• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.269-276
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• 2008

Field resistance is defined as the resistance that allows effective control of a parasite under natural field condition and is durable when exposed to new races of that parasite. To identify the genes for field resistance to rice blast, quantitative trait loci (QTLs) conferring the resistance for races and blast nursery screening in japonica rice cultivars were detected and mapped using SSR markers. QTL analysis was carried out in 190 RILs population from the cross between Suweon365 (moderately resistant) and Chucheong (highly susceptible). Twelve QTLs against nine blast races inoculated were detected on chromosomes 1, 2, 4, 6, 7, 11 and 12. They explained from 5.1% to 34.9% of total phenotypic variation. Eight QTLs against blast nursery screening in four regions for three years were detected on chromosomes 1, 2, 4, 11 and 12. The phenotypic variation explained by each QTL ranged from 4.3% to 37.7%. Three chromosome segment substitution lines (CSSLs) of $BC_2F_6$ by backcross method were developed to transfer the QTLs into the susceptible cultivar Chucheong as a recurrent parent. A CSSL4-1 containing two QTLs qLB6.2 and qLB7 against blast races showed to the reaction of 6 to 7 at blast nursery in two regions for two years. The CSSL4-2 and CSSL93 containing QTLs, qLB11.2 and qLB12.1 of the resistance against leaf blast in blast nursery screening, respectively, had enhanced the resistance for blast nursery screening across two regions and in two years.

• Archives of Pharmacal Research
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• v.19 no.4
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• pp.251-257
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• 1996

The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is subject of great concern at present. In this respect, the genetic toxicity of fenpropathrin ((RS)-.alpha.-cyano-3-phenoxybenzyl-2,2,3,3-tetramethyl cyclopropane carboxylate, CAS No.:39514-41-8), a pyrethroid insecticide, was evaluated in bacterial gene mutation system, chromosome aberration in mammalian cell system and in vivo micronucleus assay with rodents. In bacterial gene mutation assay, no mutagenicity of fenpropathrin (62-$5000\mug/plate$) was observed in Salmonella typhimurium TA 98, 100, 1535 and 1537 both in the absence and in the presence of S-9 metabolic activaton system. In mammalian cell system using chinese hamster lung fibroblast, no clastogenicity of fenpropathrin was also observed both in the absence and in the presence of metabolic activation system in the concentration range of $7-28\mug/ml$. And also, in vivo micronucleus assay using mouse bone marrow cells, fenpropathrin also revealed no mutagenic potential in the dose range of 27-105 mg/kg body weight of fenpropathrin (i.p.). Consequently, no mutagenic potential of fenpropathrin was observed in vitro bacterial, mammalian mutagenicity systems and in vivo micronucleus assay in the dose ranges used in this experiment.

• Journal of Aquaculture
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• v.21 no.4
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• pp.259-264
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• 2008

Cytogenetic characteristics of three Hemibarbus species (H. labeo, H. longirostris and H. mylodon) were analyzed based on erythrocyte measurement, flow cytometric estimation of cellular DNA content, and karyological analysis. Average nuclear volumes for H. labeo, H. longirostris and H. mylodon were 22.5, 21.7 and $26.0\;{\mu}m^3$, respectively. The estimated genome sizes of those three species were not significantly different from one another, being recorded as 2.51, 2.33 and 2.35 pg/cell for H. labeo, H. longirostris and H. mylodon, respectively. Modal chromosome numbers of the three species were the same as 2n = 50. However, their karyotypes and fundamental numbers (FN) were different among species; 16M+16SM+18T/A (FN = 82) for H. labeo, 18M+16SM+16T/A (FN = 84) for H. longirostris and 18M+24SM+8T/A (FN = 92) for H. mylodon.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1103-1108
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• 2008

An investigation to determine frequency and distribution of folate sensitive chromosomal fragile sites was carried out in a Pakistani breed of Lohi sheep to uncover fragile site phenomena. The means and standard errors of aberrant cell count (AC) and Number of aberrations (NoA) in Lohi sheep were $0.56{\pm}0.15$ and $0.59{\pm}0.16$ in the control cultures. FUdR treated cells showed significantly higher (p<0.001) AC and NoA means ($2.18{\pm}0.33$ and $2.65{\pm}0.50$). The sex comparison for the frequency of expression indicated that males had significantly higher number of aberrant cells and total number of aberrations in FUdR cultures than the female group in Lohi sheep. The comparison of control cultures was however, not significantly different between the two groups. The regression analysis of FUdR-induced chromosomal fragility data analysis of the fragility data predicted very low ${\beta}$ of 0.325 and 0.412 for AC and NoA respectively. Lohi chromosomes expressed lesions in only 7 and 24 bands in the control and FUdR cultures respectively. The total number of significantly fragile bands in the Lohi genome was only 4. The X-chromosome of the Lohi sheep was highly stable at $5{\mu}g/ml$ FUdR with no fragile sites. The sex comparison for the distribution of fragile sites across the Lohi genome did not reveal any noticeable differences.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.3 no.2
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• pp.75-79
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• 2007

Background: Down's syndrome, or trisomy 21, is the commonest congenital chromosome anomaly. With improvement in medical care, these patients increasingly reach adulthood in spite of their physical maldevelopment and mental retardation. And, the number of those who required general anesthesia for dental treatment is increasing. Methods: We reviewed the 26 cases of 22 patients with Down's syndrome who underwent outpatient general anesthesia for dental treatment at the clinic for the disabled in Seoul National University Dental Hospital. Results: The mean age was 22 years. They all had severe mental retardation and some had congenital heart anomaly, epilepsy, hypothyroidism, acute leukemia, autism, cleft palate, and chronic renal failure. For anesthesia induction, 4 cases was needed physical restriction, but others showed good or moderate cooperation. Drugs used for anesthesia induction was thiopental (17 cases) and sevoflurane (9 cases). All patients received nasotracheal intubation and 3 cases needed difficult airway management. Mean total anesthetic time was $166{\pm}60$ min and staying time at PACU was $92{\pm}48$ min. There was no death or long term hospitalization because of severe complications. Conclusion: If general anesthesia is needed, pertinent diagnostic tests and workup about anomaly, and appropriate anesthetic planning are essential for safety.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8197-8201
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• 2014

Background: Telomerase reverse transcriptase (TERT) and cleft lip and palate trans-membrane 1 like (CLPTM1L) genes located on chromosome 5p15.33 are known to influence the susceptibility to various cancers. Here, we examined the association of TERT and CLPTM1L single nucleotide polymorphisms (SNPs) with hepatocellular carcinoma (HCC). Materials and Methods: Genotyping of TERT SNP rs2736098 and CLPTM1L SNP rs401681 was performed using TaqMan allelic discrimination assays in a case-control study of 201 HCC cases and 210 controls in a Chinese male population. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression analyses. Results: Both the rs2736098 T allele of TERT and the rs401681 T allele of CLPTM1L were associated with a significantly increased risk of HCC (adjusted odds ratio [OR]=1.605, 95% confidence interval [CI]=1.164-2.213; adjusted OR=1.399, 95%CI=1.002-1.955, respectively). Individuals carrying both TERT and CLPTM1L risk genotypes had an even higher risk of HCC (adjusted OR=4.420, 95%CI= 2.319-8.425). The TERT rs2736098 T allele was also significantly associated with the level of the HCC clinical indicator alpha-fetoprotein (P=0.026). Conclusions: Our results show that genetic variants of TERT and CLPTM1L may contribute to HCC susceptibility in Chinese males.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1061-1065
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• 2017

Objective: This study was conducted to locate quantitative trait loci (QTL) influencing fatty acid (FA) composition in a large $F_2$ intercross between Landrace and Korean native pigs. Methods: Eighteen FA composition traits were measured in more than 960 $F_2$ progeny. All experimental animals were genotyped with 165 microsatellite markers located throughout the pig autosomes. Results: We detected 112 QTLs for the FA composition; Forty seven QTLs reached the genome-wide significant threshold. In particular, we identified a cluster of highly significant QTLs for FA composition on SSC12. QTL for polyunsaturated fatty acid on pig chromosome 12 (F-value = 97.2 under additive and dominance model, nominal p-value $3.6{\times}10^{-39}$) accounted for 16.9% of phenotypic variance. In addition, four more QTLs for C18:1, C18:2, C20:4, and monounsaturated fatty acids on the similar position explained more than 10% of phenotypic variance. Conclusion: Our findings of a major QTL for FA composition presented here could provide helpful information to locate causative variants to improve meat quality traits in pigs.

• Environmental Mutagens and Carcinogens
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• v.21 no.1
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• pp.14-22
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• 2001

The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. In this respect, administrative authorities has great concern to regulate and to evaluate the chemical hazard to environment and human health. The clastogenicity of 28 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. Glycidylacrylate which is one of the most cytotoxic chemical among 28 chemicals tested revealed clastogenicity in the range of 0.31-1.25 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system. Neopentyl glycol (340-1360 $\mu\textrm{g}$/$m\ell$) also revealed weak positive result both in the presence and absence of metabolic activation system. Cyanoguanidine (/$420.5-841 $\mu\textrm{g}$m\ell$) and N-butylchloride ($231.5-926 $\mu\textrm{g}$/m\ell$) revealed weak positive result only in the absence of S-9 metabolic activation system. Nevertheless total aberration percentages of N-butylchloride in the presence of metabolic activation system, and 3,4＇-dichlorobenztrifluoride in the absence of S-9 metabolic activation revealed above 5% aberration, there is no statistical significance. From the results of chromosomal aberration assay with 28 synthetic chemicals in Chinese hamster lung cells, glycidylacrylate (CAS No. 106-90-0), neopentyl glycol (CAS No. 126-30-7), N-butyl chloride (CAS No. 109-69-3) and cyanoguanidine (CAS No. 461-58-5) revealed positive clastogenic results in this study.

• Journal of Aquaculture
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• v.3 no.2
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• pp.135-144
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• 1990

Fertilized eggs of Oreochromis niloticus were subjected to cold treatments at $14^{\circ}C$ for 30, 45 and 60 minutes starting 5 minutes after insemination at $27^{\circ}C$. Ploidy levels were determined by chromosome preparations and the analysis of both cell and nuclear sizes. A temperature shock of $14^{\circ}C$ for 60 minutes yielded the best results ( $83.3\%$). Gonadal development in both sexes was severely retarded in all triploid groups at 6 months of age.

• Journal of Life Science
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• v.20 no.12
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• pp.1902-1905
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• 2010

This study was conducted to increase the efficiency of farming practice in rainbow trout, Oncorhynchus mykiss, by sex reversal and chromosome-set manipulation techniques. Induction of sex-reversed gynogenetic diploid rainbow trout males and mass production of all-female rainbow trout by genetic sex reversal was performed. Phenotypic males in the gynogenetic diploid group were induced successfully by dietary administration of 5 mg of 17 alpha-methyltestosterone per kg diet for 82 days. All females were produced by crossing between normal female and sex-reversed gynogenetic diploid male rainbow trout.