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Genotoxicity Tests on Hyrubicin ID6105, a Novel Anthracycline Anticancer Agent (새로운 Anthracycline계 항암제 Hyrubicin ID6105에 대한 유전독성연구)

  • 장호송;정미숙;이홍섭;유정수;김태영;김윤배;강종구
    • Toxicological Research
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    • v.18 no.4
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    • pp.385-391
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    • 2002
  • The genotoxic potential of Hyrubicin lD6105, a novel anthracycline anticancer agent, was examined on bacterial mutagenicity, mammalian cell chromosome aberration and mouse micronucleus tests. In mutagenicity (Ames') test, Salmonella typhimurium strain TA98, TA100, TA1535 and TA1537, and Escherichia coli WP2uvrA- were treated with ID6105 at doses of 312.5, 625, 1,250, 2,500 and 5,000 $\mu\textrm{g}$/ plate with or without a metabolic activation system (S9 mix). Interestingly, ID6105 significantly enhanced the number of revertant colonies of TA98 strain at all dose levels used, in the presence or absence of S9 mix, without affecting other strains of S. typhimurium and E. coli. In chromosome aberration test using cultured chinese hamster lung fibroblasts, ID6105 (1.25, 2.5 and 5 $\mu\textrm{g}$/ml) did not increase the number of aberrant cells, compared with vehicle control. in the presence or absence of S9 mix. In addition, ID6105 treatment (2.5, 5 and 10 mg/kg) did not induce micronucleated polychromatic erythrocytes in mice. Taken together, it is suggested that ID6105 might not affect chromosome integrity in mammalian system in vitro and in vivo, although it may induce frame shift mutation of specific bacterial strain such os S. typhimurium TA98.

Significance of Perianal Lesion in Pediatric Crohn Disease

  • Jin, Won Seok;Park, Ji Hyoung;Lim, Kyung In;Tchah, Hann;Ryoo, Eell
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.21 no.3
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    • pp.184-188
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    • 2018
  • Purpose: Despite the increasing incidence of pediatric Crohn disease (CD) in Korea, data on the characteristics of perianal lesions are scarce. Therefore, we aimed to investigate the characteristics of pediatric CD with accompanying perianal lesions in Korea. Methods: We retrospectively reviewed the medical records of children (age ${\leq}18$ years) with confirmed CD at Gachon University Gil Medical Center between 2000 and 2014. Patients were classified into two groups based on the presence or absence of any perianal lesions including skin tags. Additional analysis was performed according to the presence or absence of perianal perforating lesions. Results: Among the 69 CD children (mean age, 15.4 years) include in the analysis, 54 (78.3%) had a perianal lesion and 29 (42.0%) had a perianal perforating lesion. The median duration of chief complaints was longer in pediatric CD with any accompanying perianal lesions (5.40 months vs. 1.89 months, p=0.02), while there was no difference between pediatric CD with and without perianal perforating lesions (5.48 months vs. 4.02 months, p=0.18). Perianal symptoms preceded gastrointestinal symptoms in 13 of 29 (44.8%) patients with perianal perforating lesions. Conclusions: CD should be suspected in children with perianal lesions, even in circumstances when gastrointestinal symptoms are absent.

Effect of calcitonin gene-related peptide, vasoactive intestinal peptide and substance P on isolated renal artery of rabbit (토끼 적출 신동맥에 대한 calcitonin gene-related peptide, vasoactive intestinal peptide 및 substance P의 효과)

  • Kim, Joo-heon;Shim, Cheol-soo;Park, Sang-eun
    • Korean Journal of Veterinary Research
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    • v.34 no.4
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    • pp.727-734
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    • 1994
  • To elucidate the effect of calcitonin gene-related peptide(CGRP), vasoactive intestinal peptide(VIP) and substance P was investigated with perivascular nerve stimulation and treatment of peptides from polygraph in the isolated renal artery of rabbit. 1. The neurogenic contraction induced by perivascular nerve stimulation was the frequency-dependent manner(264 Hz) in the isolated renal artery of rabbit. 2. CGRP and VIP caused the relaxation on the precontraction with noradrenaline($10{\mu}m$) on the presence and absence of endothelium in the isolated renal artery of rabbit. 3. Substance P caused the endothelium-dependent relaxation on the precontraction with noradrenaline($10{\mu}m$) in the isolated renal artery of rabbit. 4. CGRP and VIP inhibited the neurogenic contraction by the perivascular nerve stimulation(0.3 ms, 80 V, 50 Hz, 1 sec) on the absence and presence of endothelium in the isolated renal artery of rabbit. 5. Substance P inhibited on the neurogenic contraction by the perivascular nerve stimulation with the endothelium-dependent in the isolated renal artery of rabbit.

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Neural Mechanism in Bronchial Asthma (기관지천식에서의 신경적 기전)

  • Choi, Byoung-Whui
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.2
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    • pp.73-86
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    • 1994
  • In addition to classic cholinergic and adrenergic pathways, the existence of a third division of autonomic control in the human airways has been proved. It is called a nonadrenergic noncholinergic(NANC) nervous system, and difficult to study in the absence of specific blockers. Neuropeptides are certainly suggested to be transmitters of this NANC nervous system. It is very frustrating to understand the pathophysiologic role of these peptides in the absence of any specific antagonists. However, further studies of neuropeptides might eventually lead to novel forms of treatment for bronchial asthma. Another study of the interaction between different components of the autonomic nervous system, either in ganglionic neurotransmission or by presynaptic modulation of neurotransmitters at the end-organ will elute neural control in airway disease, particularly in asthma. Studies of how autonomic control may be disordered in airway disease should lead to improvements in clinical management. Epithelial damage due to airway inflammation in asthma may induce bronchial hyperresponsiveness. Axon reflex mechanism is one of possible mechanisms in bronchial hyperresponsiveness. Epithelial damage may expose sensory nerve terminals and C-fiber nrve endings are stimulated by inflammatory mediators. Bi-directional communication between the nerves and mast cells may have important roles in allergic process. The psychological factors and conditioning of allergic reactions is suggested that mast cell activation might be partly regulated by the central nervous system via the peripheral nerves. Studies in animal models, in huamn airways in vitro and in patients with airway disease will uncover the interaction between allergic disease processes and psychologic factors or neural mechainsms.

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Eye-Tracking on Inservice Elementary Teachers' Interpreting of Science Textbook Tables (과학 교과서의 표를 해석하는 초등교사들의 안구 운동 추적)

  • Choi, Hyun-Dong;Shin, Dong-Hoon
    • Journal of Korean Elementary Science Education
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    • v.31 no.3
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    • pp.358-371
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    • 2012
  • The main purpose of this study was to examine elementary teachers' visual attention that appears in science textbook tables. This paper proposed that teachers' cognitive effectiveness can be different by the presence or absence of the title of tables. The eye fixation data of participants are collected by the eye tracker apparatus. Participants in this study were 10 elementary school teachers and the table on the 2007 revised science textbooks were selected as experimental stimuli. Information about eye-fixations are recorded when subjects are given 4 tables by eye tracker. Eye-fixation time as well as the ratio and the number of fixation can be obtained by using the eye tracker but also we can acquire a significant conclusion through these outcomes. As the result of the experiment, it took less time to interpret in the presence of the title than in the absence of it. However, this result is only effective only for the interpretation of simple stimulus; the presence of title does not influence on fixation time in the analysis of complicated stimulation. This study showed that it is better to insult the title in the tables because it helps teachers to recognize contents of the tables effectively.

Kinetics of Denaturation of Human and Chicken Hemoglobins in the Presence of Co-solvents

  • Ajloo, Davood;Moosavi-Movahedi, Ali A.
    • BMB Reports
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    • v.36 no.4
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    • pp.367-372
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    • 2003
  • The stability of four hemoglobins (Hb) in dimer forms (low concentration) were investigated by the kinetics of denaturation. The rate constants of denaturation were obtained by variation of 280 nm absorption versus time in 10 mM Tris-HCl, 10 mM EDTA, pH 8.0 at $45^{\circ}C$ in the absence and presence of 0.5 M ethanol, dimethyl sulfoxide (DMSO), formamide, and glycerol. The results show the trend of rate constants in different co-solvents in the following order: chicken hemolysate < human hemolysate and chicken Hb D < chicken Hb A. The buried surface area was calculated for Hb samples in the absence of cosolvents. Accordingly, the trend points out that: chicken Hb D > chicken Hb A > human Hb A. These results suggest that both chicken hemolysate and chicken Hb D are relatively more stable than human and chicken Hb A, respectively. However, the denaturation rate constants of Hb in different co-solvents have designated the following order: ethanol > DMSO > formamide > glycerol. As a matter of fact, this phenomenon is an indication of an increase in the denaturation capacity (DC) and hydrophobicity, and a decrease in the surface tension of the solution in the preceding co-solvents.

FRICTIONAL FORCES IN THE FIXED ORTHODONTIC APPLIANCE DURING TOOTH MOVEMENT (고정성 교정장치를 이용한 치아이동시 발생되는 마찰력)

  • Cho, Myeong-Sook;Kim, Jong-Chul
    • The korean journal of orthodontics
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    • v.20 no.2
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    • pp.409-417
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    • 1990
  • Tooth movement would be impeded by frictional force arised between archwire and tube, bracket or elastics in the fixed orthodontic appliances, which could be changed variably by such several factors as the contact area, normal (perpendicular) force and the condition of contact surface. There were many literatures about frictional force in the orthodontic region, but different results were obtained from little controlled research so that was very difficult in clinical application. Therefore we have reviewed comprehensively previous literatures about frictional force and thus several results were obtained as follows: 1. For use species of the orthodontic wire, frictional force was influenced mainly by surface roughness of wire in the absence of binding, while that was influenced mainly by normal force in high binding angulation. 2. For the cross-section and diameter of the wire, the contact area influenced mainly on frictional force in the absence of binding, while wire stiffness influenced mainly on frictional force in high binding angulation. 3. The greater the bracket width, the greater frictional force, and frictional force of the plastic bracket was larger than that of the metal bracket. 4. For ligation type, frictional force of the stainless steel ligation was larger than that of the elastic ligation, and frictional force was directly proportional to ligation force. 5. Variable frictional force were occured from the saliva combined with such another factors as normal force and mode of surface oxide et al.

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PRIMARY INTRAOSSEOUS CARCINOMA ON MANDIBLE : A CASE REPORT (하악골에 발생한 원발성 골내암종의 치험례)

  • Kim, Hak-Ryeol;Ryu, Dong-Mok;Oh, Jung-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.3
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    • pp.263-267
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    • 2007
  • Primary intraosseous carcinoma (PIOC) is a rare odontogenic carcinoma defined as a squamous cell carcinoma arising within a jaw having no initial connection with the oral mucosa, and probably developing from residues of the odontogenic epithelium. PIOC appears more common in male than female, especially at posterior portion of the mandible. Radiographic features of PIOC show irregular patterns of bone destruction with ill defined margins. It could be sometimes misdiagnosed as the cyst or benign tumor because it shows well defined margins. If it couldn't be done appropriate treatment initially, PIOC shows extremely aggressive involvement, extensive local destruction and spreads to the overlying soft tissue. Therefore accurate diagnosis in early state is necessary. The diagnosis criteria proposed for PIOC are : (1) absence of ulcer formation, except when caused by other factors, (2) histologic evidence of squamous cell carcinoma without a cystic component or other odontogenic tumor cell, and (3) absence of another primary tumor on chest radiograph obtained at the time of diagnosis and during a follow-up period of more than 6 month(Suei et al., 1994).

Rescue of Oxidative Stress by Molecular Chaperones in Yeast

  • Ueom Jeonghoon;Kang Sooim;Lee Kyunghee
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2002.10a
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    • pp.76-78
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    • 2002
  • Heat shock proteins (HSPs) are induced in most living cells by mild heat treatment, ethanol, heavy metal ions and hypoxia. In yeast Saccharomyces cerevisiae, mild heat pretreatment strongly induces Hsp104 and thus provide acquired thermotolerance. The ability of hsp104 deleted mutant $({\triangle}hsp104)$ to acquire tolerance to extreme temperature is severely impaired. In providing thermotolerance, two ATP binding domains are indispensible, as demonstrated in ClpA and ClpB proteases of E. coli. The mechanisms by which Hsp104 protects cells from severe heat stress are not yet completely elucidated. We have investigated regulation of mitochondrial metabolic pathways controlled by the functional Hsp104 protein using $^{13}C_NMR$ spectroscopy and observed that the turnover rate of TCA cycle was enhanced in the absence of Hsp104. Production of ROS, which are toxic to kill cells radiply via oxidative stress, was also examined by fluorescence assay. Mitochondrial dysfunction was manifested in increased ROS levels and higher sensitivity for oxidative stress in the absence of Hsp104 protein expressed. Finally, we have identified mitochondrial complex I and Ferritin as binding protein(s) of Hsp104 by yeast two hybrid experiment. Based on these observations, we suggest that Hsp104 protein functions as a protector of oxidative stress via either keeping mitochondrial integrity, direct binding to mitochonrial components or regulating metal-catalyzed redox chemistry.

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The Taxonomy of Psilocybe fagicola-complex

  • Guzmanl Gaston;Jacobs James Q.;Florencia Ramirez Guillenl;Murrietal Dulce;Gandaral Etelvina
    • Journal of Microbiology
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    • v.43 no.2
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    • pp.158-165
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    • 2005
  • Psilocybe fagicola comprises a complex of more than eight species, six of them in Mexico, and all of them possessing a long pseudorhiza, a characteristic not listed by Heim and Cailleux in 1959 in the original description of the type species, but described by Guzman in 1978 and 1983. The description of Psilocybe fagicola s.s. is here emended to include the length of the cheilocystidia of(6-) 12-20 (-30) llm, as well as the absence or scarcity of pleurocystidia. Psilocybe xalapensis and P. wassoniorum are considered to be synonymous with P. fagicola s.s. However, Psilocybe banderillensis and P. herrerae from Mexico, P. columbiana from Colombia, and P. keralensis from India are considered to be valid species within this complex. Moreover, P. novoxalapensis and P. teofilae, both from Mexico, are described as new species. Length of spores, presence or absence of pleurocystidia and their variations, and type of cheilocystidia constitute the principal defining characteristics of the species. Setaceous hyphae at the base of the stipe, as well as caulocystidia, lack taxonomic value, as do other morphological characteristics, including pileipellis and subpileipellis. A key to the eight considered species is also presented within the paper.