• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.457-461
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• 1998

The vesicle system of DPPC(dipalmitoylphosphaticylcholine)/Chol(Cholesterol) has been modified by incorporating various mole fractions of flourinated surfactant($C_8F_{17}(CH_2)_2OCO-CH_2CH(SO_3Na)COO(CH_2)_2C_8F_{17}$. Sodium bis(1H,1H,2H,2H-heptadecaflurododecyl)-2-sulfosuccinate, FS)/fluorinated fatty acid salt ($C_7F_{15}COONH_4$, ammoniumpentadecaflurooctyrate, FFS), and their physicochemical properties have been investigated in an attempt to enhance the stability of phospholipid vesicle system. The ${\zeta}$-potential measurement by use of Zetamaster sub-micron Particle Electrophoresis Analyzer (Malvern Co.) showed that a charged homogeneous DPPC/Chol/FS vesicle has been formed owing to the incorporated FFS effect on the membrane, playing a role as a cosurfactant in the bilayer between DPPC and FS components. With increase in the concentration of FFS, it was found that the particle size and also surface charge of the DPPC/Chol/FS vesicle decreased. The stability of DPPC/Chol/FS/FFS liposome was found to be enhanced significantly compared to that of DPPC/Chol/FS according to the dispersity change as a function of time. The release rate of dye molecule of Methylene Blue from the DPPC/Chol/FS/FFS vesicle was determined to be slower than that of DPPC/Chol/FS system, and it may be attributed to the increase in microviscosity of the hydrophobic region in the bilayer. The affinfinity of DPPC/Chol/FS/FFS vesicles to albumin was found to be slightly lowered compared to that of DPPC/Chol/FS. Based on these findings, it was confirmed that a more stable and homogeneous vesicle system of DPPC/Chol/FS could be prepared by addition of FFS, acting as a cosurfactant in the aggregate formation.

• Journal of Periodontal and Implant Science
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• v.33 no.3
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• pp.457-474
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• 2003

The ultimate objective of periodontal treatment is to get rid of an on-going periodontal disease and further regenerate the supporting tissue, which is already destroyed, functionally. Currently, the bone grafting operation using various kinds of bone grafting materials and the operation for induced regeneration of periodontal tissue using the blocking membrane are performed for regeneration of the destroyed periodontal tissue. However, there are respective limitations Galenical preparations, which are used for regeneration of periodontal of tissue, has less risk of rejective reaction or toxicity that may be incidental to degradation and their effect is sustainable. Thus, in case they are applicable to a clinic, they can he used economically. Chitosan has such compatibility, biological actions including antibacterial activity, acceleration of wound treatment, etc., and excellent mechanical characteristics, which has recently aroused more interest in it. Also, it has been reported that it promotes osteogenesis directly or indirectly by functioning as a matrix to promote migration and differentiation of a specific precussor cell (for example, osteoblast) and further inhibiting the function of such a cell as fibroblast to prevent osteogenesis. In this study, the pure chitosan solution, which was obtained by purifying chitosan, was used. However, since this chitosan is of a liquiform, it is difficult to sustain it in a defective region. It is, therefore, essential to use a carrier for delivering chitosan to, and sustaining it gradually in the defective region. In the calvarial defect model of the Sprague-Dawley rat, it is relatively easy to maintain a space. Therefore, in this study, the chitosan solution with which ACS was wetted was grafted onto the defective region, For an experimental model, a calvarial defect of rat m s selected, and a critical size of the defective region was a circular defect with a diameter of 8 mm. A group in which no treatment was conducted for the calvarial defect was set as a negative control group. Another group in which treatment was conducted with ACS only was set as a positive control group (ACS group). And another group in which treatment was conducted was conducted with by grafting the pure chitosan solution onto the defective region through ACS which was wetted with the chitosan solution was set an experimental group (Chitosan/ACS group). Chitosan was applied to the Sprague-Dawley rat's calvarial bone by applying ACS which was wetted with the chitosan solution, and each Sprague-Dawley rat was sacrificed respectively 2 weeks and 8 weeks after the operation for such application. Then, the treatment results were compared and observed histologically and his tometrically. Thereby, the following conclusions were obtained. 1. In the experimental group, a pattern was shown that from 2 weeks after the operation, vascular proliferation proceeded and osteogenesis proceeded through osteoblast infiltration, and at 8 week after the operation, ACS was almost absorbed, the amount of osteogensis was increased and many osteoid tissue layers were observed. 2. At 2 weeks after the operation, each amount of osteogenesis appeared to be 8.70.8 %, 13.62.3 % and 4.80.7 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be higher in the Experimental group and the positive control group than in the negative control group, but there was no significant difference statistically (p<0.01). 3. At 8 weeks after the operation, each amount of osteogenesis appeared to be 62.26.1%, 17.42.5 % and 8.21.4 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be substantially higher in the experimental group than in the positive control group and the negative control group, and there was a significant difference statistically (p<0.01). As a result of conducting the experiment, when ACS was used as a carrier for chitosan, chitosan showed effective osteogenesis in the perforated defective region of the Sprague-Dawley rat's calvarial bone.

• Journal of Life Science
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• v.26 no.11
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• pp.1232-1236
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• 2016

Mitochondrial calcium uptake 1 (MICU1) including two canonical EF hands, located in the mitochondrial inner membrane, is known to play a crucial role in the calcium uptake in mitochondria. Mitochondrial calcium uptake in muscular cells is related to post mortem shortening by calcium release from muscles. Therefore, the porcine MICU1 gene has been estimated as a genetic candidate for meat quality traits. In this study, variations on the exonic regions of the porcine MICU1 gene were investigated by sequencing cDNAs and tested for their association with meat quality traits. A total of 667 Berkshire heads (347 sows and 320 castrated boars) were used for this association test. Three SNPs were detected on the 3' untranslated region (UTR) of the porcine MICU1 gene. SNP1 (c.*136G>A) was associated with drip loss (p=0.017) and intramuscular fat content (p=0.039). In addition, SNP2 (c.*222G>A) and SNP3 (c.*485G>A) were associated with drip loss (p=0.018) and intramuscular fat content (p<0.001), respectively. In conclusion, it was verified that three variations on the 3' UTR of the porcine MICU1 gene were significantly associated with meat quality traits. It was also suggested that molecular biological analyses are needed to validate the function of variations on the 3 UTR of the porcine MICU1 gene.

• Childhood Kidney Diseases
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• v.8 no.2
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• pp.166-175
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• 2004

Purpose: Present study has been undertaken to determine the distribution of various renal diseases causing asymptomatic hematuria in children and to evaluate the benefit of doing renal biopsy in these children. Methods: Study population consisted of 146 children with asymptomatic primary hematuria who had been admitted to the pediatric departmen of Kyungpook National University Hospital for the past 4 years from 1999 to 2002. In 122 out of 146 cases, renal biopsy was performed percutaneously and in 24 out of 146 cases, diagnosed as idiopathic hypercalciuria, oral calcium loading test was performed. Results: The age$(mean{\pm}SD)$ at onset or discovery of hematuria of the 146 children in-cluded in this study was $8.0\pm3.2$ years and the proportion of boys and girls was 54.8% and 45.2%, respectively. In 76 out of 146 cases(52%), asymptomatic hematuria was first diagnosed by school urinalysis screening. The proportion of histopathologic findings based on 122 biopsies was as follows : Thin Glomerular Basement Membrane(TGBM) 73 cases(50%): IgA nephropathy 20 cases(14%): Alport syndrome 6 cases(4%), Membranous Glomerulonephropathy(MGN) 4 cases(3%): Membranoproliferative Glomerulonephritis(MPGN) 2 cases(1%); IgA nephropathy with TGBM 3 cases(2%): 'normal' glomeruli 14 cases(10%) Twenty four cases (16%) were diagnosed as idiopathic hypercalciuria. During follow-up periods, 15% of 146 cases became hematuria-free and renal function did not deteriorate in any cases. Conclusion: Unless hematuric children manifest poor prognostic indicators for renal survival, we would recommend long term regular follow-up prior to a renal biopsy.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.152-157
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• 1997

From August 1986 until June 1995, single aortic valve replacement was performed in 65 patients at the Chonnam National University Hospital. worthy-eight were male and 17 were female patients, ranging from 19 to 68 years of age(median : 43 years). The causes of the valve lesions were rheumatic in 29 patients (44.6%), bicuspid aortic valve in 6 patients (6.2%), endocarditis in 6 patients(6.2%), unknown in others. Concomitant surgical procedures were performed in 10 patients : repair of congenital defect in 5, pericardiectomy in 1, coronary artery bypass grafting in 1, noncoronary sinus plication in 1, Valsalva sinus aneurysmectomy in 1, subaortic membrane resection in 1 Used valves were 51. Jude-Medical valve in 42, Duromedics valve in 22, Bjork-Shiley valve in 2, Carpentier-Edward valve in 1. There were 3 hospital deaths (4.6%), and 2 late deaths (3.2%). Follow-up was 95.2% complete. The 10-year acturlal survival rate was 85.3%. Postoperative complications were low cardiac utput in 8, arrythmia in 5, valve related hemolysis in 1, cerebral infarction in 1, and gastrointestinal bleeding in 2. Reoperation was performed in 4 for surgical bleeding, in 3 for paravalvular leak. The mean improvement in New York Heart Association functional class is from 2.79 $\pm$ 0.66 preoperatively to 1.25 $\pm$ 0.49 postoperatively(p < 0.001) The change of cardiothoracic ratio from preoperative to postoperative is 0.57 $\pm$ 0.06 to 0.54 $\pm$ 0.05 (p < 0.05). The left ventricular ejection fraction change is not significant perioperatively. There are no mechanical failures. This early and intermediate-term follow-up suggests that in adults in whom valve repair is not possible, the mechanical valve is a reliable and durable prosthesis with good hemodynamic function and a low rate of thromboembolic event.

• Journal of Korean Medical classics
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• v.12 no.2
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• pp.56-71
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• 1999

1. In the recohnition of cosmos true form, It is compared to the Boundless(無極) the Great Absolute(太極),Yin and Yang(兩儀) throungh the fertilazation process of spermatozoon and ovum. 2. It is explained that principle of unchange through the Form and Action(體 用) relation of the outer appearances and Number (象數) with matching the number of nine and ten to HaDoo(河圖) and RakSye(洛書). 3. Eigth divinations(八卦) being compared to the human body, Care presevation of pregnancy(養胎) is explained that head forms firstly(Gun-I 1乾一), secondly lung(Tae-E 兌二), heart(E-Sam 離三), liver(Jin-Sa 震四), gall bladder(Son-Oo 巽五), kidney(Gam-Yuk 坎六), intestines and stomach(Gan-Chill 艮七), lastly flesh forms(Gon-Pal 坤八). 4. It is explained that process of physiological change of $\ll$Nei Ching The Natural Truth in Ancient Times$\gg$(內經 上古天眞論) by matching boy at the age of 8 to Gan-divination(艮卦), and girl at the age of 7 to Tae-divination(兌卦). 5. The theory of six sons from Gun-Gon(乾坤六子論) is explained by relation of Apriority Eight-divination(先天八卦) obedience and disobedience-left and right. 6. It is explained that form of the human-body and the relationship of the Heart - the Kidney through the Gam(坎) Li(離) - divination 7. The effort of interpretating time and space of the Twelve Horary signs is explanined by season, direction, Five elements(五行), rise and decline, the Three Sum(三合), the Six Sum (六合), the six crash(六衡)'s relation. 8. the process of change from apriority(先天) to postery(後天) in the book of Changes(周易) is explanined by comparing to the phenomenum of nature and the human body. 9. The Energy Satus(氣位) are different from the direction of Eight-divination(八卦) and the properties of the good or bad of herb-drugs are differnt from the place of production. 10. The rightness of realizating the Overlapping-divinations(重卦) are compared to the phenomenum of nature through the Divination Virture(卦德). 11. The dependence-relations of The Twelve Meridians(十二經脈) are explained by-matching January with liver meridian, February with gall bladder meridian, march with heart pericardium meridiam, April with small intestine meridkan, August with lung spleen meridian, jury with stomach meridian, August with lung meridian, September with large intestine meridian, October with urinary bladder meridianm November with kidney meridian. December with triple energizer meridian throng The Twelve Byuk-divination. 12. The process of menstration cycle is explained by The Month symbolizing-divination(月候卦). 13. Through The Trade(交易) prove the reason of feverish sympotoms to use feverish Drug, mill sympotoms to use mill drug of prescription and Heart-Kidneys Consensus(心賢相交) and through The Change(變易), prove the chill and feverish consensus of forechill after feverish, fore feverish after chill and through. The Non-Change(不易) explain the reason of chill sympotoms to use feverish drug, feverish sympotoms to use chill drug of prscription. 14. Ho-divination(互卦) applicate Jxa Sa(佐使) herb drug match of Kun Sin Jwa Sa() theory. 15. According to the Hyo-position(爻位) match the ages, body form and drug by matching Ehight-divination(八卦) to the human body form and function in medicine and the book of Changes(周易) application emphasize the human body Ehight-divination(人身八卦). 16. Throgh the Order-divination(序卦) explain the rightness of Divination Image(卦象) arrangement and all things take shape by cosmo-energy conseusus(宇宙氣交). 17. Throgh the Mixing-divination(難卦) supply the vacancy of medicine and the book of Changes(周易) relationship in the foreword explian the human energy movements, sleep, vomitting, the energy arrival(逮氣), heart pericardium(心包), lung membrane(肺膜) etc.... Like the above sentence medicine and the book of Changes(周易) theory of scholar Tang on the viewpoint of easten-the way Western appliance(東道西器) researching abyss of medicine impart to descendants, so I think that the achievement of medicine and the book of Changes(周易) study is very excellant and I expect that the study Korean Oriental Medicine(韓醫學) theory by means of medicine the book of Changes(周易) reference, will be accelarated.

• The Korean Journal of Malacology
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• v.24 no.1
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• pp.41-50
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• 2008

The histochemical characteristics and ultrastructure of the mantle in the spiny top shell, Batillus cornutus were described using light and electron microscopy. The simple epidermal layer wrapped on the top and bottom of the centrally located connective tissue. And then the epidermal layer were divided into the outer epidermal layer near a shell and the inner epidermal layer closed to the visceral mass. The connective tissue layer was composed of the collagen fiber muscularfiber bundle and hemolymph sinus. Mucous cells in the apical mantle contained acid and neutral mucopolysaccaride, and acidic carboxylated mucopolysaccaride in the mid and marginal mantle. The mantle thickness, epidermal layer thickness and hemolymph sinus area displayed a trend of reduction from the marginal zone to the apical zone. From TEM observation, it was possible to distinguish epithelium, ciliated cell, absorptive cell and secretory cell in the epidermal layer. The epithelia were columnar and the nucleus was elliptical. The free surface were covered with microvilli. The lateral membranes of epithelium was con nected with neighboring cells by the zonular occludens, zonular adherens and membrane interdigitation. Ciliated cell on free surface had cilia and microvilli, and numerous mitochondria in the apical cytoplasm. In the epidermal layer, it observed 2 type cells having absorptive function. The absorptive cells were columnar in shape, and contained microvilli, pinocytotic vesicles, mitochondria and lysosomes of various electron density. Secretory cells can be divided into four types (A, B, C, D) depending on the cell shape and characteristics of secretory granules. These cells were unicellular glands and had similar characteristics to previously reported on the mantle of the gastropod and bivalves.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.273-289
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• 1994

Reversible brain ischemia was produced by occluding both common carotid arteries for 5 min, and the effects of aminoguanidine (AG), $DL-{\alpha}-difluoromethylornithine$ (DFMO), MK-801, and nimodipine (NM) on the ischemia induced changes of the polyamine, glutamate and acetylcholine levels in the hippocampus CA1 subfield and the specific $[^3H]\;MK-801$ binding to the hippocampus synaptosomal membranes were studied with a histological reference of the cresyl violet stained hippocampus. The basal putrescine level $(PT:\;74.4{\pm}8.8\;nM)$ showed a rapid increase (up to 1.7 fold) for 5 min of ischemia, remained significantly increased for 6 h, and then resumed the further increase to amount gradually up to about 3 fold 96 h after recirculation. However, the level of spermidine was little changed, and the spermine level showed a transient increase during ischemia followed by a sustained decrease to about 40% of the preischemic level after recirculation. The increase of PT level induced by brain ischemia was enhanced with AG or MK-801, but it was reduced by DFMO or NM. The basal glutamate level $(GT:\;0.90{\pm}0.l4\;{\mu}M)$ rapidly increased to a peak level of $8.19{\pm}1.14\;{\mu}M$ within 5 min after onset of the ischemia and then decreased to the preischemic level in about 25 min after recirculation. And NM reduced the ischemia induced increase of GT level by about 25%, but AG, DFMO and MK-801 did not affect the GT increase. The basal acetylcholine level $(ACh:\;118.0{\pm}10.5\;{\mu}M)$ did little change during/after brain ischemia and was little affected by AG or NM. But DFMO and MK-801, respectively, produced the moderate decrease of ACh level. The specific $[^3H]\;MK-801$ binding to the hippocampus synaptosomal membrane was little affected by brain ischemia for 5 min. The control value (78.9 fmole/mg protein) was moderately decreased by AG and MK-801, respectively but was little changed by DFMO or NM. The microscopic findings of the brains extirpated on day 7 after ischemia showed severe neuronal damage of the hippocampus, particularly CA1 subfield. NM and AG moderately attenuated the delayed neuronal damage, and DFMO, on the contrary, aggravated the ischemia induced damage. However, MK-801 did not protect the hippocampus from ischemic damage. These results suggest that unlike to the mode of anti-ischemic action of NM, AG might protect the hippocampus from ischemic injury as being negatively regulatory on the N-methyl-D-aspartate (NMDA) receptor function in the hippocampus.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.27-47
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• 1992

Engineers have developed new instruments that aid in diagnosis and therapy Ultrasonic imaging has provided a nondamaging method of imaging internal organs. A complex transducer emits ultrasonic waves at many angles and reconstructs a map of internal anatomy and also velocities of blood in vessels. Fast computed tomography permits reconstruction of the 3-dimensional anatomy and perfusion of the heart at 20-Hz rates. Positron emission tomography uses certain isotopes that produce positrons that react with electrons to simultaneously emit two gamma rays in opposite directions. It locates the region of origin by using a ring of discrete scintillation detectors, each in electronic coincidence with an opposing detector. In magnetic resonance imaging, the patient is placed in a very strong magnetic field. The precessing of the hydrogen atoms is perturbed by an interrogating field to yield two-dimensional images of soft tissue having exceptional clarity. As an alternative to radiology image processing, film archiving, and retrieval, picture archiving and communication systems (PACS) are being implemented. Images from computed radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound are digitized, transmitted, and stored in computers for retrieval at distributed work stations. In electrical impedance tomography, electrodes are placed around the thorax. 50-kHz current is injected between two electrodes and voltages are measured on all other electrodes. A computer processes the data to yield an image of the resistivity of a 2-dimensional slice of the thorax. During fetal monitoring, a corkscrew electrode is screwed into the fetal scalp to measure the fetal electrocardiogram. Correlations with uterine contractions yield information on the status of the fetus during delivery To measure cardiac output by thermodilution, cold saline is injected into the right atrium. A thermistor in the right pulmonary artery yields temperature measurements, from which we can calculate cardiac output. In impedance cardiography, we measure the changes in electrical impedance as the heart ejects blood into the arteries. Motion artifacts are large, so signal averaging is useful during monitoring. An intraarterial blood gas monitoring system permits monitoring in real time. Light is sent down optical fibers inserted into the radial artery, where it is absorbed by dyes, which reemit the light at a different wavelength. The emitted light travels up optical fibers where an external instrument determines O2, CO2, and pH. Therapeutic devices include the electrosurgical unit. A high-frequency electric arc is drawn between the knife and the tissue. The arc cuts and the heat coagulates, thus preventing blood loss. Hyperthermia has demonstrated antitumor effects in patients in whom all conventional modes of therapy have failed. Methods of raising tumor temperature include focused ultrasound, radio-frequency power through needles, or microwaves. When the heart stops pumping, we use the defibrillator to restore normal pumping. A brief, high-current pulse through the heart synchronizes all cardiac fibers to restore normal rhythm. When the cardiac rhythm is too slow, we implant the cardiac pacemaker. An electrode within the heart stimulates the cardiac muscle to contract at the normal rate. When the cardiac valves are narrowed or leak, we implant an artificial valve. Silicone rubber and Teflon are used for biocompatibility. Artificial hearts powered by pneumatic hoses have been implanted in humans. However, the quality of life gradually degrades, and death ensues. When kidney stones develop, lithotripsy is used. A spark creates a pressure wave, which is focused on the stone and fragments it. The pieces pass out normally. When kidneys fail, the blood is cleansed during hemodialysis. Urea passes through a porous membrane to a dialysate bath to lower its concentration in the blood. The blind are able to read by scanning the Optacon with their fingertips. A camera scans letters and converts them to an array of vibrating pins. The deaf are able to hear using a cochlear implant. A microphone detects sound and divides it into frequency bands. 22 electrodes within the cochlea stimulate the acoustic the acoustic nerve to provide sound patterns. For those who have lost muscle function in the limbs, researchers are implanting electrodes to stimulate the muscle. Sensors in the legs and arms feed back signals to a computer that coordinates the stimulators to provide limb motion. For those with high spinal cord injury, a puff and sip switch can control a computer and permit the disabled person operate the computer and communicate with the outside world.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.261-270
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• 1992

Many herbicides that are applied at the soil before weed emergence inhibit plant growth soon after weed germination occurs. Plant growth has been known as an irreversible increase in size as a result of the processes of cell divison and cell enlargement. Herbicides can influence primary growth in which most new plant tissues emerges from meristmatic region by affecting either or both of these processes. Herbicides which have sites of action during interphase($G_1$, S, $G_2$) of cell cycle and cause a subsequent reduction in the observed frequency of mitotic figures can be classified as an inhibitor of mitotic entry. Those herbicides that affect the mitotic sequence(mitosis) by influencing the development of the spindle apparatus or by influencing new cell plate formation should be classified as causing disruption of the mitotic sequence. Sulfonylureas, imidazolinones, chloroacetamides and some others inhibit plant growth by inhibiting the entry of cell into mitosis. The carbamate herbicides asulam, carbetamide, chlorpropham and propham etc. reported to disrupt the mitotic sequence, especially affecting on spindle function, and the dinitroaniline herbicides trifluralin, nitralin, pendimethalin, dinitramine and oryzalin etc. reported to disrupt the mitotic sequence, particularly causing disappearence of microtubles from treated cells due to inhibition of polymerization process. An inhibition of cell enlargement can be made by membrane demage, metabolic changes within cells, or changes in processes necessary for cell yielding. Several herbicides such as diallate, triallate, alachlor, metolachlor and EPTC etc. reported to inhibit cell enlargement, while 2, 4-D has been known to disrupt cell enlargement. One potential danger inherent in the use of soil acting herbicides is that build-up of residues could occur from year to year. In practice, the sort of build-up that would be disastrous is unikely to occur for substances applied at the correct soil concentration. Crop injury caused by soil applied herbicides can be minimized by (1) following the guidance of safe use of herbicides, particularly correct dose at correct time in right crop, (2) by use of safeners which protect crops against injury without protecting any weed ; interactions between herbicides and safeners(antagonists) at target sites do occur probably from the following mechanisms (1) competition for binding site, (2) circumvention of the target site, and (3) compensation of target site, and another mechanism of safener action can be explained by enhancement of glutathione and glutathione related enzyme activity as shown in the protection of rice from pretilachlor injury by safener fenclorim, (3) development of herbicide resistant crops ; development of herbicide-resistant weed biotypes can be explained by either gene pool theory or selection theory which are two most accepted explanations, and on this basis it is likely to develop herbicide-resistant crops of commercial use. Carry-over problems do occur following repeated use of the same herbicide in an extended period of monocropping, and by errors in initial application which lead to accidental and irregular overdosing, and by climatic influence on rates of loss. These problems are usually related to the marked sensitivity of the particular crops to the specific herbicide residues, e.g. wheat/pronamide, barley/napropamid, sugarbeet/ chlorsulfuron, quinclorac/tomato. Relatively-short-residual product, succeeding culture of insensitive crop to specific herbicide, and greater reliance on postemergence herbicide treatments should be alternatives for farmer practices to prevent these problems.