• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.132-138
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• 2002

Non-human primates are widely used for experimental animal and raised as companion animal in Korea. To establish the electrocadiogram (ECG) of non-human primates that are domestically raised, the author measured bipolar limb leads and augmented unipolar limb leads, after tiletamine/zolazepam (TZ) injection as sedative agents. The amplitudes of P,Q, R,S and T wave and duration time of P wave, QRS complex, PR and QT interval in each lead of ECG were evaluated in 7 non-human primates at 15 minutes after TZ injection, respectively. The amplitude of P wave in I, II,III, aVR, aVL and aVF leads revealed 0.06$\pm$ 0.05,0.14$\pm$ 0.05, 0.1 $\pm$ 0.05,-0.11 $\pm$ 0.06,-0.04$\pm$ 0.04 and 0.12$\pm$ 0.05 mV respectively. The amplitude of Q wave revealed -0.16$\pm$ 0.15, -0.23$\pm$ 0.18, -0.17$\pm$ 0.13, 0.16$\pm$0.13, 0.04$\pm$ 0.09 and -0.2$\pm$0.13 mV, respectively. The amplitude of R wave revealed 0.56$\pm$0.56, 1.24$\pm$ 0.67, 0.92$\pm$0.33, -0.37$\pm$ 1.14, -0.22$\pm$ 0.47 and 1.12 $\pm$ 0.47 mV, respectively. The amplitude of S wave revealed -0.02$\pm$ 0.08, -0.04$\pm$0.06, -0.06$\pm$0.04, 0.02$\pm$0.04, 0.04$\pm$0.09 and -0.04 $\pm$ 0.06 mV, respectively. The amplitude of T wave revealed -0.01 $\pm$ 0.15,-0.02$\pm$ 0.13, 0.01 $\pm$ 0.08, 0.02$\pm$ 0.12, 0.01 $\pm$ 0.11 and -0.03$\pm$ 0.09 mV, respectively. The duration time of P wave revealed 0.05 $\pm$ 0.01, 0.04$\pm$ 0.01, 0.05$\pm$ 0.02, 0.05 $\pm$ 0.02, 0.04$\pm$ 0.01 and 0.04$\pm$ 0.01 sec, respectively. The duration time of QRS complex revealed 0.05 $\pm$ 0.02,0.05$\pm$ 0.01, 0.05 $\pm$ 0.01, 0.04$\pm$ 0.01, 0.05$\pm$ 0.01 and 0.05 $\pm$ 0.01 sec, respectively. The duration time of PR interval revealed 0.08$\pm$ 0.01, 0.07$\pm$0.01,0.08$\pm$ 0.03, 0.08$\pm$0.01, 0.08$\pm$ 0.01 and 0.08$\pm$0.01 sec, respectively. The duration time of QT interval revealed 0.23$\pm$ 0.06, 0.22$\pm$ 0.05, 0.23 $\pm$ 0.06, 0.23$\pm$ 0.06, 0.24$\pm$ 0.05 and 0.22$\pm$ 0.02 sec, respectively. No significant changes were observed in e amplitude of P and T waves. The amplitude of QRS complex in ketamine group was higher than that of TZ group. However, no significant changes were observed in both intra-group and inter-group. There were no significant changes in the duration time of P wave, QRS complex and PR interval obtained from both groups. Also, the duration time of QT interval in TZ group was significantly longer at 30 min.(P< 0.05) an that of 10 minutes after injection. However, significant difference was not found between two groups. The mean cardiac electric axis in ketamine group tended to decrease until 30 min. after injection and then gradually increase. However, mean cardiac electric axis of TZ group was increased until 30 min. after injection and then decreased. But significant differences were not observed between groups. These results suggest that the ECG pattern after TZ injection to non-human primates reared in korea was established. It was also considered that the injection of ketamine and TZ didn't significantly affect on ECG pattern of the non-human primates.

• Journal of Biomedical Engineering Research
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• v.33 no.2
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• pp.72-77
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• 2012

Phase Contrast MR Angiography(PC MRA) is excellent MRA technique for measuring the velocity of vessels in the human body. PC MRA need to at least four images for angiogram reconstruction and it caused longer scan time. Therefore, we used keyhole imaging combined PC MRA to reduce the scan time. However, keyhole imaging can lead the erroneous effects as loss of phase information or frequency discontinuous. In this study, we applied the keyhole imaging combined 2D PC MRA for improving the temporal resolution and also measured the velocity to evaluate the accuracy of phase information. We used 0.32T MRI scanner(Magfinder II, Scimedix, Korea). Using the 2D PC MRA pulse sequence, the vascular images for a human brain targeted on the Superior Sagittal Sinus(SSS) were obtained. We applied tukey window function for keyhole images to minimize the ringing artifact and erroneous factors that are induced frequency discontinuous and phase information loss. We also applied zero-padded algorithm to peripheral missing k-space lines to compare keyhole imaging results and the artifact power(AP) value was measured on the complex difference images to validate the image quality. Consider as based on our results, heavy image distortions and artifacts were shown until using at least 50% keyhole factor. Using above the 50% keyhole factors are shown well reconstructed and matched for magnitude images and velocity information measurements. In conclusion, we confirmed the image quality and velocity information of keyhole technique combined 2D PC MRA. Especially, measured velocity information through the keyhole imaging combination was similar to the velocity information of full sampled k-space image despite of frequency discontinuous and phase information loss in the keyhole imaging reconstruction process. Consequently, the keyhole imaging combined 2D PC MRA will give some clinical usefulness and advantages as improving the temporal resolution and measuring the velocity information via selecting the appropriate keyhole factor at low tesla MRI system.

• Composites Research
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• v.13 no.1
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• pp.1-10
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• 2000

During the compression molding process of the continuous fiber-reinforced polymeric composites, two main problems such as fiber-matrix separation and fiber orientation are produced by the difference of flow velocity. Molded parts are lead to be nonhomogeneous and anisotropic. As the mechanical property of the products are dependent on the separation and orientation, it is important to research the fiber mat structure and molding condition. If the fiber mat structure is changed by the increment of needling, the separation decreases and after compression molding the orientation is easily aligned. As it were, the compression moldability is good. But the defects as tears, thin thickness are produced in the products. Therefore, it is important to clarify the moldability in relation to the usage of products and the expenses of produce on the actual process. Therefore we must make the measurement methods that can define the moldability of products. In this research, the effects of the fiber mat structure(NP = 0, 5, 10, 25, 50 punches/$cm^2$) and the mold geometry($r_p$ = 1, 25, 50 mm) on the moldability of products were discussed. We investigated the case of one-dimensional flow in order to obtain the degree of nonhomogeneity and the fiber orientation function. In result, we could gain the correlation coefficient of the continuous fiber-reinforced polymeric composites. Also we experimented on the cup-type compression molding which was appeared the wrinkle on the flange part by the complex stress condition in order to gain the degree of nonhomogeneity and area ratio. In result, the moldability of products was expressed as the correlation coefficient and area ratio.

• Applied Microscopy
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• v.17 no.1
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• pp.83-97
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• 1987

In order to discriminate the enteroendocrine cell types in the mucosal epithelium of the normal duodenum of the Korean hedgehog (Erinaceus koreanus). The tissues were fixed in the mixture of 1% paraformaldehyde and 1% glutaraldehyde in phosphate buffer (pH 7.2), and postfixed in 2% osmium tetroxide (phosphate buffer, pH 7.2). They were embedded in Araldite, and the ultrathin sections were made by LKB-V ultratome following the inspection of semithin sections stained with toluidine blue-borax solutions. Ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100B electron microscope. At least six types of enteroendocrine cells distributed in the mucosal epithelium of the duodenum were identified according to their morphological characteristics mainly based on the size, shape, number and electron density of the secretory granules. Type I cells had moderately developed organelles. The secretory granules were pleomorphic ($370X510nm$), and the granule cores with high electron density were enveloped in limiting membrane and characterized by a narrow halo. Type II cells contained an indented nucleus and well-developed organelles. The secretory granules were round (350 nm) and classified in two kinds by electron density, moderate and high. Both granules were surrounded by limiting membrane and those with high electron density showed often a wide halo. Type III cells had an indented nucleus. The secretory granules with various electron density were round (220 nm) in shape. The granules with high electron density were enveloped in limiting membrane and characterized by a narrow halo, but those with low or moderate electron density had not been observed the limiting membrane. Type IV cells contained an indented nucleus and moderately developed organelles. The secretory granules were round (180 nm) in shape, and the granule cores with high electron density were enveloped in limiting membrane and showed often a wide halo. Type V cells had a large amount of rough endoplasmic reticulum. Secretory granules with low or moderate electron density were round (230 nm) in shape, and surrounded by limiting membrane and showed a narrow halo. Type VI cells contained an oval nucleus and well-developed organelles, especially Golgi complex. The secretory granules with high electron density were round (210 nm) in shape. The granules were enveloped in limiting membrane and showed often a wide halo.

• Applied Microscopy
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• v.27 no.1
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• pp.13-30
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• 1997

The experiment was performed to study the morphological responses of the thymus of the mice, to antitumour agents (5-Fluorouracil or mitomycin C). Healthy adult mice weighing 25 gm each were divided into normal and experimental groups. 5-Fluorouracil (60 mg/kg) or Mitomycin-C $(400{\mu}g/kg)$ were injected subcutaneously to the animals every other day. Animals were sacrificed at 4 days and 7 days following the first injection. Pieces of the tissue taken from the thymus were prefixed with 2.5% paraformaldehyde-l.5% glutaraldehyde, followed by post-fixation with 1% osmium tetroxide. Ultrathin sections stained with uranyl acetate and lead citrate were observed with a JEM 100 CX-II electron microscope. The observed results were as follow: 1. Apoptoses of T-lymphocytes were observed more frequently in the thymus of the experimental groups than in those of a normal group. 2. In the experimental group, the plasma cells with distended cisternae of the granular endoplasmic reticulum and the eosinophile leukocytes were observed frequently. 3. In the experimental group, newly forming Hassall's corpurscles were observed frequently. 4. In the mitomycin-treated group, the epithelial reticular cells containing distended perinuclear cisternae, distended the granular endoplasmic reticula and pyknotic nuclei were observed in the cortico-medullary junctional area. 5. In the mitomycin-treated group, nuclear bodies with medium electron dense materials were often observed in the T lymphocyte. 6. In the 5-fluorouracil-treated groups, fused and dissolved tonofilament bundles and apoptotic bodies were observed in the some epithelial reticular cells in the medullary area. 7. In the 5-fluorouracil-treated groups, some elongated and bar-shaped lysosomes with electron lucent gap were often observed in the macrophages. 8. In the 5-fluorouracil-treated group, membrane complex of the smooth endoplasmic reticulum were ofen observed in the macrophage. From the above results, it was suggested that 5-fluorouracil or mitomycin could induce rapid involution of the thymus, and disturb maturation and differentiation of T lymphocytes, and, in turn, supress immunity.

• Economic and Environmental Geology
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• v.25 no.4
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• pp.417-433
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• 1992

Lead-zinc-copper deposits of the Jeonheung and the Oksan mines around Euiseong area occur as hydrothermal quartz and calcite veins that crosscut Cretaceous sedimentary rocks of the Gyeongsang Basin. The mineralization occurred in three distinct stages (I, II, and III): (I) quartz-sulfides-sulfosalts-hematite mineralization stage; (II) barren quartz-fluorite stage; and (III) barren calcite stage. Stage I ore minerals comprise pyrite, chalcopyrite, sphalerite, galena and Pb-Ag-Bi-Sb sulfosalts. Mineralogies of the two mines are different, and arsenopyrite, pyrrhotite, tetrahedrite and iron-rich (up to 21 mole % FeS) sphalerite are restricted to the Oksan mine. A K-Ar radiometric dating for sericite indicates that the Pb-Zn-Cu deposits of the Euiseong area were formed during late Cretaceous age ($62.3{\pm}2.8Ma$), likely associated with a subvolcanic activity related to the volcanic complex in the nearby Geumseongsan Caldera and the ubiquitous felsite dykes. Stage I mineralization occurred at temperatures between > $380^{\circ}C$ and $240^{\circ}C$ from fluids with salinities between 6.3 and 0.7 equiv. wt. % NaCl. The chalcopyrite deposition occurred mostly at higher temperatures of > $300^{\circ}C$. Fluid inclusion data indicate that the Pb-Zn-Cu ore mineralization resulted from a complex history of boiling, cooling and dilution of ore fluids. The mineralization at Jeonheung resulted mainly from cooling and dilution by an influx of cooler meteoric waters, whereas the mineralization at Oksan was largely due to fluid boiling. Evidence of fluid boiling suggests that pressures decreased from about 210 bars to 80 bars. This corresponds to a depth of about 900 m in a hydrothermal system that changed from lithostatic (closed) toward hydrostatic (open) conditions. Sulfur isotope compositions of sulfide minerals (${\delta}^{34}S=2.9{\sim}9.6$ per mil) indicate that the ${\delta}^{34}S_{{\Sigma}S}$ value of ore fluids was ${\approx}8.6$ per mil. This ${\delta}^{34}S_{{\Sigma}S}$ value is likely consistent with an igneous sulfur mixed with sulfates (?) in surrounding sedimentary rocks. Measured and calculated hydrogen and oxygen isotope values of ore-forming fluids suggest meteoric water dominance, approaching unexchanged meteoric water values. Equilibrium thermodynamic interpretation indicates that the temperature versus $fs_2$ variation of stage I ore fluids differed between the two mines as follows: the $fs_2$ of ore fluids at Jeonheung changed with decreasing temperature constantly near the pyrite-hematite-magnetite sulfidation curve, whereas those at Oksan changed from the pyrite-pyrrhotite sulfidation state towards the pyrite-hematite-magnetite state. The shift in minerals precipitated during stage I also reflects a concomitant $fo_2$ increase, probably due to mixing of ore fluids with cooler, more oxidizing meteoric waters. Thermodynamic consideration of copper solubility suggests that the ore-forming fluids cooled through boiling at Oksan and mixing with less-evolved meteoric waters at Jeonheung, and that this cooling was the main cause of copper deposition through destabilization of copper chloride complexes.

• The Korean Journal of Pharmacology
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• v.19 no.1
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• pp.15-35
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• 1983

Although it has been well known that ventricular fibrillation is the most important complication during hypothermia, much investigation has failed to show the exact nature of the etiology of ventricular fibrillation. Recently, there has been considerable research on the relationship between sympathetic activity and ventricular fibrillation under hypothermia. Cardiac muscle normally contains a certain amount of norepinephrine and the dramatic effect of this catecholamines on the cardiac muscle is well documented. It is, therefore, conceivable that cardiac catecholamines might exert an influence on the susceptibility of heart muscle to tachycardia, ventricular fibrillation and arrhythmia, under hypothermia. Hypothermia itself is stress enough to increase tonus of sympatheticoadrenal system. The normal heart is supplied by an autonomic innervation and is subjected to action of circulating catecholamines which may be released from the heart. If the reaction of the heart associated with a variable amount of cardiac catecholamines is. permitted to occur in the induction of hypothermia, the action of this agent on the heart has not to be differentiated from the direct effects of cooling. The studies presented in this paper were designed to provide further information about the cardio-physiological effects of reduced body temperature, with special reference to the role of catecholamines in ventricular fibrillation. Healthy cats, weighing about 3 kg, were anesthetized with pentobarbital(30 mg/kg) intraperitoneally. The trachea was intubated and the endotracheal tube was connected to a C.F. Palmer type A.C. respirator. Hypothermia was induced by immersing the cat into a ice water tub and the rate of body temperature lowering was $1^{\circ}C$ per 5 to 8 min. Esophageal temperature and ECG (Lead II) were simultaneously monitored. In some cases the blood pH and serum sodium and potassium were estimated before the experiment. After the experiment the animals were killed and the hearts were excised. The catecholamines content of the cardiac muscle was measured by the method of Shore and Olin (1958). The results obtained are summarized as follows. 1) In control animal the heart rate was slowed as the temperature fell and the average pulse rates of eight animals were read 94/min at $31^{\circ}C$, 70/min at $27^{\circ}C$ and 43/min at $23^{\circ}C$ if esophageal temperature. Ventricular fibrillation was occurred with no exception at a mean temperature of $20.3^{\circ}C(21-l9^{\circ}C)$. The electrocardiogram revealed abnormal P waves in each progressive cooling of the heart. there was, ultimately, a marked delay in the P-R interval, QRS complex and Q-T interval. Inversion of the T waves was characteristic of all animals. The catecholamines content of the heart muscle excised immediately after the occurrence of ventricular fibrillation was about thirty percent lower than that of the pre-hypothermic heart, that is, $1.0\;{\mu}g/g$ wet weight compared to the prehypothermic value of $1.41\;{\mu}g/g$ wet weight. The changes of blood pH, serum sodium and potassium concentration were not remarkable. 2) By the adrenergic receptor blocking agent, DCI(2-3 mg/kg), given intramuscularly thirty minutes before hypothermia, ventricular fibrillation did not occur in one of five animals when their body temperature was reduced even to $16^{\circ}C$. These animals succumbed at that low temperature, and the changes of heart rate and loss of myocardial catecholamines after hypothermia were similar to those of normal animals. The actual effect of DCI preventing the ventricular fibrillation is not predictable. 3) Administration of reserpine(1 mg/kg, i.m.) 24 hours Prior to hypothermia disclosed reduced incidence of ventricular fibrillation, that is, six of the nine animals went into fibrillation at an average temperature of $19.6^{\circ}C$. By reserpine myocardial catecholamines content dropped to $0.045\;{\mu}g/g$ wet weight. 4) Bretylium pretreatment(20 mg/kg, i.m.), which blocks the release of catecholamines, Prevented the ventricular fibrillation under hypothermia in four of the eight cats. The pulse rate, however, was approximately the same as control and in some cases was rather slower. 5) Six cats treated with norepinephrine(2 mg/kg, i.m.) or DOPA(50 mg/kg) and tranylcypromine(10 mg/kg), which tab teen proved to cause significant increase in the catecholamines content of the heart muscle, showed ventricular fibrillation in all animals under hypothermia at average temperature of $21.6^{\circ}C$ and the pulse rate increased remarkably as compared with that of normal. Catecholamines content of cardiac muscle of these animals markedly decreased after hypothermia but higher than control animals. 6) The functional refractory periods of isolated rabbit atria, determined by the paired stimulus technique, was markedly shortened by administration of epinephrine, norepinephrine and isoproterenol. 7) Adrenergic beta-blocking agents, such as pronethalol, propranolol and sotalol(MJ-1999), inhibited completely the shortening of refractory period induced by norepinephrine. 8) Pretreatment with either phenoxftenbamine or phentolamine, an adrenergic alphatlocking agent, did not modify the decrease in refractory period induced by norepinephrine. From the above experiment it is possible to conclude that catecholamines play an important role in producing ventricular fibrillation under hypothermia. The shortening of the refractorf period of cardiac muscle induced by catecholamines mar be considered as a partial factor in producing ventriculr fibrillaton and to be mediated by beta-adrenergic receptor.

• Journal of the Korean Chemical Society
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• v.44 no.5
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• pp.403-409
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• 2000

The formation and dissociation rates of $Zn^{2+}$ Complexes with l,4,7,10-tetraaza-13,16-diox-acyclooctadecane-N,N',N",N'"-tetraacetic acid (1), 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetramethylacetic acid (2), and 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetrapropionic acid(3) have been measured by stopped-flow and conventional spectrophotometry. Observations were made at 25.0$\pm$0.1 $^{\circ}C$ and at an ionic strength of 0.10 M NaClO$_4$. The formation reactions of $Zn^{2+}$ ion with 1 and 2 took place by the rapid formation of an intermediate complex (ZnH$_3L^+$) in which the $Zn^{2+}$ ion is incompletely coor-dinated. This might then lead to be a final product in the rate-determining step.ln the pH range 4.76-5.76, the diprotonated (H2L2-) form is the kinetically active species despite of its low concentration. The stability con-stants (log$K_{(ZnH$_3$3$L^+$)}$) and specific water-assisted rate constants (koH) of intermediate complexes have been deter-mined from the kinetic data. The dissociation reactions of $Zn^{2+}$ complexes of 1,2, and 3 were investigated with $Cu^{2+}$ ions as a scavenger in acetate buffer. All complexes exhibit acid-independent and acid-catalyzed con-tributions. The effect of buffer and $Cu^{2+}$ concentration on the dissociation rate has also been investigated. The ligand effect on t dissociation rate of $Zn^{2+}$ complexes is discussed in terms of the side-pendant armsand the chelate ring sizes of the ligands.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.2
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• pp.95-106
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• 2007

Objective: We previously identified differentially expressed genes (DEGs) between germinal vesicle (GV) and metaphase II (MII) mouse oocyte. The present study was accomplished as a preliminary study to elucidate the role of ribose 5-phosphate isomerase A (Rpia), the essential enzyme of the pentose phosphate pathway (PPP), in oocyte maturation. We observed expression of Rpia in the mouse and porcine oocytes. Methods: Expression pattern of the 11 MII-selective DEGs in various tissues was evaluated using RT-PCR and selected 4 genes highly expressed in the ovary. According to the oocyte-selective expression profile, we selected Rpia as a target for this study. We identified the porcine Rpia sequence using EST clustering technique, since it is not yet registered in public databases. Results: The extended porcine Rpia nucleotide sequence was submitted and registered to GenBank (accession number EF213106). We prepared primers for porcine Rpia according to this sequence. In contrast to the oocyte-specific expression in the mouse, Rpia was expressed in porcine cumulus and granulosa cells as well as in oocytes. Conclusion: This is the first report on the characterization of the Rpia gene in the mouse and porcine ovarian cells. Results of the present study suggest that the mouse and porcine COCs employ different mechanism of glucose metabolism. Therefore, the different metabolic pathways during in vitro oocyte maturation (IVM) in different species may lead different maturation rates. It is required to study further regarding the role of Rpia in glucose metabolism of oocytes and follicular cell fore exploring the regulatory mechanism of oocyte maturation as well as for finding the finest culture conditions for in vitro maturation.