Kim, Byung-Min;Sung, Iel-Yong;Park, Bong-Soo;Shin, Sang-Hoon;Kim, Jong-Ryoul
Journal of the Korean Association of Oral and Maxillofacial Surgeons
/
v.29
no.6
/
pp.397-406
/
2003
The purpose of this study was to observe the titanium implant osseointegration in the osteoporosis-induced animal model. Seventy rats, 11 weeks of age, were divided into two groups : an ovariectomized group and a control group. Titanium screw implants(diameter, 2.0mm; length, 3.5mm) were placed into left tibias of 70 rats, 35 in the control group and 35 in the experimental group. The rats were sacrificed at different time interval (1, 2, 3, 4, 6, 8, and 12 weeks after implantation) for histopathologic observation, histomorphometric analysis and immunohistochemistry with fibronectin and CD34 antibody. The results obtained from this study were as follows: 1. Histopathologically findings, newly formed bone was seen at 3 weeks and became lamellar bone at 8 weeks, and mature trabecullar bone was seen at 12 weeks control group. In experimental group, thickness of regenerated bone increased till 8 weeks gradually and mature trabecullar bone was seen at 12 weeks. 2. By histomorphometric analysis, marrow bone density and contact ratio of marrow bone to implant decreased significantly from 8 to 12 weeks in experimental group compared to control group and also total bone to implant contact ratio decreased significantly from 8 to 12 weeks in experimental group. 3. Fibronectin immunoreactivity was strong at 3 weeks control group and reduced after 8weeks gradually. But it was continuously strong from 3 to 8 weeks in experimental group. 4. CD34 immunoreactivity was very strong in the newly formed osteoblasts from 3 to 8 weeks control group. But it reacted minimally later. While in experimental group, it reacted continuously strong from 3 to 12 weeks. The results of this study suggest that osteoporosis is not an absolute contraindication to dental implantation if sufficient period suggested after fixture installation till second stage surgery.
Park, Sung-Hwan;Park, In-Jae;Yun, Ji-Hyun;Choi, Goo-Hee;Kim, Hyun-Jung;Seo, Yun-Hee;Cho, Ju-Hyun
Food Science and Preservation
/
v.24
no.7
/
pp.1017-1024
/
2017
The objective of this study was to investigate the inhibitory effects of Litsea japonica fruit flesh extract (LJF-HE) on gastritis in an indomethacin-induced SD rat model. Rats were randomly divided into six groups: G1 (normal group), G2 (control group, indomethacin-induced gastritis), G3 (positive group, indomethacin-induced gastritis and ranitidine 50 mg/kg), G4 (LJF-HE-L group, indomethacin-induced gastritis and L. japonica fruit flesh extract at 30 mg/kg), G5 (LJF-HE-M group, indomethacin-induced gastritis and L. japonica fruit flesh extract at 60 mg/kg), G6 (LJF-HE-H group, indomethacin-induced gastritis and L. japonica fruit flesh extract at 120 mg/kg). In the group treated with LJF-HE (G4, G5, and G6), gastric mucosal damage, gastric juice secretion and pepsin activity were significantly decreased compared to the control group. Additionally, there were decreases in the expression of cholecystokinin 2 receptor (CCK-2r), histamine receptor H2 (H2r) and H+/K+ ATPase in the gastric lesions. The plasma levels of TNF-${\alpha}$ and IL-$1{\beta}$ significantly decreased in LJF-HE (G4, G5, and G6) treated groups compared with control. The plasma level of PGE2 was also significantly increased by LJF-HE (G5 and G6). These results suggest that LJF-HE (G4, G5, and G6) has the ability to inhibit on indomethacin-induced gastritis.
We investigated that the role of nitric oxide (NO) on ischemic rats in brain and heart. Ischemia was induced by both common carotid arteries (CCA) occlusion for 24h following reperfusion. Then tissue samples were removed and measured NOx. In brain, NOx was increased by about 40% vs. normal and it was significantly inhibited by aminoguanidine, selective iNOS inhibitor. This result showed that NOx concentration was increased by iNOS. We investigated the role of $Ca^{2+}$ during ischemia. Nimodipine, L-type calcium channel blocker, didn't inhibit the increases of NOx concentration during ischemia. It suggested that increased NOx was due to calcium-independent NOS. MK-801, which N-methyl-D-aspartate (NMDA) receptor antagonist, didn't significantly prevent the increases of NOx. In heart, ischemia caused NOx decrease and it is inconsistent with NOx increase in brain. Aminoguanidine and nimodipine didnt affect on NOx decrease. But MK-801 more lowered NOx concentration than those of ischemia control group. It seemed that $Ca^{2+}$ influx in heart partially occurred via NMDA receptor and inhibited by NMDA receptor antagonist. The mean arterial pressure (MAP) in ischemic rats after 24h of CCA occlusion was decreased when compared to normal value, whereas the heart rates (HR) was not different between two groups. Aminoguanidine or MK801 had no effect on MAP or HR, but nimodipine reduced MAP. There was no difference the effects of aminoguanidine, nimodipine, or MK-801, on MAP and HR between normal rats and ischemic rats. In summary, ischemic model caused an increase of NOx concentration, suggesting that this may be produced via iNOS, which is calcium independent in brain. However in heart, ischemia decreased NOx concentration and NMDA receptor was partially involved. The basal MAP was decreased in ischemic rats but HR was not different from normal control, suggesting that increased NOx in brain of ischemic rat may result in the hypotension.
The aim of this study was to investigate whether intracisternal administrations of triptolide and N-nitro-L-arginine Methyl Ester (L-NAME) are involved in the regulation of temporomandibular joint (TMJ) pain. The TMJ pain was induced by the injection of 5% formalin ($30{\mu}l$) into TMJ capsule of rats. The pain behavioral responses was recorded the number of grooming or scratching on the left TMJ area for 9 successive 5 minutes intervals. Triptolide and L-NAME were administrated intracisternally 10 minutes before formalin injection. The intra-articular injection of formalin produced a biphasic pattern of pain response (first phase: 0~10 minutes and second phase: 11~45 minutes). The intracisternal administration of triptolide ($1{\mu}g/10{\mu}l$) and L-NAME ($0.1{\mu}g/10{\mu}l$) suppressed the TMJ pain behavior in each experiment. Co-administration of two drugs was shown the enhanced effect than the analgesic effect by single-administration of triptolide ($1{\mu}g/10{\mu}l$). The triptolide could be a useful analgesic agent for the treatment of TMJ pain, and it is expected to reduce the substantial amount of it via co-administration of synthetic chemical compound and natural products.
Sera from male Spague-Dawley rats, exposed to $30\\pm 0.5^\\circ C$ for 240 hours or $33\\pm 0.5^\\circ C$ for 64 hours, were assayed for the activities of serum glutamic oxaloacetic transaminase(SGOT) and serum glutamic pyruvic transaminase(SGPT) at various time during the heat exposure. 1. When compared to control animals maintained at $23\\pm 1^\\circ C$, the animals exposed to $30\\pm 0.5^\\circ C$ ro $33\\pm 0.5^\\circ C$ showed a significant increase in SGOT and SGPT activities, 2. The SGOT activity incressed at 16 and 72 hours after the exposure to $30^\\circ C$, and at 30 and 64 hours after the exposure to $33^\\circ C$. After 72 hours, the activity returned to the initial value in case of $30^\\circ C$ exposure. 3. The SGPT activity increased significantly as early as 4 hours after the exposure to $30^\\circ C$ or $33^\\circ C$. It was also high at 16 hours after the exposure. The activity was also high at 72 hours and at 64 hours after the exposure to $30^\\circ C$ and $33^\\circ C$ respectively. After 144 hours, SGPT level increased slightly in the case of $30^\\circ C$ exposure. 4. The activities of SGOT and SGPT were significantly higher in rats exposed to $33^\\circ C$ at 16, 30, and 64 hours than those exposed to $30^\\circ C$. 5. It may be inferred from above data that the prolonged heat exposed rat has the abnormal metabolism of transamination.
Park, Suk-jae;Hwang, In-sun;Kim, Gyu-beom;Shin, Tae-kyun;Jee, Young-heun
Korean Journal of Veterinary Research
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v.46
no.3
/
pp.177-184
/
2006
Experimental autoimmune encephalomyelitis (EAE) is a disease model of multiple sclerosis (MS) that is characterized by remittance and relapse of the disease and autoimmune and demyelinating lesions in the central nervous system (CNS). Autoimmune inflammation is maintained by secretion of a large number of protein. Previous studies have suggested that transcripts encoding osteopontin (OPN) are frequently detected in the mRNA population of MS plaques. To elucidate the functional role of OPN in initiation and development of EAE, we examined the expression and localization of OPN in the spinal cord during acute EAE. We demonstrated that OPN significantly increased at the early stage of EAE and slightly declined thereafter by western blot analysis. An immunohistochemical study revealed that OPN was constitutively expressed in some glial cells (microglia, astrocytes) of white matter and neurons in the CNS of control rats. OPN expression was shown to be increased in the same cells at the early and peak stage of EAE. To identity cells expressing OPN by double-immunofluorescence labeling, we labeled rat spinal cord sections for OPN with a monoclonal OPN antibody and with mAbs for astrocyte (GFAP), microglia/macrophage (OX42)-specific markers. The major cell types of OPN-expressing cells were activated astrocytes and microglia in the adjacent inflammatory lesions. Interestingly, OPN was mainly expressed in the end feet of astrocytes around vascular cell adhesion molecule-1 (VCAM-1) expressing endothelial cells of CNS blood vessel. These findings suggest that increased levels of OPN in activated glial cell may play an important role in the recruitment of inflammatory cells into the CNS parenchyma during EAE.
Lee, Heun Joo;Jeong, Bo Eun;Song, Da Eun;Park, Min Young;Koo, Sungtae
Korean Journal of Acupuncture
/
v.30
no.1
/
pp.56-63
/
2013
Objectives : Effects of repetitive electroacupuncture(EA) on the pain behavior and activation of spinal glial cells were examined in the rat model of neuropathic pain. Methods : Twenty one adult male Sprague-Dawley rats were randomly assigned into 3 groups(control group, SP6 group, ST36+GB34 group). Neuropathic pain was induced by tight ligation of L5 spinal nerve. Mechanical and thermal hypersensitivity of hind paw were tested. Immunohistochemistry was performed in spinal cord L5/6 of all groups. EA was treated once in a day from the $5^{th}$ day after surgery. Results : EA treatments applied to ST36 and GB34 reduced significantly both of mechanical and thermal hypersensitivity after 3 times of treatment throughout the experiments. In the SP6 group, the analgesic effect was also shown after 7 times of treatment. Immunohistochemistry demonstrated inhibition of microglia and astrocyte activation in the spinal cord L5/6 dorsal horn in the ST36+GB34 group. Conclusions : The present results suggest that repetitive EA exert strong analgesic effect on neuropathic pain. These analgesic effects in neuropathic pain are associated with suppressing the activation of microglia and astrocyte.
Park, Hyun-Joo;Kim, Jong-Gab;Yoon, Sik;Bae, Moon-Kyoung;Bae, Soo-Kyung
Journal of Life Science
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v.19
no.8
/
pp.1067-1072
/
2009
Stromal derived factor-1 (SDF-1 or CXCL12), one of the CXC chemokines, is widely expressed in many tissues, including the thymus. The thymus can regenerate to its normal mass within 14 days after acute involution induced by cyclophosphamide (CY) in adult rats. Despite the established role of SDF-1 signaling in the development of T and B lymphocytes in the thymus, it has not yet been associated with the regeneration of the adult thymus. The purpose of this study was to investigate whether SDF-1, which is expressed in thymic stromal cells, is modulated during thymic regeneration in adult rats. Here, we showed that SDF-1 mRNAs were expressed in high levels in the thymocyte and thymic stromal cells at day 7 of the CY model. SDF-1 protein was shown to be present at the cortex-medulla junction, paraseptum and within the thymic medulla. Double-immunofluorescence for SDF-1 and ED-1 showed that strong SDF-1 expression was detected in the macrophages of the medulla region displaying immunoreactivity for ED-1 during thymus regeneration. Taken together, our results demonstrated that SDF-1 expression increased in regenerating thymic macrophages, suggesting the roles of SDF-1 as a chemo-attractant for damaged cells produced in the process of thymic regeneration after acute involution induced by CY.
The purpose of this study was to observe the effect of dexamethasone and osteogenic protein-1(BMP-7) on bone, cementum and periodontal tissue regeneration. A total of 60 Sprague-Dawley white female mice were selected and beta-APN was used for five days to extract the maxillary first molar a traumatically. After the extraction of the teeth, the mesiobuccal root canal was filled with Caviton$^{\circledR}$. The teeth were etched with citric acid for 1 min and coated with one of four different experimental solutions : DEX(500nM/ml), DEX(1000nM/ml), OP-1(100$\mu\textrm{g}$/ml) and OP-1(500$\mu\textrm{g}$/ml) for three minutes depending on the group. All teeth were then replanted under microscope. All replantation procedures were done within 30 minutes. Teeth that were replanted after 30 minutes of bench dry only was used as positive control. All animals were sacrificed at 3 weeks following replantation and histologic observtion was done. The results were as follows ; 1. Active root resorption rate was decreased by the order of OP-1(500$\mu\textrm{g}$/ml), DEX(1000nM/ml), OP-1(100$\mu\textrm{g}$/ml), and DEX(500nM/ml). There was statistically less root resorption in OP-1 (500$\mu\textrm{g}$/ml) and DEX(1000nM/ml) group(P<0.05). 2. The group with higher concentration of dexamethasone(1000nM/ml) had statistically more bone union compared to positive control group(P<0.05),but there were no significant differences among four experimental groups. 3. OP-1(500$\mu\textrm{g}$/ml) and DEX(1000nM/ml) groups showed less degree of inflammation compared to the OP-1(100$\mu\textrm{g}$/ml). DEX(500nM/ml), and positive control group (P<0.05). In conclusion, the group with higher concentration of OP-1 had the best results on root resorption, bone ankylosis and anti-inflammatory effects compared to the other experimental groups, but a long-term study is also necessary to evaluate the exact pharmacological effects of the drugs in the future.
Background: Ginseng, the root of Panax ginseng (PG), is used widely as a herbal medicine to prevent and treat various diseases. Panax ginseng has pharmacological effects on neurodegenerative diseases such as Alzheimer's disease (AD). The present study evaluated the neuroprotective effects of PG and its possible neuroprotective mechanisms in advanced glycation end product (AGE)-induced AD in a rat model. Methods: Advanced glycation end products were injected bilaterally into the CA3 region of the rats' brains. The Morris water maze test and step-down type passive avoidance test were performed to evaluate their memory and cognitive abilities. The oxidation indexes in the hippocampus were detected. Immunohistochemistry was conducted to visualize the receptors for advanced glycation end products (RAGEs) and nuclear factor-kappa-light-chain-enhancer of activated B cell (NF-${\kappa}B$). Results: Behavioral results showed that PG (1 g/kg, 0.5 g/kg, and 0.25 g/kg) significantly shortened the escape latency, remarkably increased the number of crossing times, significantly decreased the number of errors, and prolonged the latency in rats with AGE-induced AD. Panax ginseng also significantly reduced the malondialdehyde level, increased the glutathione content, and increased superoxide dismutase activity in the hippocampus. Panax ginseng significantly decreased the expression of RAGE and NF-${\kappa}B$. The blockade of anti-RAGE antibody could significantly reduce AGE-induced impairments and regulate these expressions. Conclusion: Our results demonstrated that PG significantly inhibits AGE-induced memory impairment and attenuates Alzheimer-like pathophysiological changes. These neuroprotective effects of PG may be associated with the RAGE/NF-${\kappa}B$ pathway. Our results provided the experimental basis for applying PG in preventing and treating AD.
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