• Nuclear Medicine and Molecular Imaging
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• v.41 no.4
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• pp.317-325
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• 2007

Purpose: Biological parameters can be quantified using dynamic PET data with compartment modeling and Nonlinear Least Square (NLS) estimation. However, the generation of parametric images using the NLS is not appropriate because of the initial value problem and excessive computation time. In irreversible model, Patlak graphical analysis (PGA) has been commonly used as an alternative to the NLS method. In PGA, however, the start time ($t^*$, time where linear phase starts) has to be determined. In this study, we suggest a new Multiple Linear Analysis for irreversible radiotracer (MLAIR) to estimate fluoride bone influx rate (Ki). Methods: $[^{18}F]Fluoride$ dynamic PET scans was acquired for 60 min in three normal mini-pigs. The plasma input curve was derived using blood sampling from the femoral artery. Tissue time-activity curves were measured by drawing region of interests (ROls) on the femur head, vertebra, and muscle. Parametric images of Ki were generated using MLAIR and PGA methods. Result: In ROI analysis, estimated Ki values using MLAIR and PGA method was slightly higher than those of NLS, but the results of MLAIR and PGA were equivalent. Patlak slopes (Ki) were changed with different $t^*$ in low uptake region. Compared with PGA, the quality of parametric image was considerably improved using new method. Conclusion: The results showed that the MLAIR was efficient and robust method for the generation of Ki parametric image from $[^{18}F]Fluoride$ PET. It will be also a good alternative to PGA for the radiotracers with irreversible three compartment model.

• Applied Microscopy
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• v.32 no.1
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• pp.67-80
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• 2002

This study was carried out to investigate the effects of deer antler extract on the regeneration of peripheral nerves. Sprague-Dawley male rats weighing about 300 gm were fed deer antler extract for 1, 2, and 3 weeks per oral (1.5 ml/100 gm B.W.), respectively, once a day and transected both sides of sciatic nerve of each leg. After keeping for 6 hours, sciatic nerves taken from proximal part of transected region were treated with conventional transmission electron microscopical method and then observed with electron microscope. The results obtained were summarized as follows; 1. Sciatic nerves of normal control group were not showing any sprouts and electron dense axolemmal projections were frequently observed. 2. Sciatic nerves of saline treated groups were showing axonal sprouts at the nodes of Ranvier. The length of them was usually short, and numerous vesicles, vacuoles and organelles including neurofilament were contained. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 29 (29%) in 1 week treated group, 32 (32%) in 2 weeks treated group, and 30 (30%) in 3 weeks treated group, respectively. 3. Sciatic nerves of deer antler treated groups were showing axonal sprouts at the node of Ranvier as well. Although most of the sprouts were short, some sprouts of 2 weeks and 3 weeks treated groups were quite long. Sprouts usually contained numerous vesicles, vacuoles and cell organelles such as neurofilaments and mitochondria. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 38 (38%) in 1 week treated group, 46 (46%) in 2 weeks treated group, and 48 (48%) in 3 weeks treated group respectively. The results described above explain pretreatment of deer antler extract improves the sprout formation of transected sciatic nerves, and then it suggests deer antler may be effective for the regeneration of peripheral nerves.

• The Korean Journal of Nuclear Medicine
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• v.29 no.3
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• pp.294-306
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• 1995

There has recently been increasing interest in the use of NMDA receptor antagonists as potential neuroprotective agents for the treatment of ischemic stroke. To evaluate the neuroprotective effect of the selective non-competitive NMDA receptor antagonist MK-801 in focal cerebral ischemia, local cerebral glucose utilization (ICGU) was examined in 15 neuroanatomically discrete regions of the conscious rat brain using the 2-deoxy-D[$^{14}C$] glucose quantitative autoradiographic technique 24 hr after left middle cerebral artery occlusion (MCAO). Animals received MK-801 (5 mg/kg i.v.) or saline vehicle before (20-30 min) or after (30 min) MCAO. Both pretreatment and posttreatment of MK-801 increased occluded/non-occluded ICGU ratio in 7 and 5 of the 15 regions measured, respectively (most notably in cortical structures). Following MK-801 pretreatment, there was evidence of widespread increases in ICGU not only in the non-occluded hemisphere (12 of the 15 areas studied) but also in the occluded hemisphere (13 of the 15 areas studied), while MK-801 postreatment did not significantly increase ICGU both in the normal and occluded hemispheres. These data indicate that MK-801 has a neuroprotective effect in focal cerebral ischemia and demonstrate that MK-801 provides widespread alterations of glucose utilization in conscious animals.

• Radiation Oncology Journal
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• v.23 no.1
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• pp.9-16
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• 2005

Purpose : To prospectively evaluate the use of positron emission tomography with the glucose analog fluoro-deoxyglucose (FDG-PET) to deoxyglucose (FDG-PET) to predict disease-free survival (DFS) after concurrent chemo-radiotherapy (CCRT) in patients with non-disseminated nasopharyngeal carcinoma (NPC). Materials and Methods : We studied 41 patients with non-disseminated NPC scheduled to undergo platinum-based CCRT were eligible for this study. Patients were studied by FDG-PET prior to the CCRT. FDG uptake of tumors were measured with the maximal standardized uptake value (SUV). Results : Complete response rate was $100\%$. In ten patients who presented with any component of treatment failure, the median $SUV_{max}$ was 8.55 (range: $2.49\~14.81$) in any component of failure and the median $SUV_{max}$ was 5.48 (range: $2.31\~26.07$) In the remaining patients without any such failure. Patients having tumors with high FDG uptake had a significantly lower 3-year DFS ($51\%\;{\nu}91\%$, p=0.0070) compared with patients having low uptake tumors. Conclusion : FDG uptake, as measured by the SUV, has potential value in predicting DFS in NPC treated by CCRT, High FDG uptake may be a useful parameter for Identifying patients requiring more aggressive treatment approaches.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.229-236
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• 2008

Purpose: The purpose of this study was to evaluate the impact of the use of external radiation therapy (ERT) in terms of survival and compliance in patients with anaplastic thyroid carcinoma. Materials and Methods: The medical records of 17 patients with anaplastic thyroid carcinoma treated with ERT between 1993 and 2002 were retrospectively reviewed. ERT was administered after surgery in 14 patients and after a biopsy in three patients. Among the 14 patients who had undergone surgery, nine underwent a curative resection and five underwent a palliative resection. Six patients had associated well-differentiated thyroid carcinomas and 14 patients were diagnosed with a tumor size exceeding 5 cm. The radiation dose ranged from $6{\sim}70\;Gy$ (median dose, 37.5 Gy). Eleven patients completed the planned course of ERT, whereas six patients did not. The follow-up period ranged from $1{\sim}104$ months (median, 5 months; mean, 20 months). Results: Five patients started the ERT without the presence of a gross mass and all of the patients competed ERT without a re-growth of tumor. Twelve patients (four patients after a curative resection, five patients after a palliative resection and three patients after a biopsy) started ERT with a gross mass present and only six patients were able to complete the planned course of ERT. Among the six patients who completed ERT, two patients showed a marked regression of the tumor mass, whereas two patients showed slight regression and two patients showed no response. The median survival was five months (range, $1{\sim}104$ months) and the mean survival was 21 months. The overall survival was 41% at 1-year, 24% at 2-years and 12% at 5-years. Significant prognostic factors included the number of primary tumors present, tumor size, whether surgery was performed and completion of ERT as planned. Long-term survivors showed a tendency of having smaller sized initial tumors and smaller sized pre-ERT tumors than the short-term survivors. Conclusion: This study suggests that patients with a small initial tumor (${\leq}5\;cm$), which was treated by surgery (curative resection or palliative resection) before ERT, and without rapid re-growth of the mass seen at the surgical site at the beginning of the ERT course, would be the best candidates for postoperative ERT. In contrast, patients with a large initial tumor (>5 cm) and did not undergo surgery before ERT or that rapid re-growth of the mass was observed at the surgical site are likely to have a short survival time, along with the interruption of ERT. In these cases, the role of ERT is very limited and the omission of ERT could be considered.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.3 no.2
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• pp.54-58
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• 2010

Purpose: In patients with chronic cervical pain, the facet joint is the source of the majority. Due to the difficulty of identifying the exact location of the joint that causes these symptoms, the possibility of complications and the placebo effect brings clinical application into question. In this study, we assessed the prevalence of patients with chronic cervical pain and report the diagnostic and therapeutic usefulness of ultrasonography - guided facet joint block therapy. Materials and Methods: Patients with nonspecific chronic cervical pain for more than 6 months were selected. Patients with disc herniation, sciatica-related pain were excluded from the study and 160 patients who failed in conservative treatment (physical therapy, chiropractic therapy, medication) were included in the study. Diagnostic Ultrasonography-guided facet joint block was performed with 1% lidocaine, and after two weeks, Bupivacaine 0.25% was used in patients who tested positive for lidocaine. Patients with more than 75% pain reduction during movement after facet joint block were considered positive. Results: Among the 160 patients with chronic cervical pain, 96 patients(60%) had a positive reaction after facet block using lidocaine. Among the 64 patients with a negative reaction to lidocaine, 48 patients(75%) had a positive reaction to bupivacaine. There were 48 false positive patients(50%) who showed a positive reaction to lidocaine but a negative reaction to bupivacaine. The mean VAS of the total 160 patients before blocks was 8.5, after 2 weeks follow up it decreased to 2.7 (p = 0.001) and after 4weeks 3.6 (p = 0.001). The 8 patients as an initial improvement of symptoms are not satisfied with the procedure and the 3 patients had been worsened during observation, were showed pain relief after additional ultrasonography-guided facet joint block at 4th week. Conclusion: A single ultrasonography-guided block to chronic cervical pain patients has relatively low diagnostic value since high false positive rate. The twice facet joint blocks is thought to be a useful method for interventional pain management of patients with chronic cervical pain.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.281-286
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• 2011

This study was performed to investigate the effects of salted and fermented shrimp ethanol extract (SFS) on serum lipid metabolism and hepatocytes in rats. Male Sprague-Dawley rats were administered 60% fat feed to induce hypercholesterolemia and were divided into five groups. Experimental groups were classified according to administered diet: normal diet group (NC), high cholesterol diet group (HC), high cholesterol and low dose shrimp extract (20 mg/kg) group (HC-SFSL), high cholesterol and high dose shrimp extract (200 mg/kg) group (HC-SFSH), and high cholesterol and lovastatin (20 mg/kg) group (HC-Lov). The experimental diets were fed ad libitum for 14 days. Compared with the control group, the serum cholesterol and triglycerides were 40.4 and 64.7% lower in the group fed HC-SFSH respectively. Low density lipoprotein (LDL)-cholesterol concentration in serum decreased in the HC-SFSH group compared with the HC group. In a histological assay, hepatocytes in the HC group showed that the vacuolated cells by fat appear clear due to the large amount of intracytoplasmic fat, whereas the liver hepatocytes in the group fed SFS effectively decreased fatty liver and intracytoplasmic fats. These results suggest that the extract of salted and fermented shrimp has an antiatherosclerotic effect and may lessen the effects of cardiovascular disease by reducing the cholesterol level in serum.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.35-44
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• 2006

Acceleration and deceleration curves have been used for design purposes worldwide. The curve in design level has been regarded as an single deterministic curve to be used for design of climb lanes. It should be noted that the curve was originally made using ideal driving truck and that the curve is applied during design based on the assumption of no difference between ideal and real driving conditions. However. observations show that aged vehicles and lazy behavioring drivers nay make lower performance of vehicles than the ideal performance. The present paper provides the results of truck speeds at climbing lanes then probabilistic variation of acceleration and deceleration corves. For these purposes. a study about identification of vehicle makers, and weights for trucks at freeway toll gates and then observation of vehicle-following speed were performed. The 85%ile results obtained were compared with the deterministic performance curves of 180, 200, and 220 Ib/hp. It was identified that the performance of 85%ile results obtained from vehicle-following-speed observations were lower than one from deterministic performance curves. From these results, it may be concluded that at the beginning Point of climbing lanes additional $16.19{\sim}67.94m$ is necessary and that at the end point of climbing lanes $53.12{\sim}103.24m$ of extension is necessary.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.111-115
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• 2006

A feeding trial was conducted to test the use of marine yeasts isolated from seawaters and sediments as a dietary source in cultivating a Cladocera, Moina macrocopa which is available as an alternative live food for fish larvae. The marine yeast-fed M. macrocopa had similar essential amino acid profiles to the documented values for Rotifers and Artemia enriched in microalgae and commercial diets. Erythrobacter sp. $S{\pi}-1$ lacked ${\omega}-3$ high unsaturated fatty acids (HUFAs), $20:5{\omega}-3$ (EPA) and $22:6{\omega}-3$ (DHA), which were also poor but detected in both the marine yeasts. An increase in the $20:5{\omega}-3$ and $22:6{\omega}-3$ levels, compared with the levels in marine yeast strains themselves, was more pronounced in the $22:6{\omega}-3$ level of Moina fed the Candida sp. Y-16, resulting in a high DHA:EPA ratio. When the Moina diets were switched, their ${\delta}^{13}C$ values shifted gradually toward the values of the switched diets. Diet switch from Erythrobacter sp. $S{\pi}-1$to Candide sp. Y.16 resulted in a more rapid turnover of Moina tissue carbon than that in the inverse case. When fed a mixed diet, the ${\delta}^{13}C$ values of Moina tissue approached the value of marine yeasts immediately. These temporal changes in the ${\delta}^{13}C$ values of Moina tissue indicate the preferential ingestion of marine yeasts and a selective assimilation of the carbon originated from marine yeasts. These findings suggest that marine yeasts, particularly Candida sp. Y-16, are highly available to mass cultures of M. macrocopa, providing better nutritional and dietaty values than the commercial diet (Erythrobacter sp. $S{\pi}-1$).

• Journal of the Korean Society of Radiology
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• v.4 no.1
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• pp.31-35
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• 2010

Recently, the incidents of direct or indirect radiation exposure due to increase of use of radiation or radioisotope are on the increase in medical and industrial circles. If cells are irradiated, free radicals are created through biological process, and cells are directly or indirectly damaged. This research intends to explore into the effect of saponin at the level of cell (in vitro) and entity (in vivo), using red ginseng extract "saponin", as radioprotective agent. In the experiment implemented at the level of cell (in vitro), degree of cell activity was measures by adding mouse mesenchymal stem cells "C3H/10T1/2 cells" into red ginseng extract "saponin(0, 0.05, 0.2, and 0.4 g/L)", and then the optimal concentration of saponin influencing cells was calculated, in 24, 48, 72, and 96 hours after gamma irradiation at the optimal concentration of saponin, each cell survival rate was observed through XTT assay. The best time period of cultivation for the optimal activity of C3H/10T1/2 cells was as 48 hours, and the degree of optimal activity was shown at 0.05 g/L. In 48 hours after irradiation of 5 Gy to C3H/10T1/2 cells at 0.05 g/L, the degree of activity of cells increased by 10%. In the experiment implemented at the level of entity (in vivo), red ginseng extract "saponin" at a dose of 100 mg/kg/day was injected into the abdominal cavity of six-week immature mouse for two weeks. Right after the last abdominal injection, total body irradiation of gamma rays was carried out at a dose of 5 Gy and 10 Gy. And after irradiation, the blood sample was taken, and then the number of red corpuscles was counted. In result, the decrement of experimental group treated with red ginseng extract "saponin" was 2.3 times larger than that of control group. In view of the results so far achieved, it was revealed that red ginseng extract "saponin" has a radiation exposure protection effect in the experiment implemented at the level of cell (in vitro). In case of animal experiment, the decrement of number of red corpuscles decreased. Finally, it is necessary to carry out more various researches continuously.