• Applied Microscopy
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• v.24 no.2
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• pp.78-92
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• 1994

Lysozyme has been reported to be present in the secretory granules of the Paneth cell, and lysozyme immunoreactivity has been detected by immunogold method in Paneth cells of the intestine of human, mouse and rat. The present study was aimed at clarifying the intracellular distribution and changes of the lysozyme immunoreactivity in rabbit Paneth cell after common bile duct ligation of rabbit, using the electron microscope immunogold technique. Healthy adult rabbits weighing about 2kg body weight were divided into normal and bile duct ligated groups. Common bile duct ligation was performed aseptically under ether anesthesia. Experimental animals were sacrificed on the 1st, the 3rd, the 5th, the 7th and the 14th day after the operation. Mucosal specimens from the intestinal gland of ileum were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde, followed by 1% osmium tetroxide, embedded in araldite mixture, cut with LKB-V ultratome. Ultrathin sections were placed on parlodion coated nickel grids (200mesh). The section-bearing grids were floated upside down on the added substance in a moist chamber at room temperature except for the primary antibody step, which was at $4^{\circ}C$. Sections were etched with a saturated solution of sodium m-periodate for 60min. After etching, sections were pretreated with 0.02M tris buffered saline (TBS), pH 8.4, with 1% bovine serum albumin (BSA, Sigma) for 60min, then treated polyclonal rabbit anti-human lysozyme (Dakipatts) diluted 1 : 50 in TBS with 0.1% BSA for 20hr. Subsequently, grids were incubated 60min in biotinylated goat anti rabbit IgG (Amersham) diluted 1 : 100 in TBS with 0.1% BSA. After this, sections were incubated 60min on streptavidin gold G10 (Amersham) diluted 1 : 50 in TBS with 0.1% BSA. After each step, the grids were briefly rinsed with TBS with 0.1% BSA. After the strepavidin gold step, the sections were jet washed with distilled water. Counterstain of the sections performed by uranyl acetate and lead citrate, and observed with JEM 100 CX II electron microscope. Observed results were as follow; 1. Secretory granules of mouse Paneth cells have a lysozyme immunoreactivity and also eosinophil leucocyte of rabbit applied for the positive-control stain, are well labeld with gold particles. 2. Normal rabbit Paneth cells have a lysozyme immunoreactivity restricted on the secretory granules. 3. Amount lysosomes containing myelin figures in the Paneth cells were significantly increased from 5th day after the common bile duct ligation. 4. Immunoreactivity of Paneth cell secretory granules were more activated on the 3rd day after the common bile duct ligation as compared with those of the normal animal. But the lysozyme immunoreactivity were decreased from the 5th day after the common bile duct ligation. 5. Considering the above finding, lysozyme contained Paneth cell are affected following of common bile duct ligation, whereas lysosomes containing myelin-figure do not exhibit any immunoreactive relationship with those of secretory granules.

• Research in Plant Disease
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• v.12 no.1
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• pp.15-19
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• 2006

This study was carried out to know pathogenicity of the pathogen isolated in several location of Korea and penetration mechanism of the Pseudocercospora vitis ($(L\acute{e}v)$.) Speg. Inoculation tests at room temperature were performed on both sides of leaves with different isolates of the fungus. The typical symptoms appeared on the abaxial leaf surface, but no symptom was observed on the adaxial leaf surface with all isolates. The average incubation period was nine days, since all symptoms appeared from 8 to 10 days after inoculation. In order to know the mechanism of invasion of P. vitis to grapevine, the behavior of penetration hyphae through stomata were compared in two cultivars having different level of resistance. In order to know the mechanism of resistance of grape vine to P.vitis, two cultivars having different level of resistance were compared by counting the numbers and measuring size of the stomata per leaf. In a susceptible cultivar Campbell Early, the number of stomata was more than that of a resistance cultivar 'Kyoho'. In a susceptible cultivar 'Campbell Early', the fungus entered readily into stomata after inoculation. However, in a resistant cultivar 'Kyoho', the fungus seemed to pass over or surrounded only the guard cells. In comparison of height of guard cells of stomata between the two cultivars, significant differences were observed by scanning electron microscopy and light microscopy. The height of guard cells of 'Campbell Early' showed a little higher than those of 'Kyoho' known to be resistant to the fungus.

• Toxicological Research
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• v.33 no.2
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• pp.107-118
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• 2017

Although alternative test methods based on the 3Rs (Replacement, Reduction, Refinement) are being developed to replace animal testing in reproductive and developmental toxicology, they are still in an early stage. Consequently, we aimed to develop alternative test methods in male animals using mouse spermatogonial stem cells (mSSCs). Here, we modified the OECD TG 489 and optimized the in vitro comet assay in our previous study. This study aimed to verify the validity of in vitro tests involving mSSCs by comparing their results with those of in vivo tests using C57BL/6 mice by gavage. We selected hydroxyurea (HU), which is known to chemically induce male reproductive toxicity. The 50% inhibitory concentration ($IC_{50}$) value of HU was 0.9 mM, as determined by the MTT assay. In the in vitro comet assay, % tail DNA and Olive tail moment (OTM) after HU administration increased significantly, compared to the control. Annexin V, PI staining and TUNEL assays showed that HU caused apoptosis in mSSCs. In order to compare in vitro tests with in vivo tests, the same substances were administered to male C57BL/6 mice. Reproductive toxicity was observed at 25, 50, 100, and 200 mg/kg/day as measured by clinical measures of reduction in sperm motility and testicular weight. The comet assay, DCFH-DA assay, H&E staining, and TUNEL assay were also performed. The results of the test with C57BL/6 mice were similar to those with mSSCs for HU treatment. Finally, linear regression analysis showed a strong positive correlation between results of in vitro tests and those of in vivo. In conclusion, the present study is the first to demonstrate the effect of HU-induced DNA damage, ROS formation, and apoptosis in mSSCs. Further, the results of the current study suggest that mSSCs could be a useful model to predict male reproductive toxicity.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.85-98
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• 1995

Six malformin B's produced by Aspergillus niger van Tiegh. were separated by HPLC. Their structures determined by the methods of amino acid analyses, mass spectrometry, and two-dimensional NMR were revealed as cyclic pentapeptides structurally related to malformin $A_1$. Both the NMR and MS/MS data suggest that the respective structures of separated malformin B's were as follows; cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-allo-Ile for $B_{1a}$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Leu for $B_{1b}$, cyclo-D-Cys-D-Cys-L-Val-D-Val-L-Leu for $B_2$, cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Leu for $B_3$, cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Ile for $B_4$, and cyclo-D-Cys-D-Cys-L-Val-D-Val-L-Ile for $B_5$. Among the malformin B's, the structure of $B_{1b}$ was the same as that of malformin $A_3$ or C. All the malformin B's showed physiological activities in the two assay systems using corn(Zea mays L.) roots and mung bean(Phaseolus aureus Roxb.) hypercotyl segments. The malformin B's with molecular weight 529 were more effective for inducing corn root curvature than those with molecular weight 515. The difference in molecular weight of malformin B's, i.e., the retention time on HPLC, results in the polarity change of the whole malformin molecule which affects the revealation of the malformin activities. In addition, the disulfide form of the malformin B's gives the rigidity of the molecule, whereas the combination of the fourth and the fifth amino acid residues provides the optimal three-dimensional configuration to the malformin receptor of plants. Presumably, these two factors are appeared to be essential for the greatest physiological activity of malformin B's. malformin $B_{1a}$ caused the corn root curvature by 90% at a concentration of $0.25{\mu}M$. However, such differential activities with molecular weight of 529 or 515 of malformin B's were not found in the mung bean hypercotyl segment test. Maximum stimulation of mung bean hypercotyl growth was observed at $0.1{\mu}M$ concentration of malformin B's. The growth of the segments treated with $B_5$ was 154% greater than that of the control.

• Applied Microscopy
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• v.35 no.3
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• pp.135-152
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• 2005

Prefrontal cortex is a psychological and metaphysical cortex, which deals with feeling, memory, planning, attention, personality, etc. And it also integrates above-mentioned events with motor control and locomotor activities. Prefrontal cortex works as a highest CNS center, since the above mentioned functions are very important for one's successful life, and further more they are upgraded every moments through memory and learning. Many of these highest functions are supposed to be generated via forebrain basal nuclei (caudate nucleus, fundus striati nucleus, accumbens septi nucleus, septal nucleus, etc.). In this experiment, prefrontal efferent terminals within basal forebrain nuclei were ultrastructurally studied. Spraque Dawley rats, weighing $250{\sim}300g$ each, were anesthetized and their heads were fixed on the stereotaxic apparatus (experimental model, David Kopf Co.). Rats were incised their scalp, perforated a 3mm-wide hole on the right side of skull at the 11mm anterior point from the frontal O point (Ref. 13, Fig. 1), suctioned out the prefrontal cortex including cortex of the frontal pole, with suction instrument. Two days following the operations, small tissue blocks of basal forebrain nuclei were punched out, fixed in 1% glutaraldehyde-1% paraformaldehyde solution followed by 2% osmium tetroxide solutions. Ultrathin sections were stained with 1% borax-toluidin blue solution, and the stained sections were obserbed with an electron microscope. Degenerating axon terminals were found within all the basal forbrain nuclei. Numbers of degenerated terminals were largest in the caudate nucleus, next in order, in the fundus striati nucleus, in the accumbens septi nucleus, and the least in the septal nucleus. Only axospinous terminals were degenerated within the caudate nucleus and the fundus striati nucleus, and they showed the characters of striatal motor control system. Axodendritic and axospinous terminals were degenerated within the accumbens septi nucleus and the lateral septal nucleus, and they showed the characters of visceral limbic system. Prefrontal role in integrating the limbic system with the striatal system, en route basal forebrain nuclei, was discussed.

• Journal of Biosystems Engineering
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• v.4 no.1
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• pp.1-23
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• 1979

The use of barley seeder attached to rotary tiller in the rural area has a significant meaning not only for the solution of labor peak season, but also for the increase of land utilization efficiency. The facts that presently being used barley seeders are all based on the mechanical principles of the reverse rotation, center drive and are all using forward rotating tine, which is used to be easily and heavily worn out when it rotates reversely, raise problem of recommending them to rural area in Korea. Therefore, the main objective of the study was to develop new type of rotary tine attachable to barley seeders. To attain the objective the following approaches were applied. (1) The kinematic analysis of reverse rotating barley seeders. (2) The studies on the soil bin and artificial soil. (3) The comparative experiment on the power requirement of prototype tine. The results obtained from the studies are summarized as follow: 1. The kinematic analysis of barley seeder attached to rotary tiller: The following results were obtained from the kinematic analysis for deriving general formulae of the motion and velocity characterizing the rotary tine of barley seeders presently being used by farmers. a) The position vector (P) of edge point (P) in the rotary tine of reverse rotating, center drive was obtained by the following formula. $$P=(vt+Rcos wt)i+Rsin wt j+ \{ Rcos \theta r sin \alpha cos (wt- \beta +\theta r) +Rsin \theta r sin \alpha sin (wt-\beta + \theta r) \} lk $$ b) The velocity of edge point $(P^')$ of reverse rotating, center drive rotary tine was obtained by the following formula. $$(P^')=(V-wR sin wt)i+(w\cdot Rcoswt)j + \{ -w\cdot Rcos \theta r\cdot sin \alpha \cdot sin (wt-\beta +\theta r) + w\cdot Rsin \theta r\cdot sin \alpha \cdot cos (wt- \beta + \theta r \} k $$ c) In order to reduce the power requirement of rotary tine, the angle between holder and edge point was desired to be reduced. d) In order to reduce the power requirement, the edge point of rotary tine should be moved from the angle at the begining of cutting to center line of machine, and the additional cutting width should be also reduced. 2. The studies on the soil bin and artificial soil: In order to measure the power requirement of various cutting tines under the same physical condition of soil, the indoor experiments Viere conducted by filling soil bin with artificially made soil similar to the common paddy soil and the results were as follows: a) When the rolling frequencies$(x)$ of the artificial soil were increased, the densIty$(Y)$ was also increased as follows: $$y=1.073200 +0.070780x - 0.002263x^2 (g/cm^3)$$ b) The absolute hardness $(Y)$ of soil had following relationship with the rolling frequencies$(x)$ and were increased as the rolling frequencies were increased. $$Y=37.74 - \frac {0.64 + 0.17x-0. 0054x^2} {(3.36-0.17x + 0.0054x^2)^3} (kg/cm^3)$$ c) The density of soil had significant effect on the cohesion and angle of internal friction of soil. For instance, the soil with density of 1.6 to 1.75 had equivalent density of sandy loam soil with 29.5% of natural soil moisture content. d) The coefficient of kinetiic friction of iron plate on artificial soil was 0.31 to 0.41 and was comparable with that of the natural soil. e) When the pulling speed of soil bin was the 2nd forward speed of power tiller, the rpm of driving shaft of rotary was similar to that of power tiller, soil bin apparatus is indicating the good indoor tester. 3. The comparative experiment on the power requirement of prototype tine of reverse rotating rotary: According to the preliminary test of rotary tine developed with various degrees of angle between holder and edge pcint due to the kinematic analysis, comparative test between prototype rotary tine with $30 ^\circ $ and $10 ^\circ$ of it and presently being used rotary tine was carried out 2nd the results were as follows: a) The total cutting torque was low when the angle between holder and edge point was reduced. b) $\theta r$ (angle between holder and edge point) of rotary tine seemed to be one: of the factors maximizing the increase of torque. c) As the angle between holder and edge point ($\theta r$) of rotary tine was $30 ^\circ $ rather than $45 ^\circ $, the angle of rotation during cutting soil was reduced and the total cutting torque was accordingly reduced about 10%, and the reduction efficiency of total cutting torque was low when the angle between holder and edge point ($\theta r$) of rotary tine was $10 ^\circ $, which indicates that the proper angle between holder and edge point of rotary tine should be larger than $10 ^\circ $ and smaller than $30 ^\circ $ . From above results, it could be concluded that the use of the prototype rotary tine which reduced the angle between holder and edge point to $30 ^\circ $, insted of $45 ^\circ $, is disirable not only decreasing the power requirements, but also increasing the durabie hour of it. Also forward researches are needed, WIlich determine the optimum tilted angle of rotary brocket, and rearrangement of the rotary tine on the rotary boss.

• KSBB Journal
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• v.18 no.6
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• pp.522-528
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• 2003

The purpose of this study is to inquire into molecular epidemiological characteristics of Vibrio parahaemolyticus. For this study, 120 strains(120 strains of Vibrio parahaemolyticus sampled from diarrhea patients) were examined and analyzed for biochemical characteristics, TDH (thermostable direct hemolysin) antibiotics sensitivity and detection of toxR, gyrE, tdh, and tds gents. G-S PCR (Group Specific Polymerase), PFGE (Pulsed-field Gel Electrophoriesis) methods were performed on the materials from patients were results. 1 Vibrio parahaemolyticus didn't grow in 0% density of NaCl, but the fact was found that those grew in 8% density of NaCl. 2. O：K serotypes of Vibrio parahaemolyticus was turned up in domestic patients was 17 types. Among those O3：K6 was the most, it was 68.3%. 3. In 18 kinds of antibiotic tests resistant against Ampicillin, Ticacillin was comparatively high. the case of resistant against Ampicillin, Ticacillin, Vancomycin at the multiple resistant was 52.5%. 4. Toxin gene tdh had only 109 strains among 120 ones isolated from patients held the genes of 199bp size, and 11 strains was negativity 5. In the test of Kanagawa toxic productivity, 107 strains among strains isolated from patients appeared to be positivity reaction 6. The strain that held trh toxin was only 3, and those among test strains had the genes of 250bp size and that had tdh, trh genes at a time were 3 strains, and TDH toxic productivity of those were 16 times, and it was weak. 7. Group Specific-PCR appeared to be useful in the confirmation of O3:K6 serotype interrelations. 8. Three strains which showed difference of 7 DNA sequence even in the same serotype were detected by the result of analyzing the regular gene, toxRS DNA sequence. These strains are differ from general strains which carry infection easily. 9. These mutual dose epidemiological relations were classified into smaller-parts through PFGE method. As a result of such classify, 3 findings were found. V. parahaemolyticus sampled from diarrhea patients were classified into 3 types. And third, the result obtained through PFGE method can be used as a useful tool in a point of molecular-epidemiological view.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.13-20
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• 2008

The flow rate measurements in a multi-phase flow pipeline were evaluated quantitatively by means of a clamp-on sealed radioisotope based on a cross correlation signal processing technique. The flow rates were calculated by a determination of the transit time between two sealed gamma sources by using a cross correlation function following FFT filtering, then corrected with vapor fraction in the pipeline which was measured by the ${\gamma}$-ray attenuation method. The pipeline model was manufactured by acrylic resin(ID. 8 cm, L=3.5 m, t=10 mm), and the multi-phase flow patterns were realized by an injection of compressed $N_2$ gas. Two sealed gamma sources of $^{137}Cs$ (E=0.662 MeV, ${\Gamma}$ $factor=0.326\;R{\cdot}h^{-1}{\cdot}m^2{\cdot}Ci^{-1}$) of 20 mCi and 17 mCi, and radiation detectors of $2"{\times}2"$ NaI(Tl) scintillation counter (Eberline, SP-3) were used for this study. Under the given conditions(the distance between two sources: 4D(D; inner diameter), N/S ratio: $0.12{\sim}0.15$, sampling time ${\Delta}t$: 4msec), the measured flow rates showed the maximum. relative error of 1.7 % when compared to the real ones through the vapor content corrections($6.1\;%{\sim}9.2\;%$). From a subsequent experiment, it was proven that the closer the distance between the two sealed sources is, the more precise the measured flow rates are. Provided additional studies related to the selection of radioisotopes their activity, and an optimization of the experimental geometry are carried out, it is anticipated that a radioisotope application for flow rate measurements can be used as an important tool for monitoring multi-phase facilities belonging to petrochemical and refinery industries and contributes economically in the light of maintenance and control of them.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.193-202
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• 2006

The Consultative Meeting of the Convention on the Prevention of Marine Pollution by Dumping of Wastes and other matter, 1972 (London Convention 1972) has requested to International Maritime Organization (IMO) Marine Environmental Protection Committee to collaborate and help clarify a boundary issue between International Convention for the Prevention of Pollution from Shops, 1973 as modified by the Protocol of 1978 (MARPOL) and the London Convention concerning 'dumping' versus 'discharges' during normal operations of ships in 2004, and subsequently established a Joint London Convention/MEPC Correspondence Group. The Contracting Parties to London Convention expressed their environmental concerns on the broad interpretation of the "cargo-associated wastes" by the States, which could be discharged by ships under MARPOL. Regulatory regimes for the cargo residues appear to vary among states. Some countries require fur ships to discharge their cargo wastes into the port reception facility and IMO also recommends doing so. This paper examines the related current national and international legal texts for the regulation of disposal of wastes from ships in order to analyze the current global concern on the marine pollution associated with waste discharge during operations of ships. In particular, we attempt to evaluate the likely marine environmental consequences arising from the disposal of cargo residue using an hypothetical case for the coal cargo residue among bulk cargos in this paper, since location, magnitude and frequency of the discharge of coal cargo residues into the sea adjacent to Korean Peninsula are not readily available. The cargo residues may be discharged to the sea according to MARPOL 73/78; however, its marine environmental consequences can be significant depending upon the characteristics and amounts of wastes to be discharged. Also the public tolerance of the environmental consequences would be widely different among nations. Multilateral environmental agreements, in general, more strictly apply their rules if there are other options to disposal at sea, i.e. port reception facility in this case. Therefore, port reception facilities for the wastes generated by ships are recommended to be further constructed in major national ports in order to reduce the risk of environmental damages during the operations of ships.

• Food Science and Preservation
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• v.24 no.5
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• pp.707-713
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• 2017

The objective of this study was to select yogurt starter from Korean traditional fermented foods. The 2 strains (KM24, KM32) among 50 strains of isolated lactic acid bacteria selected as starter based on milk clotting ability, antimicrobial activity against various pathogens, tolerance in artificial gastric and bile juice and growth in 10 % skimmed milk. The strains were identified as Lacobacillus plantarum (KM32) and Pediococcus pentosacesus (KM24) by 16S rRNA gene sequencing. Viable cell number of yogurt fermented with mixed strains (KM24 and KM32) was 9.66 log CFU/mL after fermentation for 48 h and maintained $10^9CFU/mL$ during fermentation for 72 h at $37^{\circ}C$. The pH and titratable acidity of mixed cultured yogurt were 4.25% and 0.83% after fermentation for 48 h at $37^{\circ}C$, respectively. The physico-chemical characteristics of mixed cultured yogurt after fermentation for 48 h were $38.45{\mu}g/mL$ (polyphenol content), 48.57% (DPPH radical scavenging activity) and 465.40 cp (viscosity), respectively. The mixed cultured yogurt maintained $10^9CFU/mL$ of lactic acid bacteria during storage 10 days at $4^{\circ}C$. The viable cell number of yogurt prepared with mixed culture(KM32+KM24) maintained higher and than that of control (L. casei) during storage. These results indicated the potential use of selected strains (KM32+KM24) isolated from kimchi as a yogurt starter with strong acid tolerance and probiotics properties.