• Journal of Plant Biology
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• v.3 no.2
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• pp.6-18
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• 1960

The present experiments were designed in order to clarify the differences between the long and short styled plants and the transgressive gradition in the degree of dimorphism among the three heterostylous species of the Polygonus, P. japonica, F. esculentum, and P. senticosa, based on investigations regarding the floral structure, ecological and physiological traits, the results of which are summarized as follows: (1) P. japonica, although it exhibits typical dimorphism, has undergone so high a differentiation between long and short styled that its long styled individuals behave as if they were female; and short styled individuals as if male. In long-styled individuals, filament, anther, and pollen grains show signs of degeneration, most of the pollen being abortive. On the other hand, in short styled individuals, the filament, anther, and pollen grains have attained remarkable development; the pollen grians are large and fertile. In short-plant the fertilized flowers readily drop off in every stage of their embryo development. This species has completely lost the self-fertile property, which is characteristic of the non-dimorphic Polygonum genus. Although this specsei typically exhibits the physiological characteristics of the non-dimorphic Polygonum genus. Although this specisei typically exhibits the physiological characteristics of dimorphism in controlled pollination, the short-styled individuals bear no seed in nature, thus misleading taxonomists to idenfity the short-styled plant as male. 2) The morphological feature of the flower organ of P. senticosa obviously indicates definite dimorphism. Physiologically, however, no differentiation towards dimorphism was observed, the species still retaining, both in long and short-individuals, the self-fertile property common to the Polygonum genus. Elaborate examinations revealed that regardless of the modes of pollination, both fertiization and seed setting flourish, no differentiation betwen legitimate and illegitimate unions being recognizable. This sort of physiological property has not been observed in the investigations of other heterostylous plants. It is assumed that this species is differentiated structurally into dimorphism, but not yet physiologically. In nature, however, this plant would have more opportunities to be cross-pollinated, i.e., legitimately combined, than self-pollinated because of the development of two forms of flowers. 3) In terms of heterostylism, the F. esculentum just occupies the intermediate position between P. japonica and P. senticosa structurally, ecologically, and physiologically. Doescription of some of the physiological behavior of the plant will suffice to demonstrate the above facts. While P. japonica has completely lost its self-fertile property, P. senticosa still retains it wolly. In F. esculentum 2-6% of self-fertility is the result in illegitimate combination. There occur occasionally hereditary self fertile individuals among some of the F. or 20 min. irradiation plot, when they reach any stage of the same bacterial population. In addition to this increase of total population in the plots with the more dose of UV light irradiation, it seems that the more dose of UV light irradiation is the more shortened the generation time of Azotobacter. Therefore, it is clear that variation of reproductive rate must be, mere or less, due to the genetic effects induced by UV light irradiation. On the other hand, the lag phase or logarithmic growth phase in nonirradiated culture is shortened prominently, and this must be due to the difference in bacterial number of the original inoculm. The generation time of Azotobacter is shortened by exogeneous treatment of nuclei acid derivatives, and the degree is greater in case of DNA derivatives than RNA dervatives. W.H. Price reported that the rate of ribose nucleic acid to protein in Staphylococcus muscae is proportional to the generation time: that is the faster the cell can form ribose nucleic acid, the more rapid its growth. This explains the shortening of generation time by exogeneous RNA derivatives in this work reasonably. On the other hand, it is well known that the desoxyribose nuclic acid content per cell is constant and independent of the generation time. A.D. Laren and W.N. Takahashi reported that the infectious RNA from TMV is 6 times as sensitive to inactivation by UV as it is in the form of intact virus, and that inactivation of infectious TMV involves onlu a local change on RNA chain. But, the effect of exogeneous DNA in this work suggests that irradiated living cell which cotain DNA bring about some change on DNA moleculs as well as RNA molecules. And if the mutagenic effects of UV take into consideration, it is very reasonable. Therefore, it is clear that the variation of the generation time by UV irradiation is, more or less, due to the genetic effects. Therefore, it seems that the shortness of the average lifewpan of Azotobacter by UV irradiation is resulted not only from the influence of the environmental conditions, but also from the variation of genetic factor of the individual.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.343-352
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• 2011

The developmental period of Laodelphax striatellus Fallen, a vector of rice stripe virus (RSV), was investigated at ten constant temperatures from 12.5 to $35{\pm}1^{\circ}C$ at 30 to 40% RH, and a photoperiod of 14:10 (L:D) h. Eggs developed successfully at each temperature tested and their developmental time decreased as temperature increased. Egg development was fasted at $35^{\circ}C$(5.8 days), and slowest at $12.5^{\circ}C$ (44.5 days). Nymphs could not develop to the adult stage at 32.5 or $35^{\circ}C$. The mean total developmental time of nymphal stages at 12.5, 15, 17.5, 20, 22.5, 25, 27.5 and $30^{\circ}C$ were 132.7, 55.9, 37.7, 26.9, 20.2, 15.8, 14.9 and 17.4 days, respectively. One linear model and four nonlinear models (Briere 1, Lactin 2, Logan 6 and Poikilotherm rate) were used to determine the response of developmental rate to temperature. The lower threshold temperatures of egg and total nymphal stage of L. striatellus were $10.2^{\circ}C$ and $10.7^{\circ}C$, respectively. The thermal constants (degree-days) for eggs and nymphs were 122.0 and 238.1DD, respectively. Among the four nonlinear models, the Poikilotherm rate model had the best fit for all developmental stages ($r^2$=0.98~0.99). The distribution of completion of each development stage was well described by the two-parameter Weibull function ($r^2$=0.84~0.94). The emergence rate of L. striatellus adults using DYMEX$^{(R)}$ was predicted under the assumption that the physiological age of over-wintered nymphs was 0.2 and that the Poikilotherm rate model was applied to describe temperature-dependent development. The result presented higher predictability than other conditions.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.67-75
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• 2001

Background : Two tumor suppressor genes, p53 and p16, which have different roles in controlling the cell cycle and inducing apoptosis, are frequently inactivated during carcinogenesis including lung cancer. Single tumor suppressor gene therapies using either with p53 or p16 have been studied extensively. However, there is a paucity of reports regarding a combined gene therapy using these two genes. Methods : The combined effect of p53 and p16 gene transfer by the adenoviral vector on the growth of lung cancer cell lines and its interactive mechanism was investigated. Results : An isobologram showed that the co-transduction of p53 and p16 exhibited a synergistic growth in hibitory effect on NCI H358 and an additive effect on NCI H23. Cell cycle analysis demonstrated the induction of a synergistic G1/S arrest by a combined p53 and p16 transfer. This synergistic interaction was again confirmed in a soft agar confirmed in a soft agar clonogenic assay. Conclusion : These observations suggest the potential of a p53 and p16 combination gene therapy as another potent strategy in cancer gene therapy.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.3
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• pp.203-208
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• 2012

Pyeongangok, a new single cross variety, is an yellow dent maize hybrid (Zea mays L.) developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2011. This hybrid, which has a high yield of grain and dry matter, was produced by crossing two inbred lines, KS160 and KS155. KS160 is the seed parent and KS155 is the pollen parent of Pyeongangok. Silking date of Pyeongangok is 2 days earlier than that of check hybrid, Jangdaok, and equal to that of another check hybrid, Kwangpyeongok. Plant height of Pyeongangok is longer than that of Jangdaok and similar to that of Kwangpyeongok. Ear numbers per 100 plants of Pyeongangok is more than that of Jangdaok. Ear length of Pyeongangok is shorter than that of Jangdaok. 100 seeds weight of Pyeongangok is lighter than that of Jangdaok. Ear rate of Pyeongangok is lower than that of Kwangpyeongok. Stay-green of Pyeonganok is not greatly different with that of Kwangpyeongok. It has moderately resistance to southern corn leaf blight (Bipolaris maydis), black streaked dwarf virus (BSDV) and corn borer. It has strong resistance to northern corn leaf blight (Exserohilum turcicum). It has resistance to lodging. Pyeongangok was evaluated for the yields of grain and dry matter at four locations from 2009 to 2011. The yield of Pyeongangok in grain was 7.66 ton/ha. The yield of Pyeongangok in dry matter was 19.80 ton/ha. The yield of Pyeongangok in total digestible nutrient (TDN) was 13.32 ton/ha. Seed production of Pyeongangok has gone well due to a good match during crossing between the seed parent, KS160, and the pollen parent, KS155, in Yeongwol.

• Journal of the Society of Disaster Information
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• v.13 no.4
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• pp.442-454
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• 2017

Biological weapon is manipulated and produced from microorganisms such as bacteria, virus, rickettsia, fungi etc. It is classified as one of the Weapons of Mass Destruction (WMD) along with chemical weapon and radiological weapon. Biological weapon has a number of operational advantages over the other WMDs including ease of development and production, low cost and possibility of covert dissemination. In this study we analyze the history of biological weapon's development and the existing biological threats. Then, we predict the social impact of biological attack based on the physical properties of biological agent and infection mechanisms. By analyzing the recognition, dispersion pattern of agents, characteristics of the diseases in the biological weapon related historical events such as Sverdlovsk anthrax accident, 2001 anthrax attack, we found out some of the facts that biological attack would not likely to be recognized rapidly, produce large number of the exposed, increase number of paients who suffed from severe respiratory illness. It would lead the public health and medical service providers to be struggled with hugh burden. Base on the facts that we found from this case study, we suggested the main capabilities of public health required to respond to bioterrorism event efficiently. Syndromic surveillance and other reporting system need to be operated effeciently so that any suspicious event should be detected promptly. the pathogen which suspected to be used should be identified through laboratory diagnostic system. It is critical for the public health agency to define potentially exposed population under close cooperation with law enforcement agencies. Lastly, massive prophylaxis should be provided rapidly to the people at need by operating human and material resources effeciently. If those capacities of public health are consistantly fortified we would be able to deal with threat of bioterrorism successfully.

• Korean Journal of Veterinary Service
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• v.28 no.2
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• pp.121-146
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• 2005

Newcastle disease (ND), infectious bronchitis (IB), low pathogenic avian Influenza (LPAI) and fowl typhoid (FT) have been known as egg drop laying diseases because of the serious layer damage from mass zone layer. In this study, such egg drop laying diseases were investigated. To access this study, we peformed to evaluate antibody titers in serum and isolated bacteria and virus from organs and feces on May, July and September in 2003. The distribution of ND from January to May, IB and LPAI from October to February of the next year, and FT from March to September were inspected by the question survey in 21 farms. ND revealed to be positive rates of 490 to 474 $(96.7\%)$ in May, 510 to 506 $(99.2\%)$ in July and 510 to 510 $(100\%)$ in September with hemagglutination inhibition (HI) test. The mean antibody titers were 10.2, 9.9 and 10.2, respectively. With regard to IB, 484 out of 490 samples $(98.7\%)$ in May, 508 of 510 $(99.6\%)$ in July and 509 of 510 $(99.8\%)$ in September showed positive results and the mean antibody titers were gradually increased with 8.2, 9.0 and 9.4, respectively. According to HI test of LPAI, the positive results were shown in 442 of 480 $(92.1\%)$, 394 of 494 $(79.8\%)$ and 402 of 483 $(83.2\%)$ in May, July and September, respectively The mean antibody titers were decreased with 4.6, 4.3 and 4.0. The distribution of LPAI also elicited the positive rates of 480 to 475 $(99.0\%)$ in May, 494 to 485$(98.2\%)$ in July, 483 to 472 $(97.7\%)$ in September as determined by ELISA and the mean S/P ratio were 2.319, 2.557 and 2.380, respectively. Compared ELISA results with HI test of LPAI the positive results were 480 to 422 $(92.1\%),\;475(99.0\%),\;494\;to\;394 (79.8\%),\;485 (98.2\%)\;and\;483\;to\;402(83.2\%),\;472(97.7\%)$. Therefore, the positive rate determined by ELISA was higher than that of HI test with 6.9, 18.4 and $14.5\%$, respectively. When performed RT-PCR for ND using organ and feces samples, the pathotypes were detected $5(15.6\%)\;in\;May,\; 2(5.3\%) in\;July,\;2(7.1\%)$ in September but there is no samples showing positive band for LPAI. In attempt to isolate Salmonella gallinarum, bacteria were obtained from 4 cases (12.5%) in May, 9 (23.6%) in July, 5 (17.8%) in September. Thus the highest rate for isolation revealed to be shown in July When evaluated the antimicrobial susceptibility to 18 isolated strains of 5. gallinarum, bacteria were sensitive to trimethoprim/sulfamethox$(61.1\%),\;kanamycin\;(55.5\%),\;ampicillin\;(55.5\%)$ and amoxacillin/clavulanic acid $(55.5\%)$, cephalothin $(50.0\%)$, but resistant to penicillin $(88.9\%)$, streptomycin $(88.9\%)$, erythromycin $(83_4\%)$ and tetracycline $(61.1\%)$. According to HI test of ND and LPAI using captured 164 wild Korean tree sparrows (Passer nontanus), the positive rates were $47.6\%\;and\;57.3\%$, and the mean HI titers were 5.32 and 4.02, respectively. 71 $(43.2\%)\;and\;58(35.3\%)$ in captured sparrows also showed more than 4 titers for HI test to ND and LPAI, respectively However, the attempt for isolation of viruses failed in all samples.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.508-517
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• 1997

Hepatitis B virus(HBV) infection is one of the major health problems in Korea and HBsAg positive rate was known to be about $5\sim15%$ in general population. This study was conducted to identify the positive rates of serum HBsAg and anti-HBs among community population regarded as having hish HBV vaccination rate than in previous decade, using EIA(Enzyme immunoassay) method, in Seo-Gu, Taegu, Korea. The study subjects were 1,160 who visited Seo-Gu Health Center for check-up serologic markers of hepatitis 3. The data were obtained from the serologic test for hepatitis markers and questionnaire survey was conducted to obtain the general characteristics, vaccination history, past history of hepatitis and other liver disease, and exposure history to risk factors of hepatitis of the study subjects. The positive rates of HBsAg and anti-HBs were 5.2% and 62.4% respectively. The positive rates of HBsAg for male and female were 6.6% and 4.3% respectively. The age was divided into two groups as group I (less than 15 years old), group II (more than 16 years old) according to the hypothesis that these two groups might be different in HBV vaccination rate. HBV vaccination rates for group I and II were 83.1% and 52.3%. The positive rates of HBsAg for group I and II were 2.6% and 6.5%. The positive rates of HBsAg for the vaccinated people of the group I and II were 2.2% and 3.5%, the positive rates of anti-HBs for the vaccinated people of the group I and II were 70.1% and 71.1% respectively. The most significant factor in positive rate of HBsAg was 'hepatitis carrier in family'. Multiple logistic regression analysis revealed that 'hepatitis history' and 'hepatitis carrier in family' were significant variables for positivity of HBsAg, and 'hepatitis B vaccination' was only a significant variable for positivity of anti-HBs.

• Childhood Kidney Diseases
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• v.7 no.2
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• pp.133-141
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• 2003

Purpose : Idiopathic Membranous Nephropathy(IMN) is a rare renal disease in children. To help better understanding of its clinical course and treatment strategies, we reviewed the clinical manifestations and pathological findings of children with IMN. Methods : Among 58 cases with MN, from 1977 to 2003, 42(72.4%) were hepatitis B virus (HBV) associated and 16(27.6%), 6 males and 10 females, were idiopathic. All cases diagnosed aster 2000 were IMN. Several clinicopathological findings(sex, onset age, proteinuria, serum albumin, cholesterol, creatinine clearance, tubulointerstitial changes, glomerular sclerosis, hypertension, renal vein thrombosis, the use of ACE inhibitor, and immunosuppressive therapy) were compared between the remission and the non-remission group of the patients with IMN. Results : The median onset age was 13.4 years. Clinical manifestations were nephrotic syn-drome(7 cases, 43.8%), gross hematuria(5 cases, 31.3%) and microscopic hematuria with proteinuria(3 cases, 18.8%). Hypertension, hypocalcemic tetany and renal vein thrombosis were accompanied in 2, 1 and 2 cases, respectively. In addition to the typical findings of MN, the kidney biopsies showed segmental sclerosis(5 cases, 31.3%) or global sclerosis(6 cases, 37.5 %), diffuse crescents(1 case), and mild(11 cases, 68.7%) or moderate tubulointerstitial changes(3 cases, 18.8%). Thirteen cases(86.7%) received oral steroid. Among them 2 cases received cyclophophamide and 1 received cyclosporin as well. Ten cases(62.5%) received ACE inhibitors. In the patients followed up, 7 cases(46.7%) became free from proteinuria (remission group) while 8(53.3%) presented continous proteinuria (non-remission group), two (13.3%) of which progressed to renal failure. Clinicopathological findings showed no significant differences between the two groups. Conclusion : With HBV vaccination, HBV associated MN decreased markedly and IMN has taken up most of MN in children. For better understanding of this rare disease, a prospective multicenter study of the clinical course and treatment strategies should be done.

• Journal of Life Science
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• v.26 no.7
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• pp.764-771
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• 2016

Extracts from Artemisia annua Linné (AAE) have been known to possess various functions, including anti-bacterial, anti-virus, and anti-oxidant effects. However, the mechanism of those effects of AAE is not well-known. The aim of this study was to analyze the inhibitory effects of AAE on cell proliferation of the human hepatoma cell line (Hep3B) and to examine its effects on apoptosis. Activation by phosphorylation of Akt is cell proliferation through the phosphorylation of TSC2, mTOR, and GSK-3β. We suggested that AAE may exert cancer cell apoptosis through Akt/mTOR/GSK-3β signal pathways and mitochondria-mediated apoptotic proteins. For this, we examined the effects of extracts of AAE on cell proliferation according to treatment concentration. Treatment with AAE not only reduced cell viability, but also resulted in the induced release of lactate dehydrogenase (LDH). These results were determined with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) assay. Furthermore, we determined the effects of apoptosis through Hoechst 33342 staining, annexinⅤ-propidium iodide (PI) staining, 5,5′, 6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide (JC-1) staining, and Western blotting. Our study showed that the treatment of liver cancer cells with AAE resulted in the inhibition of Akt, TSC2, GSK-3β-phosphorylated, Bcl-2, and pro-caspase 3 and the activation of Bim, Bax, Bak, and cleaved PARP expressions. These results indicate that AAE induced apoptosis by means of a mitochondrial event through the regulate of Akt/mTOR/GSK-3β signaling pathways.

• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.199-208
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• 2010

To investigate a comparison of rice yield and quality between organic and conventional cultivation, study for occurrence of rice diseases carried out in rice (Oryza sativa L.) field of Noahn and Bannam region. The results obtained as following: 1) Bactericide and insecticide were applied twice and four times at Noahn and Bannam region in conventional cultivation (C.C) of rice field, respectively, it was applied twice at two region in organic cultivation (O.C). Rice strip virus, leaf blast, neck blast, sheath blight, bacterial leaf blight, rice water weevil, rice leaf folder, and plant hoppers were occurred mainly in rice field. Leaf blast, neck blast, and rice leaf folder were occurred highly at O.C compared with C.C. 2) Growth level of rice in clum and panicle length was lower at O.C than C.C. Number of panicles per hill was by 0.6 higher at O.C than C.C. Number of panicles per hill was by 0.6 higher at O.C than C.C in Noahn region. Number of spikelets per panicle, grain filling ratio, brown/rough rice ratio, and weight of 1,000 grains was lower at O.C than C.C. Number of panicles per hill was by 0.8 lower at O.C than C.C in Bannam region. Number of spikelets per panicle and grain filling ratio was higher at O.C than C.C while brown/rough rice ratio was lower at O.C. Total yield percentage of rice in O.C was level of 84% at Noahn region and 94% at Bannam region compared with C.C. 3) Head rice percentage was lower at in O.C than C.C at two region. Protein and palatability (Toyo value) were lower at O.C than C.C in Bannam region causing occurrence of neck blast and rice leaf folder by oversupply of nitrogen fertilizer. Protein, whiteness, and palatability (Toyo value) were adequate level at O.C in Noahn region by lower nitrogen fertilizer.