• Development and Reproduction
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• v.13 no.2
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• pp.115-122
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• 2009

Spermatogenesis and ultrastructural characteristics of sperm of brackish water diploid Corbicula japonica were investigated by electron microscope observations. Based on the cytological studies, the spermatozoon of this species (brackish water diploid) C japonica is approximately 55 ${\mu}m$ in length. The sperm head (about 12 ${\mu}m$ long) is elongated and tapers with a slight curve. Sperm nucleus is about 7.90 ${\mu}m$ long, and the acrosome is about 2.70 ${\mu}m$ long: The morphologies of the sperm nucleus type and the acrosome shape of this species are a long arrow-like type and long cone-like shape, respectively. The sperm head of this species (external fertilization, dioecious and oviparous species) is partially modified from that of the primitive type, as seen in triploid Corbicula species (internal fertilization, hermaphrodite and ovoviparous species), reported by some authors. However, this species produces uniflagellate spermatozoa, unlike freshwater triploid hermaphroditic clams being possessed of partially modified biflagellate spermatozoa. Diploid C japonica is similar to those of other bivalves being possessed of a short midpiece containing four mitochondria surrounding the centrioles. The axoneme of the sperm tail flagellum consists of nine pairs of microtubules at the periphery and a pair at the center. The axoneme of the sperm tail shows a 9+2 structure, and from uniflagellate sperm cross sectioned, in particular, wing-like axonernal lateral fins are observed, as seen in external fertilization fishes.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.317-323
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• 2016

An isoflavone glucosidase that catalyzes the hydrolysis of isoflavone glucosides into glucose and corresponding aglycones was purified from Candida fermentati SI. The N-terminal sequence was determined to be GLNCDYCN. We designed degenerate primers on the basis of these amino acid sequences and successfully cloned the full structural gene sequence of the isoflavone glucosidase using inverse PCR. The exo-β-(1,3)-glucanase gene consists of 1227 base-pair nucleotides, encoding a 408-amino-acid sequence that shares 41–96% amino acid homology with other yeast exo-β-(1,3)-glucanases belonging to glycoside hydrolase family 5. The recombinant exo-β-(1,3)-glucanase was expressed in Pichia pastoris X-33, using a pPICZA vector system, and further characterized. The molecular mass of the purified exo-β-(1,3)-glucanase was estimated by SDS-PAGE to be 47 kDa. The optimal pH and temperature were pH 4.5 and 40℃, respectively. The K_m values of the purified exo-β-(1,3)-glucanase for daidzin and genistin were 0.12 mM and 0.14 mM, respectively. The V_max values of the purified isoflavone glucosidase were 945.03 U/mg for daidzin and 835.92 U/mg and for genistin.

• The Korean Journal of Physiology
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• v.14 no.1
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• pp.1-5
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• 1980

This study was under taken to investigate the influences of predictable or unpredictable stress upon gastric ulceration, and the hippocampectomy upon the ulceration order the stressful conditions. Sixty male albino rats(Sprague-Dawley strain) were divided equally into 3 groups: One was the hippocampal group(N=20) which received hippocampal ablation by suction, another was the cortical control group(N =20) which received partial cortical ablation over the hippocampus, and a third was the normal control group(N=20). Each group was further divided into two subgroups: One was the predicted subgroup(N=10) in which animals could predict the imminent stressful stimuli by hearing a sound(1,000 Hz, 2 sec in duration) 3 sec before the onset of the stress, and the other was the unpredicted subgroup(N=10). After starvation for 24 hours, but water ad libitum, each rat received the electric stimulation(3 mA, 60 Hz, 2 sec in duration, and once per minute in average) for 6 hours via a pair of electrodes attached on the tale. The electric stimulation served as the stress causing the gastric ulcer. Five hours after completion of stimulation, the stomach filled with the physiological saline was removed under deep anesthesia and spread out on a small glass plate. The numbers of the ulcer in each stomach were counted and the shape was examined under the dissecting microscope. Results obtained were as follows: 1. The mean numbers of the ulcer of the predicted subgroups were significantly larger than those of the unpredicted subgroups in the normal control and the cortical control groups, but there was no difference between the values of the two subgroups in the hippocampal group. 2. The mean numbers of the ulcer of the predicted subgroups in the normal control and the cortical control groups were larger(but not significant) than that in the hippocampal group. It is inferred from the above results that the prediction of the stress strengthens the effect of the stress on the gastric ulceration, and the hippocampus facilitates the effect of the prediction of the stress.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.335-338
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• 2005

For the development of qualitative PCR detection method of genetically modified rice (Oryza sativa L.), rice species specific gene, SAMDC1 (S-adenosylmethionine decarboxylase), was selected and validated as suitable for use as an endogenous reference gene in rice. The primer pair OsSAMDC1-5'/3' with 110 bp amplicon was used for amplification of the rice endogenous gene, SAMDC1 and no amplified product was observed from 19 different plants as templates. Qualitative PCR method was assayed with 2 different GM rices (Milyang 204 and Iksan 483) developed in Korea. For the qualitative PCRs, the construct-specific detection primer pairs were constructed. Os204-5'/OsNOS-3' amplifying the junction region of GUS gene and NOS terminator introduced in Milyang 204 gave rise to an amplicon 172 bp; also, Os483-5'/OsNOS-3' amplifying the junction region of Bar gene and NOS terminator introduced in Iksan 483 gave rise to an amplicon 161 bp.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.199-205
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• 2017

Although many PCR-based assays have been developed, the majority of rapid detection of Toxoplasma gondii in animal and their meat product has been dependent on immunogenic assays. Thus, there is still a need for more reliable PCR based detection method for T. gondii in retail meats. Recently, a 529-bp repeat element that exists in 200-300 copies per genome of T. gondii genome had been spotlighted for its usefulness as potential detection targers. In this study, the 529-bp repeat element was selected for real-time PCR to detect three types of T. gondii (type I, II and III). A primer pair targeting 82-bp of the 529-bp element detected all three types of T. gondii and showed high level of specificity against 14 different food-borne pathogens as well as 3 protozoan parasites such as Giardia lamblia, Cryptosporidium parvum and Entamoeba histolytica. Application of the new real-time PCR assay in meat samples showed improved detection sensitivity compared to the B1-gene targeted method suggesting potential new target for Toxoplasma gondii screening in retail meats.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.1
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• pp.45-53
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• 1995

Working depth of the model net was determined by using of the same experimental tank and the same model net that used in the forwarded report in a series studies. The depth of the net which indicates the depth of the head rope from the water surface, was determined by the photographs taken in front of the net mouth with the combination of towing velocity, warp length and distance between paired boats. The results obtained can be summarized as follows: 1. Working depth of model nets A and B was varied in the range of 0.09~1.66$m$,and 0.04~1.34$m$(which can be converted into 2.7~40.2$m$and 1.2~49.8$m$in the full-scale net) respectively, and the depth of model net A was slightly deeper than the depth of the model net B. 2. Working depth ($D$,which is appendixed m for the model net, f for the full-scale net, A and B for the types of the model nets) can be expressed as the function of towing velocity$V_t$, as in the model net($V_t$=$m$/$sec$) $D_{mA}$=(-1.99+0.65$L_w$) $e^{-1.72V_t}$ $D_{mA]$=(-1.91+1.04 $L_w$) $e^{2.88V_t}$ in the full-scale net($V_t$=$k$'$t$ $D_{fA}$=(-29.32+0.65$L_w$)$e^{0.40 V_t}$ $D_{fB}$=(-57.60+1.04$L_w$)$e^{-0.67 V_t}$ 3. Working depth 9$D$ appendixes are as same as the former) can be expressed as the function of warp length$L_w$) in the model net, and can be converted into full-scale net as in the model net ($V_t$=$m$/$sec$) $D_{mA}$=-0.99 $e^{-1.42V_t}$+0.67$e^{-1359V_t}$$L_w$ $D_{mB}$=-.258$e^{-3.77V_t}$+1.16$e^{-3.15V_t$ $L^w$, in the full-scale net($V_t$=k't) $D_{fA}$=-29.28$e^{-0.32V_t}$+0.67$e^{-0.37V_t$$L_w$ $D_{fB}$=-69.10$e^{-0.81V_t}$+1.16$e^{-0.72V_t}$$L_w$. 4. Working depth was gradually shallowed according to the increase of the distance between paired boats.

• The Journal of the Korean life insurance medical association
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• v.2 no.1
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• pp.152-181
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• 1985

A statistical analysis on the cardiothoracic ratio in insurance medicine was carried out for 5,200 insured persons who were medically examined including photofluorography of the chest at the Honam medical department, Dong Bang life insurance Company, Ltd from November, 1979 to August, 1984. The results were as follows: 1. The mean value of the cardiothoracic ratio in all of the insured was $44.2{\pm}4.3%$. The mean value of the cardiothoracic ratio was $43.1{\pm}4.1%$ in all males and $45.2{\pm}4.2%$ in all females, and the difference of the values between males and females showed statistical significance(P<0.001). In each age group, the mean value of the cardiothoracic ratios of female was higher than that of male without exception and the difference of the values between males and females showed statistical significance(P<0.001). The mean value of the cardiothoracic ratio showed gradual increase with age from the second to sixth decade in male(P<0.05 or 0.001 after fourth decade) and from the second to seventh decade in female(P<0.05 or 0.001 from the second to sixth decade). 2. Correlation between both sexes and among age groups relating to the cardiothoracic ratios of the insureds seen to be a physiological phenomenon of the cardiac size and should be considered on the rating of the cardiothoracic ratio. Based on the correlation above mentioned and an author's assumption that the incidence of normal and abnormal cardiothoracic ratios in each age group would show the same rate in male and female, author prepared a modified rating table from the existing table; in male group the existing rating table is used and in female group the ratings of 0, 30-50, 50-100 and 100-D are to calculate by the cardiothoracic ratio of 51%or under, 52-56%, 57-61% and 62% or over respectively in the age group below 39, by the cardiothoracic ratio of 52% or under, 53-57%, 58%-62% and 63% or over respectively in the age group of 40-49, by the cardiothoracic ratio of 53% or under, 54-58%, 59-63% and 64% or over respectively in the age group over 60. 3. The relative frequency distribution polygons of the cardiothoracic ratio of both sexes drawn in a pair on one coordinate plane revealed lying in juxtaposition each other horizontally and showed the shifting of females polygon to male's one toward the direction of greater value of the cardiothoracic ratio at a short distance which increased gradually with age. 4. The minimum cardiothoracic ratio was 31.2% and the maximum cardiothoracic ratio was 63.6% in all of the insured. 5. In each age group, no significant sex difference was found in the relative frequency distribution of ratings by the cardiothoracic ratios of 5,200 insureds by using the rating table modified by author, while significant sex difference was found by using the existing rating table.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1075-1083
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• 2015

Adipose tissue deposited within muscle fibers, known as intramuscular fat (IMF or marbling), is a major determinant of meat quality and thereby affects its economic value. The biological mechanisms that determine IMF content are therefore of interest. In this study, 48 genes involved in the bovine peroxisome proliferator-activated receptor signaling pathway, which is involved in lipid metabolism, were investigated to identify candidate genes associated with IMF in the longissimus dorsi of Hanwoo (Korean cattle). Ten genes, retinoid X receptor alpha, peroxisome proliferator-activated receptor gamma (PPARG), phospholipid transfer protein, stearoyl-CoA desaturase, nuclear receptor subfamily 1 group H member 3, fatty acid binding protein 3 (FABP3), carnitine palmitoyltransferase II, acyl-Coenzyme A dehydrogenase long chain (ACADL), acyl-Coenzyme A oxidase 2 branched chain, and fatty acid binding protein 4, showed significant effects with regard to IMF and were differentially expressed between the low- and high-marbled groups (p<0.05). Analysis of the gene co-expression network based on Pearson's correlation coefficients identified 10 up-regulated genes in the high-marbled group that formed a major cluster. Among these genes, the PPARG-FABP4 gene pair exhibited the strongest correlation in the network. Glycerol kinase was found to play a role in mediating activation of the differentially expressed genes. We categorized the 10 significantly differentially expressed genes into the corresponding downstream pathways and investigated the direct interactive relationships among these genes. We suggest that fatty acid oxidation is the major downstream pathway affecting IMF content. The PPARG/RXRA complex triggers activation of target genes involved in fatty acid oxidation resulting in increased triglyceride formation by ATP production. Our findings highlight candidate genes associated with the IMF content of the loin muscle of Korean cattle and provide insight into the biological mechanisms that determine adipose deposition within muscle.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1537-1544
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• 2015

Meat and carcass quality attributes are of crucial importance influencing consumer preference and profitability in the pork industry. A set of 400 Berkshire pigs were collected from Dasan breeding farm, Namwon, Chonbuk province, Korea that were born between 2012 and 2013. To perform genome wide association studies (GWAS), eleven meat and carcass quality traits were considered, including carcass weight, backfat thickness, pH value after 24 hours (pH24), Commission Internationale de l'Eclairage lightness in meat color (CIE L), redness in meat color (CIE a), yellowness in meat color (CIE b), filtering, drip loss, heat loss, shear force and marbling score. All of the 400 animals were genotyped with the Porcine 62K SNP BeadChips (Illumina Inc., USA). A SAS general linear model procedure (SAS version 9.2) was used to pre-adjust the animal phenotypes before GWAS with sire and sex effects as fixed effects and slaughter age as a covariate. After fitting the fixed and covariate factors in the model, the residuals of the phenotype regressed on additive effects of each single nucleotide polymorphism (SNP) under a linear regression model (PLINK version 1.07). The significant SNPs after permutation testing at a chromosome-wise level were subjected to stepwise regression analysis to determine the best set of SNP markers. A total of 55 significant (p<0.05) SNPs or quantitative trait loci (QTL) were detected on various chromosomes. The QTLs explained from 5.06% to 8.28% of the total phenotypic variation of the traits. Some QTLs with pleiotropic effect were also identified. A pair of significant QTL for pH24 was also found to affect both CIE L and drip loss percentage. The significant QTL after characterization of the functional candidate genes on the QTL or around the QTL region may be effectively and efficiently used in marker assisted selection to achieve enhanced genetic improvement of the trait considered.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.6
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• pp.640-647
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• 2006

It is difficult to treat wastewater involved in heavy metal in electroplating industry. Recently, many industries adopt the clean technology to prevent production of pollutant in the process or reuse after the appropriate pollutant treatment. In this study, we estimate the ability of recovery of nickel and the efficiency using lab-scale ion exchange and electrodialysis process with electroplating industry wastewater. In the ion exchange experiments with 5 types of resin, the result showed that S 1467(gel-type strong acidic cation exchange resin) has the highest exchange capacity. And it showed that the 4 N HCl has the highest in regeneration efficiency and maximum concentration in the regeneration experiments with various kinds md concentration of the regenerant. During the electrodialysis experiments, we varied the current density, the concentration of electrode rinse solution, the flow rate of concentrate and electrode rinse solution in order to find the optimum operating condition. As a result, we obtained $250A/m^2$ of current density, 2 N $H_2SO_4$ of concentration of electrode rinse solution, 30 mL/min of flow rate of concentrate and electrode rinse solution as the best operating conditions. We performed the scale-up experiments on the basis of ion exchange and electrodialysis experiments. And we obtained the experimental result that exchange capacity of S 1467 was 1.88 eq/L resin, and regeneration efficiency was 93.7% in the ion exchange scale-up experiment, we also got the result that concentration and dilution efficiency increased, and current efficiency kept constant in the scale-up experiments.