• Journal of Periodontal and Implant Science
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• v.32 no.4
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• pp.769-779
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• 2002

This present study was carried out to find the effects of calcium aluminate cement($CaO\;{\cdot}\;Al_2O_3$, CAC), which has been developed with bio-compatibility and mechanical properties, in biological environments. Two different particle sizes of CAC - 3.5${\mu}m$ vs. 212${\sim}$250${\mu}m$ which is recommended in periodontal bone grafting procedures-were filled in 8mm calvarial defect in Sprague-Dawley rat. The specimens were examined histologically, especially the bone-cement interface and the response of surrounding tissues. The results are as follows; 1. In the control group, inflammatory cells were observed at 2 weeks. At 8 weeks, periosteum and dura mater were continuously joined together in the defect areas. But in the center of defect area were filled up with the loose connective tissues. 2. In the experimental group l($212{\mu}m{\sim}250{\mu}m$ particle), immature bone was formed and outermost layer was surrounded by osteoid layer at 2 weeks. Osteoblasts were arranged between immature bone and osteoid layer. And, osteoid layer was remained until 8 weeks after surgery. 3. In the experimental group 2, periosteum and dura mater lost its continuity at 2 weeks. Scattering of CAC particles and infiltration of inflammatory cells were observed, which this findings deepened at 8 weeks. The result of this study shows that when calvarial defects in white rats are filled with calcium aluminate cement of 212${\sim}$250${\mu}m$, the materials are to be bio-compatible in growth and healing on surrounding tissues. When further researches are fulfilled, such as direct bone adhesion and bone regeneration ability, it's possible that CAC could be applied to various periodontology fields in the future.

• Molecules and Cells
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• v.43 no.4
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• pp.331-339
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• 2020

Genetic modifications in noncoding regulatory regions are likely critical to human evolution. Human-accelerated noncoding elements are highly conserved noncoding regions among vertebrates but have large differences across humans, which implies human-specific regulatory potential. In this study, we found that human-accelerated noncoding elements were frequently coupled with DNase I hypersensitive sites (DHSs), together with monomethylated and trimethylated histone H3 lysine 4, which are active regulatory markers. This coupling was particularly pronounced in fetal brains relative to adult brains, non-brain fetal tissues, and embryonic stem cells. However, fetal brain DHSs were also specifically enriched in deeply conserved sequences, implying coexistence of universal maintenance and human-specific fitness in human brain development. We assessed whether this coexisting pattern was a general one by quantitatively measuring evolutionary rates of DHSs. As a result, fetal brain DHSs showed a mixed but distinct signature of regional conservation and outlier point acceleration as compared to other DHSs. This finding suggests that brain developmental sequences are selectively constrained in general, whereas specific nucleotides are under positive selection or constraint relaxation simultaneously. Hence, we hypothesize that human- or primate-specific changes to universally conserved regulatory codes of brain development may drive the accelerated, and most likely adaptive, evolution of the regulatory network of the human brain.

• The Korea Journal of Herbology
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• v.25 no.4
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• pp.31-37
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• 2010

Objects : This study was performed in order to evaluate the effects of Agrimoniae herba (AH) ethanol extract on intrastriatal hemorrhage (ISH). Method : ISH was induced by the stereotaxic intrastriatal injection of bacterial collagenase type IV in Sprague-Dawley rats. AH was orally given once a day for 3 days after ISH. Hematoma volume and percentage edema were examined. Immunohistochemistry was processed for iNOS, c-Fos, MMP-9, and MMP-12 expressions in the brain sections and each immuno-labeling were calculated with image analysis. Results : results are as follows; 1. AH reduced the hematoma volume and percentage edema of the ISH-induced rat brain. 2. AH swollen apoptotic bodies and neurons in the peri-hematoma regions of the ISH-induced rat brain. 3. AH significantly reduced c-Fos, MMP-9 and MMP-12 positive cells in the peri-hematoma regions of the ISH-induced rat brain. 4. AH swollen iNOS expressions in the peri-hematoma regions of the ISH-induced rat brain. Conclusion : These results suggest that AH plays an anti-apoptotic neuroprotective effect through control of ISH, suppression of c-Fos, and down-regulation of MMP-9 and MMP-12 expressions in the brain tissues.

• The Journal of Korean Medicine
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• v.16 no.2 s.30
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• pp.348-364
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• 1995

Jwagyuyeum and Woogyuyeum, being known to reinforce Kidney-yin and -yang, were tested for the effects of on free radical generating enzyme and lipid peroxidation in senile rat brain. In vitro, levels of lipid peroxide in tissues of brain were proportionally decreased to concentration of extracts prepared from Jwagyuyeum and Woogyuyeum. They were much more decreased, when lipid peroxidation was induced with ferrous iron ($Fe^{-2}$). In vivo, after both berbs were administered to the rat. levels of lipid peroxide in brain were decreased. especially it was much more decreased using Jwagyuyeum. Also, enzyme activities of xanthine oxidase and aldehyde oxidase in brain were decreased. The ratio of type conversion of the brain xanthine oxidase was lowered in both, especially Jwagyuyeum was much more done. These results suggest that Jwagyuyeum and Woogyuyeum decrease the activities of free radical generating enzymes such as xanthine oxidase and aldehyde oxidase which form lipid peroxide, Consequently both herbs might delay aging.

• Molecules and Cells
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• v.40 no.8
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• pp.523-532
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• 2017

Functional near-infrared spectroscopy (fNIRS) is a noninvasive optical imaging technique that indirectly assesses neuronal activity by measuring changes in oxygenated and deoxygenated hemoglobin in tissues using near-infrared light. fNIRS has been used not only to investigate cortical activity in healthy human subjects and animals but also to reveal abnormalities in brain function in patients suffering from neurological and psychiatric disorders and in animals that exhibit disease conditions. Because of its safety, quietness, resistance to motion artifacts, and portability, fNIRS has become a tool to complement conventional imaging techniques in measuring hemodynamic responses while a subject performs diverse cognitive and behavioral tasks in test settings that are more ecologically relevant and involve social interaction. In this review, we introduce the basic principles of fNIRS and discuss the application of this technique in human and animal studies.

• BioChip Journal
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• v.12 no.4
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• pp.280-286
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• 2018

Hydrogel scaffolds composed of multiple components are promising platform in tissue engineering as a transplantation materials or artificial organs. Here, we present a new fabrication method for implementing multi-layered macroscopic hydrogel scaffold composed of multiple components by controlling height of hydrogel layer through precise control of ultraviolet (UV) energy density. Through the repetition of the photolithography process with energy control, we can form several layers of hydrogel with different height. We characterized UV energy-dependent profiles with single-layered PEGDA posts photocrosslinked by the modular methodology and examined the optical effect on the fabrication of multi-layered, macroscopic hydrogel structure. Finally, we successfully demonstrated the potential applicability of our approach by fabricating various macroscopic hydrogel constructs composed of multiple hydrogel layers.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.37-41
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• 1995

The effect of age on the metabolism of progesterone was studied in the rat brain. Metabolic activity was more active in minced tissues than total homogenates. The activity of progesterone $5{\alpha}-reductase(s)$ was increased during postnatal periods(between 5 and 14 days after birth) and thereafter steadily decreased up to the one-fourth level of the fetus. When $5{\alpha}-dihydroprogesterone$ was incubated with brain tissues of various ages, the change in the activity of $3{\alpha}-hydroxysteroid$ oxidoreductase$(3{\alpha}-HSOR)$ was similar to that of $5{\alpha}-reductase(s)$. These results suggest that the reduced formation of total $5{\alpha}-reduced$metabolites was due to the decreased activities of $5{\alpha}-reductase(s)$ and $3{\alpha}-HSOR$. However the level of $3{\beta}-HSOR$ remained constant regardless of the age.

• The Korea Journal of Herbology
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• v.27 no.2
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• pp.61-67
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• 2012

Objective : Angelica Gigas Nakai is a popular oriental medicine used for the treatment of vascular diseases. The aim of this study is to investigate neuroprotective effect of the water extract of Anelicae Gigantis Radix Palva (AG) in transient middle cerebral artery occlusion (tMCAO)-induced ischemic rats via the regulation of angiogenesis-related molecules. Methods : Sprague-Dawley rats were intraperitoneally administrated with AG water extract at doses of 10, 25, 50 mg/kg body weight after tMCAO (90 min occlusion). reperfusion for 24 hr infarction volumes were measured by 2,3,5-tetrazolium chloride (TTC) staining. Brain tissues were observed neuronal cell injuries by nissl staining, and also brain-blood barrier (BBB) permeability change by evans blue. Expression of vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1) and Tie-2 receptor protein in brain tissues was determined by western blot. Results : AG water extract significantly reduced infarction volume in ischemic brains of rats, degradation of neuronal cell, BBB permeability and expression of VEGF protein dose-dependently. Ang-1 protein was increased dose-dependantly, not significantly. Conclusion : This study suggests that AG water extract shows neuroprotective effect by preventing BBB breakdown, with regulating angiogenesis factor VEGF and Ang-1.

• Reproductive and Developmental Biology
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• v.35 no.2
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• pp.167-174
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• 2011

Acute ischemic stroke results from sudden decrease or loss of blood supply to an area of the brain, resulting in a coinciding loss of neurological function. The antioxidant action of melatonin is an important mechanism among its known effects to protective activity during ischemic/reperfusion injury. The focus of this research, therapeutic efficacy of melatonin on recovery of neurological function following long term treatment in ischemic brain injured rats. Male Sprague-Dawley rats (n=40; 8 weeks old) were divided into the control group, and MCAo groups (Vehicle, MT7 : MCAo+ melatonin injection at 7:00, MT19 : MCAo+melatonin injection at 19:00, and MT7,19 : MCAo+melatonin injection at 7:00 and 19:00). Rat body weight and neurological function were measured every week for 8 weeks. After 8 weeks, the rats were anesthetized with a mixture of zoletil (40 mg/kg) and xylazine (10 mg/kg) and sacrificed for further analysis. Tissues were then collected for RNA isolation from brain tissue. Also, brain tissues were analyzed by histological procedures. We elucidated that melatonin was not toxic in vital organs. MT7,19 was the most rapidly got back to mild symptom on test of neurological parameter. Also, exogenous melatonin induces both the down-regulation of detrimental genes, such as NOSs and the up-regulation of beneficial gene, including BDNF during long term administration after focal cerebral ischemia. Melatonin treatment reduced the loss of primary motor cortex. Therefore, we suggest that melatonin could be act as prophylactic as well as therapeutic agent for neurorehabilitative intervention.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.147-155
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• 1999

Antioxidant effects of serotonin and L-DOPA on neuronal tissues were examined by studying the oxidative damages of brain synaptosomal components. The study further explored the mechanism by which they exert protective actions. Serotonin and L-DOPA (1 ${\mu}M$ to 1 mM) significantly inhibited lipid peroxidation of brain tissues by either $Fe^{2+}$ and ascorbate or t-butyl hydroperoxide in a dose dependent fashion. Protective effect of serotonin on the peroxidative actions of both systems was greater than that of L-DOPA. Protein oxidation of synaptosomes caused by $Fe^{2+}$ and ascorbate was attenuated by serotonin and L-DOPA. Protein oxidation more sensitively responded to L-DOPA rather than serotonin. Serotonin and L-DOPA (100 ${\mu}M$) decreased effectively the oxidation of synaptosomal sulfhydryl groups caused by $Fe^{2+}$ and ascorbate. The production of hydroxyl radical caused by either $Fe^{3+},$ EDTA, H_2O_2$ and ascorbate or xanthine and xanthine oxidase was significantly decreased by serotonin and L-DOPA (1 mM). Equal concentrations of serotonin and L-DOPA restored synaptosomal $Ca^{2+}$ uptake decreased by $Fe^{2+}$ and ascorbate, which is responsible for SOD and catalase. Protective effects of serotonin and L-DOPA on brain synaptosomes may be attributed to their removing action on reactive oxidants, hydroxyl radicals and probably iron-oxygen complex, without chelating action on iron.