplasts would be applicable to various aims of research.

• Journal of Plant Biotechnology
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• v.30 no.2
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• pp.115-121
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• 2003

In this study, plant regeneration and Agrobacterium tumefaciens-mediated transformation Kentucky bluegrass(Poa pratensis L.) were evaluated. Three different types of calli were produced depending on the combinations of growth regulators. They were non-friable brown or gray-colored callus (type I), compact, friable and yellow or white-colored callus (typeII), and soft, watery translucent callus with differentiated structure (typeIII). The highest regenerable organogenic callus (typeII) was obtained on the medium containing 1mg/L, 2,4-D and 0.1mg/L BA. Additionally, the production of typeII calli increased significantly when AgNO$_3$ was added to the callus induction and growth medium. The highest frequency of multiple shout formation from typeII callus was obtained on MS medium containing 1mg/L BA and 1mg/L Thidiazuron(TDZ). The organogenic calli(typeII) were inoculated with Agrobacterium tumefaciens strain EHA101 harboring the binary vector pIG121Hm with $\beta$-glucuronidase gene, and various factors were found to influence the transfer-DNA delivery efficiency. The highest transient GUS activity was observed on typeIIcallus. In the present work, we reported the first transient GUS activity of Kentucky bluegrass mediated by Agrobacterium tumefaciens. Our system may contribute to genetic improvement for breed-recalcirtrant grass species, Kentucky bluegrass.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.3
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• pp.124-128
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• 1989

This experiment was conducted to determine factors affecting callus induction of Vernal alfalfa. Growth regulators, basal medium, medium pH, explant age, and agar concentration for callus induction were investigated. The results obtained were as follows: For the callus induction, 2-5 mg/l 2,4-D alone was found to be most effective on callus induction. Cytokinins did not have positive effect on the callus induction, and even the more cytokinin added induced the less callus. Callus yield was much higher in B5 or SH medium than in any other media. The calli induced in PC and MS media were more friable than those induced in other media. The medium pH of 5.8 gave the best response of callus induction. At higher than pH 7.0, callus induction was inhibited severely. The effective seedling age for callus induction was around 9 days. In agar concentration, 0.5 % (W/V) was suitable for callus induction and it was severely depressed at above 1 %. Callus induction was not influenced by day length or illumination. Calli cultured under 1618 hour lightldark cycle became more compact and green than those cultured under the dark.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.2
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• pp.165-175
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• 1996

Fourteen(14) large commercial buildings located in Seoul with friable sprayed-on surface insulation material on ceiling were investigated for fiber types in bulk material and for airborne fiber concentrations in buildings by transmission electron microscopy (TEM) in order to compare the results with those by polarized light microscopy (PLM) and phase contrast microscopy (PCM). The results were as follows: 1. Chrysotile asbestos was found in one bulk sample out of total 14 bulk samples collected. Glass fiber and mineral wool were the two major constituents of the bulk samples. 2. The Na-Mg-Si-Ca-Fe-Al ratios of the EDX spectra which were normalized with the Si peak were 0-1.0-10-8.3-4.0-4.0 in mineral wool and 0-5-10-21-0-0 in chrysotile asbestos, respectively. 3. Airborne fiber concentrations were log-normalcy distributed and the geometric mean (geometric standard deviation) fiber concentrations by TEM in the underground parking lots and inside buildings were 0.0048 f/cc(1.93) and 0.0040 f/cc(2.27), respectively with no statistical difference. In the outdoor ambient air, statistically significantly lower concentration of 0.0018 f/cc(2.04) was measured. 4. The TEM/PCM ratios of airborne fiber concentrations ranged 0.5 - 2.0 for 80 % of airborne samples analyzed, end the regression equation between TEM and PCM was PCM=-0.2724+1.1355(TEM) with the coefficient of determination $R^2=0.52$. The results of this study confirmed that the sprayed-on surface insulation material found in some commercial buildings may possibly be contaminated with asbestos fiber. Since statistically significant relationship of fiber concentrations measured by PCM and TEM inside buildings and ambient air was found, previous results by PCM in ambient air could be used to estimate the ambient fiber concentrations in knowing the ratio of TEM/PCM.

• Journal of Chest Surgery
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• v.13 no.3
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• pp.250-255
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• 1980

Myxoma is a benign growth constituting nearly 50% of all primary cardiac tumors. It is important because it can be abolished by surgical therapy and is usually fatal if unrecognized and untreated. Recently a wider use of echocardiogram as the screening test of valve lesions can be expected to increase the number of myxomas found preoperatively. We report a case of left atrial myxoma which was diagnosed by echocardiogram before surgery, and was successfully removed with the aid of extracorporeal circulation. The patient was a 24-year old woman who had suffered from mitral valvular symptoms for 2 months before admission. At operation, a tumor, measuring 5.2 x 4.3 x 4.7 cm, was extremely friable, villous gelatinous mass and it was removed from its origin near the closed fossa ovalis, including its stalk and a portion of the septum. The postoperative course was uneventful. The patient is clinically well and without symptoms of heart disease.

• The Journal of the Korean dental association
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• v.14 no.11
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• pp.906-908
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• 1976

A case of pyogenic granuloma between left central lncisor and upper left lateral lncisor was observed in an 18year old Korean male. the characteristics were as follow 1) The side of the cuccerence was betweeb gum of the upper left central lncisor and that of the lateral lncisor. 2) It is bright red or purple red anf either friable or firm depending upon its duration in the majority of cases it presents surface ulceration and purulent exudation 3)Granuloma pyogenicum is similar in clinical and microscopic appearance to the conditioned gingival enlargement seen in pregnancy. Differencial diagnosis depends upon the patient's history.