• Animal cells and systems
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• v.7 no.3
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• pp.261-264
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• 2003

Leiden), no mutation was detected in either group. Allele frequencies of A2379G and G2391 A mutations were not significantly different between CAD patients and controls. Non-Caucasian populations have a considerably lower factor Ⅴ Leiden allele frequency than Caucasian populations. Thus, it may be due to differences in the genetic background as well as environmental factors.

• YAKHAK HOEJI
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• v.58 no.1
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• pp.7-11
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• 2014

To study the resistance mechanism of E. faecalis to LCB01-0371, several resistant mutants to LCB01-0371 or linezolid were isolated by step-wise selection. The frequency of spontaneous mutations resistant to LCB01-0371 was lower than that of linezolid in E. faecalis. The genetic variations in resistant mutants were analyzed by DNA sequencing of domain V of 23S rRNA in each mutant. The first-step mutant to LCB01-0371 had a G2576T point mutation in V domain of 23S rRNA. However, no resistant mutant to LCB01-0371 was isolated in second-step mutant selection.

• Journal of Plant Biology
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• v.36 no.1
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• pp.105-112
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• 1993

Selection of glyphosate-resistant clones from MNNG-treated mesophyll protoplasts of haploid tobacco and their differentiation were studied. The protoplasts were treated with 0.1 to 100 $\mu\textrm{g}$/mL N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) for 30 min when they expanded to oval shapes. After the treatment, the protoplasts in 4-16 cell stages were transferred to the selective medium containing 1 mM glyphosate for the selection of the glyphosate-resistant colonies. The efficiency of the cell division of the protoplasts in the selective medium decreased as the MNNG concentrations in creased. Optimal MNNG concentration for induction of the glyphosate-resistant clones was 10$\mu\textrm{g}$/mL and mutation frequency was 2.66$\times$10-6. The stability of the glypohsate-resistance of the clones was examined by prolonged subculture in the medium with 1 mM glyphosate, and the resistant clones were survived more than 10 months. Among them one clone has been proliferating and greening and the others were proliferating without greening or greening with slower proliferating.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.453-465
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• 2000

Background : Lung carcinogenesis is a multistage process involving alterations in multiple genes and diverse pathway. Mutational activation of oncogenes and inactivation of tumor suppressor genes, and subsequent increased genetic instability are the major genetic events. The p53 gene and FHIT gene as tumor suppressor genes contribute to the pathogenesis of lung cancer, evidenced by mutation, microsatellite instability(MI) and loss of heterozygosity(LOH). Methods : We analysed genetic mutations of p53 and FHIT gene in 29 surgical specimens of nonsmall cell lung cancer using PCR-single strand conformation polymorphism, DNA sequencing and RT-PCR. MI and LOH were analyzed in loci of D3S1285, D9S171, and TP53. Results : In 2 cases, point mutation of p53 gene was observed on exon 5. MI of 3 times and LOH of 14 times were observed in at least one locus. In terms of the location of microsatellite, D3S1285 as a marker of FH1T was observed in 5 cases out of 26 specimens; D9S171 as a marker of p16 in 5 out of 17; and TP53 as a marker of p53 in 7 out of 27. In view of histologic type, squamous cell carcinoma presented higher frequency of microsatellite alteration, compared to others. Mutation of FHIT gene was observed in 11 cases and 6 cases of those were point mutation as a silent substitution on exon 8. FHIT mRNA expression exhibited deletion on exon 6 to 9 in 4 cases among 15 specimens, presenting beta-actin normally. Conclusion : Our results show comparable frequency of genetic alteration in nonsmall cell lung cancer to previous studies of Western countries. Microsatellite analysis might have a role as a tumor marker especially in squamous cell carcinoma. Understanding molecular abnormalities involved in the pathogenesis could potentially lead to prevention, earlier diagnosis and the development of novel investigational approaches to the treatment of lung cancer.

• Journal of Life Science
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• v.19 no.5
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• pp.664-670
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• 2009

The ${\beta}$3-adrenergic receptor (ADRB3) is expressed mainly in visceral adipose tissue and is thought to contribute to lipolysis and the delivery of free fatty acids to the portal vein. This study was aimed at evaluating the association between high-density lipoprotein cholesterol (HDL-C) and ADRB3 genetic polymophisms. A total of 991 healthy examinees who were examined in a university hospital, located in Busan City, between May and December 2006 were enrolled in this study. Height, weight, body mass index, waist circumference, and systolic and diastolic blood pressures of the subjects were examined. Intravenous concentrations of fasting blood glucose, total cholesterol, HDL-C, low-density lipoprotein cholesterol, and triglyceride were also measured. After extracting DNA from the subjects, mutations of the +188T>C (Trp64Arg) of exon 1 and +3893T>C of intron 2 on the ADRB3 gene were genotyped using the single base extension method. We have identified a novel mutation of ADRB3 that is located in intron 2. The frequency of its minor allele was 0.164. Both the +188T>C mutation of exon 1 and +3893T>C mutation of intron 2 were significantly associated with HDL-C. The mean concentration of serum HDL-C was significantly lower in the presence of their minor allele 'C'. These results suggest that both mutations of +188T>C of exon 1 and +3895T>C of intron 2 have significant associations with HDL-C in the Korean population.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.41-47
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• 1999

To investigate the combined effect of gamma ray irradiation and NaCl treatment on Tradescantia somatic cell pink mutations, potted plants of Tradescantia 4430 were evenly sprayed with NaCl solution(170mM) 24 hours before irradiation(NaCl+${\gamma}$) and after irradiation(${\gamma}$+NaCl). Irradiation doses were 0.3, 0.5, 1.0 and 2.0 Gy of gamma-ray. The plants irradiated only with gamma radiation were used as control group(CT). Frequency of pink mutation increased linearly with irradiation close and the peak interval of elevated mutation frequencies appeared during 6∼12 days aver irradiation in all the experimental groups. The slope of dose-response curve in CT was 5.99($r^2$=0.99), while it were 4.55($r^2$=0.98) in NaCl+${\gamma}$ and 4.33($r^2$=0.99) in ${\gamma}$+NaCl. It seemed that pre- and post-treatment of NaCl had a protective effect it against radiation-induced cell damages since it decreased the slope value by more than 24%. It is suggested that protective effect on DNA damages can be invoked in irradiated stamen hair cells by NaCl treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.539-543
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• 2016

Background: It is well known that peritoneal carcinomatosis (PC) from colorectal cancer (CRC) is associated with a poor prognosis. However, data on the prognostic significance of modern chemotherapy containing bevacizumab, cetuximab or panitumumab are not available. Materials and Methods: This retrospective review concerned 526 patients with metastatic CRC who were classified into two groups according to the presence or absence of PC, and were treated with systemic chemotherapy, with or without bevacizumab or anti-EGFR antibodies. The genetic background, in particular KRAS, BRAF, and PIK3CA gene mutations, and overall survival (OS) were compared between the two groups. Results: The median OS values were 23.3 and 29.1 months for PC and non-PC patients, respectively (hazard ratio [HR]=1.20; p=0.17). Among all patients, tumor location, number of metastatic sites and BRAF mutation status were significant prognostic factors, whereas the presence of PC was not. In the PC group, chemotherapy with bevacizumab resulted in a significantly longer OS than forchemotherapy without bevacizumab (HR=0.38, p<0.01), but this was not the case in the non-PC group (HR=0.80, p=0.10). Furthermore, the incidence of the BRAF V600E mutation was significantly higher in PC than in non-PC patients (27.7% versus 7.3%, p<0.01). BRAF mutations displayed a strong correlation with shorter OS in non-PC (HR=2.26), but not PC patients (HR=1.04). Conclusions: Systemic chemotherapy, especially when combined with bevacizumab, improved survival in patients with PC from CRC as well as non-PC patients. While BRAF mutation demonstrated a high frequency in PC patients, but it was not associated with prognosis.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.321-326
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• 2014

Background: Mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC) are predictive of response to EGFR-targeted therapy in advanced stages of disease. This study aimed to determine the frequency of EGFR mutations in NSCLCs and to correlate their presence with clinical characteristics in multiethnic Malaysian patients. Materials and Methods: In this prospective study, EGFR mutations in exons 18, 19, 20 and 21 in formalin-fixed paraffin-embedded biopsy specimens of consecutive NSCLC patients were asessed by real-time polymerase chain reaction. Results: EGFR mutations were detected in NSCLCs from 55 (36.4%) of a total of 151 patients, being significantly more common in females (62.5%) than in males (17.2%) [odds ratio (OR), 8.00; 95% confidence interval (CI), 3.77-16.98; p<0.001] and in never smokers (62.5%) than in ever smokers (12.7%) (OR, 11.50; 95%CI, 5.08-26.03; p<0.001). Mutations were more common in adenocarcinoma (39.4%) compared to non-adenocarcinoma NSCLCs (15.8%) (p=0.072). The mutation rates in patients of different ethnicities were not significantly different (p=0.08). Never smoking status was the only clinical feature that independently predicted the presence of EGFR mutations (adjusted OR, 5.94; 95%CI, 1.94-18.17; p=0.002). Conclusions: In Malaysian patients with NSCLC, the EGFR mutation rate was similar to that in other Asian populations. EGFR mutations were significantly more common in female patients and in never smokers. Never smoking status was the only independent predictor for the presence of EGFR mutations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.348-353
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• 1996

Mutation tachniques inducing more useful mutations and reducing somatic effects need to be improved for crop breeding. Seeds of barley varieties ; Dema, Grosso were treated with two types of mutagens ; 1) chemical treatment: single treatment or double treatment of two mutagens (N-nitroso-N-methylurea ; MNH, Sodium Azide; NaN$_3$) 2) gamma ray irradiation treatment. After treatment, half of seeds were used for germination test and half of seeds were sown to the field. With the higher dose of mutagen both chemical and gamma ray were plants treated, the higher rate of growth reduction rate was in M$_1$ seedling. In chemical treatment, germination rate of seeds, growth rate of coleoptile and root in double treatment of chemical mutagens were better than single treatments, especially in same dose. Growth inhibition rate of plant in double treatment of 1.0mM MNH(0.5mM MNH + 0.5mM MNH), for example, were less than one of plants of single treatment of 1.0mM MNH in pot and petri dish test. Growth reduction rate of culm and fertility rate in M$_1$ plants double treated in same dose of single treatment were also less than single one. With the higher dose of mutagen both chemical and gamma ray were plants treated, the higher frequency of chlorophyll mutants was in M$_2$ seedling. The rate of chlorophyll mutants in double treatment of chemical mutagens were higher than single treatment. Double treatment methods can be a improved method for induction of new good mutants, which were induced more useful mutations and reduced harmful somatic effects.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.21-26
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• 1999

To investigate the combined effect of radiation and pesticide on Tradescantia somatic cell mutations, potted plants of Tradescantia 4430 on which parathion had been sprayed evenly 24 hours before irradiation. Radiation doses were 0.3, 0.5, 1.0 and 2.0 Gy of gamma-ray. The plants irradiated only with the gamma-ray radiation were used as control groups (CT). Pink mutation frequency increased linearly proportional to the radiation dose and the peak interval of elevated mutation frequencies appeared during 7 ~ 11 days after irradiation in both CT and Pa +${\gamma}$ groups. The slope of dose -response curve in CT was 5.99 ($r^2$= 0.988), while it was 3.43 (r$x^-2$=0.981) in Pa+${\gamma}$. It seemed that parathion pretreatment had a protective effect against radiation-induced cell damages since it decreased the slope value by 43%. It is suggested that an adaptive response or radiomodification could be induced in irradiated stamen hair cells by parathion pretreatment.