• Applied Microscopy
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• v.31 no.4
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• pp.355-365
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• 2001

This study was performed to investigate the distribution and differentiation on the immunoreacted cells of the ChAT (choline acetyltransferase) at the Meynert basal nucleus of the forebrains in the growth periods of rat, using the immunohistochemistric method. According to the cell shape and the ratio of long axis vs short axis of cell soma, the ChAT antibody reacted nerve cells in the Meynert basal nucleus of the rats were classified into six types. In the adult rats, the FD (frequency distributions) of round, oval and elongated cells were maximum. The FD of these types were shown to be progressively decreased during the postnatal development. In addition, the FD of elongated nerve cells in were observed in the adult rats respectively. This was thought to be the same phenomenon as those in the round and oval cells . The total mean volume of ChAT antibody reacted cell somata was lowest in the PND (postnatal days) 7 rats and was highest in the PND 21 rats. But, those were decreased to the adult. These results suggest that ChAT antibody reacted nerve cells grow up to PND 21 and then, differentiate into the various types by neurites outgrowing. On the electron micrography, the adult rat forebrain cells were obtained to be well developed ribosomes, polysomes , rough endoplasmic reticula and mitochondria. The immunreactivities were observed in ribosomes, polysomes, rough endoplasmic reticula and outer membrane of mitochondria. Golgi complexes were poorly developed and not showed jmmunreactivity. The ribosomes , polysomes and endoplasmic reticula are considered to be closely related to the inter cellular localization and biosynthesis of the ChAT but not Golgi complex. According to the results in the present study, it is considered that the ChAT-immunoreacted nerve cells in the Meynert basal nucleus of the rat forebrains are differentiated throughout the postnatal development with following processes of changes; 1) the cholinergic nerve cells develop postnatally 2) cell soma volumes gradually increase during the early postnatal days 3) and then, cells differentiate into the various types by projecting the neurites to the appropriate area after PND 21.

• Journal of Yeungnam Medical Science
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• v.14 no.2
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• pp.383-392
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• 1997

To study the differences of bone mineral density according to the gestational ages and the birth weight and get a reference data for the diagnosis of metabolic bone diseases in the newborn infants, bone mineral densities of the lumbar vertebrae were measured in fifty-three newborn infants born at Yeungnam University Hospital from March 1, 1995 to February 28, 1997, whore gestational ages were between $28^{+3}$ and $41^{+3}$ weeks and who had no intrauterine growth retardation, using dual energy X-ray absorptiometry (X-R 26, Norland, USA) within seven days of life. 1. There was no sexual difference in bone mineral density. The bone density increased significantly as gestational age increased from $0.149{\pm}0.009g/cm^2$ at 28-30wks to $0.229{\pm}0.034g/cm^2$ at 39-41wks of gestational age (p<0.05), but there was no significant difference between bone mineral densities at 33-34 wks and 35-36wks. There was positive linear correlation between gestational age and bone mineral density ($Y=7.5{\times}10^{-3}X-0.082$, r=0.7018, p<0.001). 2. The bone mineral density increased significantly as the birth weight increased from $0.158{\pm}0.020g/cm^2$ in 1,000-1,499 g to $0.251{\pm}0.021g/cm^2$ in 3,500-4,000 g of the birth weight (p<0.05), but there was no significant difference between bone mineral densities in 1,000-1,499 g and 1,500-1,999 g of the birth weight. There was positive linear correlation between the birth weight and the bone mineral density ($Y=3.9{\times}10^{-5}X+0.093$, r=0.7296, p<0.001). There were positive correlations between the bone mineral density and gestational age, and between the bone mineral density and the birth weight. It can be used as a reference data for the further study on the bone mineral metabolism in the newborn infants including preterm babies.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.187-194
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• 1995

The male broiler chichens (Hibreed Ross P. S 120 birds) were experimented for 6 weeks in cage. while experimental diets were feded to addition 0, 0, 0. 2, 0. 5 and 1.0% levels with Root Powder of Bupleurum Falcatum Linne (RPBFL). The results were as following; The tast of RPBFL added diets was favorite as the feed intake of RPBFL diets were increased than control diet. Body weight gain (1. 845g) in 1. 0% RPBFL diet was higher enhenced by 226g/per bird than control (1. 619g). was effected above 14%. Feed re­quierment was the lowest by 2. 02 in control, and was significantly enhenced to 1. 81 in 1. 0% RPBFL diet (P<0. 01). The amounts of carcass ratio were significantly defferent effected from the broilers feding diet added with 1. 0% RPBFL (P<0. 01). Greater amounts of chest meat was produced by 253g from the broilers fed diet added 1. 0% RPBFL, was enhenced 42g than the control broilers. The chest meat vs live body weight ratio was increaced in 1. 0% added diet. According to the tendency be increased' of the RPBFL levels, the drumst­ick weight was enhenced with 1. 0% RPBFL diet. The ratio of the drumstick vs live body weight was im­proved in 1. 0% RPBFL diet. The weights of liver. spleen, heart and gizzard were heavied according to live body weight, then was improved in 1. 0% RPBFL diet. Fat accumulation (abdominal and gizzard sur­rounding) was greater abserved by 50. 12g from the broiler fed ration with 1. 0% RPBFL. Content of total serum protein was high concetration in control, then was decrased by RPBFL level. Total serum cholesterol and triglyceride contents were increased in proportion to fat accumulation ratio.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.193-197
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• 2014

Transgenic crops that produce insecticidal toxins have a great potential for controlling target pest insects, but there is a growing concern about unintended influences on non-target species. In the present study, the preferences and performance of non-target green peach aphid, Myzus persicae (Sulzer), on transgenic cabbages (Brassica oleracea) that produce Bt toxin (Cry1Ac1) and untransformed control plants were investigated as a part of risk assessment. In a free-choice situation, the number of nymphs larviposited by 10 winged adults over 3 days was $21.9{\pm}1.8$ and $22.5{\pm}2.2$ on transgenic and the control plants, respectively, indicating that the aphids did not discriminate between the two types of plants. In a performance assay, the development time (D) and intrinsic rate of increase (rm) of wingless aphids reared on transgenic and control plants were also similar (D, $5.8{\pm}0.2$ and $5.9{\pm}0.1$ (days) and rm, $0.7{\pm}0.1$ and $0.8{\pm}0.1$, for transgenic and control plants, respectively). These results suggest that M. persicae is not significantly affected by transgenic Bt cabbage.

• Tuberculosis and Respiratory Diseases
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• v.59 no.3
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• pp.250-256
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• 2005

Background : Fluoroquinolone drugs are an important anti-tuberculous agent for the treatment of multi-drug resistant tuberculosis. However, many drugs belonging to the fluoroquinolones have different cross resistance to each other. Methods : Sixty-three ofloxacin (OFX) resistant and 10 pan-susceptible M. tuberculosis isolates were selected, and compared for their cross resistance using a proportion method on Lowenstein-Jensen media, containing ofloxacin (OFX), ciprofloxacin (CIP), levofloxacin (LVX), moxifloxacin (MXF), gatifloxacin (GAT) and sparfloxacin (SPX), at concentrations ranging from 0.5 to $3{\mu}g/ml$. DNA extracted from the isolates was directly sequenced after amplifying from the gyrA and gyrB genes. Results : The 63 OFX resistant M. tuberculosis isolates showed complete cross resistance to CIP, but only 90.5, 44.4, 36.5 and 46.0% to LVX, MXF, GAT, and to SPX, respectively. Fifty-one of the isolates (81.0%) had point mutations in codons 88, 90, 91 and 94 in gyrA, which are known to be correlated with OFX resistance. The Gly88Ala, Ala90Valand Asp94Ala mutations in gyrA showed a tendency to be susceptible to MXF, GAT and SPX. Only 4 isolates had mutations in the gyrB gene, which did not affect the OFX resistance. Conclusion : About 60% of the OFX resistant M. tuberculosis isolates were susceptible to GAT, SPX and MXF. These fluoroquinolones may be useful in the treatment of TB patients showing OFX resistance.

• Korean Journal of Poultry Science
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• v.33 no.2
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• pp.97-103
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• 2006

Telomeres are essential for chromosome stability and are related with cell senescence, apoptosis and cancer. Even though telomere length and telomerase activity have been studied extensively, very little is known to analyze the telomere dynamics in chicken cells. This study was carried out to analyze the telomere distribution and telomerase activity of Korean Native Chicken cells along with aging. The cells were collected from brain, heart, liver, kidney and germinal tissues during physiological stages. Telomere distribution was analyzed by Quantitative-Fluorescence in situ Hybridization (Q-FISH) techniques using the chicken telomeric DNA probe. Telomerase activity was performed by Telomeric Repeat Amplification Protocol (TRAP) assay. In results, the telomeres of chicken were found at the ends of all chromosomes with the interstitial telomeres on chromosomes 1, 2 and 3. The amount of telomeres on chicken cells was decreased along with aging in most tissues. Furthermore, the telomere quantity was significantly different among tissues. The relative amount of telomeres in proliferous cells such as testis cells had much more than those of liver, brain, heart, blood and kidney cells. The telomerase activity was down-regulated in cells of brain, heart and liver tissues. Whereas gonadal cells showed a constitutive activity of telomerase during all stage of life. In conclusions, the telomere quantity and telomerase activity in chicken are closely relate to cell proliferation and tissue specificity during developmental stages and aging. There is also closely correlated between the amounts of telomeric DNA and telomerase activity in chicken tissues.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.291-295
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• 2012

The use of methylacetamide (MA) as a cryoprotective agent for freezing Korean Native Black rooster Ogye semen was examined with artificial insemination. The diluted Ogye semen with HS-1 was subjected for 2 step dilution method of cryopreservation in which the final concentration of MA was adjusted to 7.5%. The sperm viability after thawing was reduced from $95.17{\pm}0.93%$ to $55.93{\pm}1.38%$ which was confirmed by live-death analysis based on Fluorescence-Activated Cell Sorting (FACS). The rates of fertilized eggs with fresh or frozen-thawed semen were reduced from $94.98{\pm}3.93%$ to $66.36{\pm}8.43%$ at day 7 with significant difference. However, the hatching rates of experiments at day 21 did not shown difference between $92.64{\pm}2.33%$ and $90.45{\pm}8.05%$ (P<0.05). With these results, the utilization of MA for freezing of Ogye spermatozoa could affect on viability of frozen-thawed semen but not on the fertility of lain eggs and hatchability of fertilized eggs and also provide possible tools of freezing for poultry genetic resource conservation.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.17-26
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• 2016

Climate change has been regarded as one of main factors to change Korean insect pest fauna. Especially, a global warming model predicts to expand habitat for insect pests originated from tropical or subtropical regions. Two insect pests, the beet armyworm (Spodoptera exigua) and the diamondback moth (Plutella xylostella), are known to overwinter in some greenhouse conditions without diapause induction in Korea. There was a clear difference between these two insects in seasonal occurrence. P. xylostella occurred only at early spring and fall seasons, but did not occur during summer. In contrast, S. exigua maintained their occurrence from late spring to fall seasons. This study set up a hypothesis that the difference in the seasonal occurrence may be resulted from variation in susceptibility to high temperature. To test the hypothesis, heat tolerance was compared between these two insects. Exposure to $42^{\circ}C$ for 40 min killed 100% individuals of P. xylostella larvae. However, most larvae of S. exigua survived in response to $42^{\circ}C$ even for 80 min. Heat tolerance varied among developmental stages in both insects. Highest tolerant stages were $4^{th}$ instar larvae and adults for P. xylostella, but $1^{st}$ instar larvae for S. exigua. Pre-exposure to $37^{\circ}C$ for 30 min significantly increased heat tolerance in both insects. Induction of heat tolerance accompanied with significant increase of glycerol contents in the hemolymph in both insects and up-regulation of three heat shock protein expressions in S. exigua. These results suggest that the differential susceptibility to high temperature explains the disappearance of P. xylostella during summer, at which S. exigua maintains its occurrence.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.501-510
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• 2015

In this study, we investigated the onset and release of endo-dormancy under natural conditions by observing bud break characteristics in 'Fuji' apple trees using water cuttings. Through examinations of bud break rate and days to bud break, we found that the endo-dormancy of 'Fuji' apple tree continues for 70 d from 165 to 255 d after full bloom (DAFB), from late October to early January of the following year. In addition, within 20 d of first bud break, based on a final bud break rate of 60% or more, we able to identify the timing of the changeover from para-dormancy to endo-dormancy, and endo-dormancy to eco-dormancy. Analysis of the chilling requirement during the endo-dormancy period revealed that chilling accumulation up to 255 DAFB to release endo-dormancy amounted to 666 and 517 h based on the CH and Utah models, respectively. Observation of internal changes in the bud during endo-dormancy showed that flower bud differentiation begins from mid-July, and t ime of inflorescence o f the disk f lower is a vailable to f ind. The f lower buds subsequently developed slowly but steadily during endo-dormancy and in the following year in February, the developmental stage of each organ had progressed. Moreover, the flower buds of 'Fuji' apples were mostly healthy during the dormancy period, but some exhibited necrosis of flower primordium, due partial cell damage from the formation of ice crystals rather than a direct effect of the low temperature. Flower buds were formed in both the axillary buds of bourse shoots and terminal buds of spurs, but lower bud differentiation was observed for the terminal buds of spurs at rate of about 65% of total buds, which was directly related to the bud size and shoot diameter.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.341-346
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• 1999

Background: Thirty children ranging from 3 to 15 years of age underwent cardiac valve replacement at Dongsan Medical Center from 1982 to 1997. Material and Method: There were 16 boys and 14 girls. The mean age was 12.1. The underlying pathological cause for valve replacement was congenital heart disease in 17 children and acquired heart disease in 13. The valve replaced was mitral in 15 children, aortic in 11, tricuspid in 3, and combined aortic and mitral in 1. Twenty-one mechanical and 10 tissue valves were placed: primary mechanical valve have been utilized since 1985. Eight of ten patients with tissue valves have had successful second valve replacements 4 to 11 years after the initial operation. Result: The operative mortality was 6.7%, but mortality was higher among patients less than 5 years of age and patients who had previous cardiac operations. Of the 28 operative survivors, 4 patients were lost to follow-up: the remaining patients were observed for a total of 2091 patient/months(mean 74.7 months, maximum 187 months). There was one late death from dilated cardiomyopathy after mitral valve replacement in 7 year-old patient with atrioventricular septal defect. After the operation, all patients with mechanical valves were placed on a strict anticoagulant regimen with Coumadin. The actuarial survival rate was 96% at the end of the follow-up. No instance of thromboembolism or major bleeding were observed in the survivors. Conclusion: These results indicate that valve replacement can be performed with low mortality in children, and with satisfactory long-term survival.