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Effects of ischemic preconditioning, KATP channel on the SOD activation and apoptosis in ischemic reperfused skeletal muscle of rat (허혈양상화와 KATP 통로가 허혈후 재관류된 흰쥐의 골격근육에서 SOD 활성 및 apoptosis에 미치는 영향)

  • Abn, Dong-choon;Paik, Doo-jin;Yang, Hong-hyun
    • Korean Journal of Veterinary Research
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    • v.39 no.5
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    • pp.878-895
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    • 1999
  • Ischemic preconditioing (IPC), i.e., a preliminary brief episode of ischemia and reperfusion, has been shown to reduce the cell damage induced by long ischemia and reperfusion. Superoxide radical which is produced during reperfusion after ischemia was recognized as a factor of the ischemic injury and it is dismutated into $H_2O_2$ and $O_2$ by two types of intracellular superoxide dismutase (SOD), Cu,Zn-SOD in cytoplasm and Mn-SOD in mitochondria. Recently oxygen free radicals are suggested to induce the apoptosis, however mechanism of the reduced apoptosis by ischemic preconditioing was unknown, while many studies performed in mammalian heart indicated that ATP-sensitive $K^+$ ($K_{APT}$) channel activation related with the protective effects. The aim of present study is to investigate 1) whether IP upregulate the Cu,Zn-SOD and Mn-SOD activities, and 2) whether ischemic preconditioning decreases apoptosis via $K_{APT}$ channel activation in timely reperfused skeletal muscle after long ishemia. The experimental animals, Sprague-Dawley rats weighing 250~300g, were divided into 8 groups; 1) control group, 2) ischemic preconditioning only groups, 3) pinacidil, a $K_{APT}$ channel opener, treatment only groups, 4) glibenclamide, a $K_{APT}$ channel blocker, treatment only groups, 5) ischemia groups, 6) ischemia after IPC groups, 7) ischemia and pinacidil treatment groups, and 8) IP and ischemia after glibenclamide pretreatment groups. Animals of the control group were administered with the vehicle (DMSO) alone. Pinacidil (1mg/kg) was administered intravenously 5 minutes after initiation of ischemia, and glibenclamide (0.5mg/kg) was injected intravenously 20 minutes before IPC. In rats that were ischemic preconditioned, the left common iliac artery was occluded for 5 minutes followed by 5 minutes of reperfusion by three times using vascular clamp. Ischemia was done by occlusion of the same artery for 4 hours. The specimens of left rectus femoris muscle were obtained immediately (0 hour), 12 hours, 24 hours after drug administrations, IP or ischemia and reperfusion. The immunoreactivities of SOD and its alterations were observed by use of sheep antihuman Cu,Zn-SOD and Mn-SOD antibodies on the $10{\mu}m$ cryosections. The incidencies of apoptosis were observed by TUNEL methods with in situ apoptosis detection kit on $6{\mu}m$ paraffine section. The results obtained were as follows : 1. After IPC, immunoreactivities of Cu,Zn-SOD mainly in the small-sized fibers were increased by 24 hours, that of Mn-SOD at 0 hour and 24 hours. 2. No significant changes in immunoreactivities of SOD was observed in the pinacidil and in the glibenclamide treatment only groups, and in the ischemia only groups. 3. The immunoreactivities of the Cu,Zn-SOD were increased in the ischemia after IPC groups and the ischemia and pinacidil treatment groups. 4. The immunoreactivities of the Cu,Zn-SOD in the IPC and ischemia after glibenclamide pretreatment groups were not increased except for the 12 hours reperfusion group. But, Mn-SOD immunoreactivities were increased in the 0 hours, 12 hours and 24 hours after reperfusion. 5. In the control group, the IPC only groups, and the pinacidil treatment only groups, negative or trace apoptotic reactions were observed, but the positive apoptotic reaction occured in the glibenclamide treatment groups. 6. Moderate or many number of apoptosis were revealed in the ischemia groups, and also the IPC and ischemia after glibenclamide pretreatment group except for 12 hours and 24 hours after reperfusion. However, the incidence of apoptosis was decreased in the ischemia after IPC groups and in the ischemia and pinacidil treatment groups. 7. There is a coincidence between the increase of Cu,Zn-SOD immunoreactivities and the decrease of apoptosis in the presence of ischemia and reperfusion. These results suggest that the protective effects of ishemic preconditioing may related to the SOD activation, and the ischemic preconditioning decreases the apoptosis partially via $K_{APT}$ channel activation in timely reperfused rat skeletal muscle. It is also suggested that inhibition of apoptosis by IPC may related with the SOD activation.

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The Effect of Genetically Modified Lactobacillus plantarum Carrying Bone Morphogenetic Protein 2 Gene on an Ovariectomized Rat

  • Jin, Eun-Sun;Kim, Ji Yeon;Yang, Jung-Mo;Kim, Jun-Sub;Min, JoongKee;Jeon, Sang Ryong;Choi, Kyoung Hyo;Moon, Gi-Seong;Jeong, Je Hoon
    • Journal of Korean Neurosurgical Society
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    • v.65 no.2
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    • pp.204-214
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    • 2022
  • Objective : Osteoporosis result from age-related decline in the number of osteoblast progenitors in the bone marrow. Probiotics have beneficial effects on the host, when administered in appropriate amounts. This study investigated the effects of probiotics expressing specific genes, especially the effects of genetically modified bone morphogenetic protein (BMP)-2-expressing Lactobacillus plantarum CJNU 3003 (LP) on ovariectomized rats. Methods : Twenty-eight female Wistar rats (250-300 g, 12 weeks old) were divided into four groups : the sham (control), the ovariectomy (OVX)-induced osteoporosis group (OVX), the OVX and LP (OVX/LP), OVX and genetically modified BMP-2-expressing LP (OVX/LP with BMP) groups. The three groups underwent bilateral OVX and two of these groups were administered two different types of LP via oral gavage daily. At 16 weeks post-OVX, blood was collected from the heart and the bilateral tibiae were extracted and were scanned by ex-vivo micro-computed tomography and stained with hematoxylin-and-eosin (H&E) and Masson's trichrome stain for pathological assessment. The serum levels of osteocalcin (OC), rat C-telopeptide of type I collagen (CTX-I), BMP-2, and receptor activator of nuclear factor-ĸB ligand (RANKL) were measured. Results : The 3D-micro-computed tomography images showed that the trabecular structure in the OVX/LP with BMP group was maintained compared with OVX and OVX/LP groups. No significant differences were detected in trabecular thickness (Tb.Th) between control and OVX/LP with BMP groups (p>0.05). Furthermore, a tendency toward increased BMD, trabecular bone volume, Tb.Th, and trabecular number and decreased trabecular separation was found in rats in the OVX/LP with BMP groups when compared with the OVX and OVX/LP groups (p>0.05). The H&E and Masson's trichrome stained sections showed a thicker trabecular bone in the OVX/LP with BMP group compared with the OVX and OVX/LP groups. There was no difference in serum levels of OC, CTX and RANKL control and OVX/LP with BMP groups (p>0.05). In contrast, significant differences were found in OC and CTX-1 levels between the OVX and OVX/LP with BMP groups (p<0.05). Conclusion : Our results showed that the expression of genetically modified BMP-2 showed inhibition effect for bone loss in a rat model of osteoporosis.

A Basic Study of Hexapod Walking Robot (6족 보행로봇에 관한 기초연구)

  • Kang, D.H.;Min, Y.B.;Iida, M.;Umeda, M.
    • Journal of Biosystems Engineering
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    • v.32 no.5
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    • pp.339-347
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    • 2007
  • A hexapod walking robot had been developed for gathering information in the field. The developed robot was $260{\times}260{\times}130$ ($W{\times}L{\times}H$, mm) in size and 14.7 N in weight. The legs had nineteen degrees of freedom. A leg has three rotational joints actuated by small servomotors. Two servomotors placed at ankle and knee played the roles of vertical joint for up and down motions of the leg and the other one placed at coxa played the role of horizontal joint for forward and backward motions. In addition, a servomotor placed at thorax between the front legs and the middle legs played the role of vertical joint for pumping the two front legs to climb stair or inclination. Walking motion of the robot was executed by tripod gait. The robot was controlled by manual remote-controller communicated by an infrared ray. Two controllers were equipped to control the walking of the robot. The sub-controller using PIC microcomputer (Microchips, PIC16F84A) received the 16 bit command signal from the manual remote controller, decoded it to 8bit and transmitted it to the main microcomputer (RENESAS, SH2/7045), which controlled the 19 servomotors using the PWM command signals. Walking speeds were controlled by adjusting the period of command cycle and the stride. Forward walking speed were within 100 cm/min to 300 cm/min. However, experimental walking speed had the error of 4-40 cm/min to compare with the theoretical one, because of slippage of the leg and the circular arc motion of servomotor of coxa.

Adsorption Characteristics of VOCs in Activated Carbon Beds (활성탄 흡착탑을 이용한 휘발성 유기화합물의 흡착특성)

  • Noh, Soon-Young;Kim, Ki-Ho;Choi, Jae-Ho;Han, Sam-Duck;Kil, In-Sub;Kim, Duk-Hyun;Rhee, Young-Woo
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.4
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    • pp.455-469
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    • 2008
  • VOCs (Volatile organic compounds) are known as one of the harmful chemicals, causing cancer and global warming. Therefore, the proper control, removal, and reduction of the emission of VOCs are important tasks for the environmental protection. Among the method of VOCs removal activated carbon bed is the most efficient and economical method. In this study, the adsorption performance of toluene gas was investigated using various activated carbons. To find out the adsorption efficiency, the H/D (Height/Diameter) of the activated carbon and GHSV (Gas Hourly Space Velocity) of the toluene gas were manipulated with various conditions. The effect of the temperature, humidity and toluene-MEK-IPA mixed gas on adsorption were also investigated. As a result, a high adsorption performance was found when GHSV is lower at room temperature and low humidity. It was also found that the adsorption efficiency of toluene-MEK-IPA mixed gas system was lower than that of toluene gas system.

Effects of low NaNO2 and NaCl concentrations on Listeria monocytogenes growth in emulsion-type sausage

  • Lee, Jeeyeon;Gwak, Eunji;Lee, Heeyoung;Ha, Jimyeong;Lee, Soomin;Kim, Sejeong;Oh, Mi-Hwa;Park, Beom-Young;Choi, Kyoung-Hee;Yoon, Yohan
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.3
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    • pp.432-438
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    • 2017
  • Objective: The objective of this study was to evaluate the effect of combinations of $NaNO_2$ and NaCl concentrations on Listeria monocytogenes (L. monocytogenes) growth in emulsion-type sausage. Methods: Emulsion-type sausages formulated with different combinations of $NaNO_2$ (0 and 10 ppm) and NaCl (1.00%, 1.25%, and 1.50%) were inoculated with a five-strain L. monocytogenes mixture, and stored at $4^{\circ}C$, $10^{\circ}C$, and $15^{\circ}C$, under aerobic or vacuum conditions. L. monocytogenes cell counts were measured at appropriate intervals, and kinetic parameters such as growth rate and lag phase duration (LPD) were calculated using the modified Gompertz model. Results: Growth rates increased (0.004 to 0.079 Log colony-forming unit [CFU]/g/h) as storage temperature increased, but LPD decreased (445.11 to 8.35 h) as storage temperature and NaCl concentration increased. The effect of combinations of NaCl and low-$NaNO_2$ on L. monocytogenes growth was not observed at $4^{\circ}C$ and $10^{\circ}C$, but it was observed at $15^{\circ}C$, regardless of atmospheric conditions. Conclusion: These results indicate that low concentrations of $NaNO_2$ and NaCl in emulsion-type sausage may not be sufficient to prevent L. monocytogenes growth, regardless of whether they are vacuum-packaged and stored at low temperatures. Therefore, additional techniques are necessary for L. monocytogenes control in the product.

Effect of Preharvest Foliar Application of Calcium Chloride on Shelf-life of Red Sweet Pepper 'Ace' (CaCl2 엽면처리가 홍단고추의 저장성에 미치는 영향)

  • Park, Sung Min;Lee, Youn Su;Jeong, Cheon Soon
    • Horticultural Science & Technology
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    • v.19 no.1
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    • pp.12-16
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    • 2001
  • This study was conducted to evaluate the effect of calcium chloride treatment (0.1%, 0.3%, and 0.5%) in red sweet pepper 'Ace' on the improvement of shelf-life and the physiological characteristics. $C_2H_4$ production and respiration rates of fruits treated with $CaCl_2$ before harvest decreased during storage of red sweet pepper at $7^{\circ}C$. Ca contents in the leaves and in the fruits showed also a greater increase in treatment of $CaCl_2$ than that in control. No difference was found in total sugar, whereas sucrose content was rapidly reduced after 20 days at $7^{\circ}C$. Ascorbic acid contents were increased by the $CaCl_2$ treatment. As Ca concentration is getting higher, the fruit decay rate was significantly reduced. From this result, we can positively conclude that foliar application with the concentration of 0.3% $CaCl_2$ and 0.5% $CaCl_2$ before harvest is effective in improving storage quality in red sweet pepper.

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Prostaglandin D2 contributes to cisplatin-induced neuropathic pain in rats via DP2 receptor in the spinal cord

  • Li, Yaqun;Kim, Woong Mo;Kim, Seung Hoon;You, Hyun Eung;Kang, Dong Ho;Lee, Hyung Gon;Choi, Jeong Il;Yoon, Myung Ha
    • The Korean Journal of Pain
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    • v.34 no.1
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    • pp.27-34
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    • 2021
  • Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a major reason for stopping or changing anticancer therapy. Among the proposed pathomechanisms underlying CIPN, proinflammatory processes have attracted increasing attention. Here we assessed the role of prostaglandin D2 (PGD2) signaling in cisplatin-induced neuropathic pain. Methods: CIPN was induced by intraperitoneal administration of cisplatin 2 mg/kg for 4 consecutive days using adult male Sprague-Dawley rats. PGD2 receptor DP1 and/or DP2 antagonists were administered intrathecally and the paw withdrawal thresholds were measured using von Frey filaments. Spinal expression of DP1, DP2, hematopoietic PGD synthase (H-PGDS), and lipocalin PGD synthase (L-PGDS) proteins were analyzed by western blotting. Results: The DP1 and DP2 antagonist AMG 853 and the selective DP2 antagonist CAY10471, but not the DP1 antagonist MK0524, significantly increased the paw withdrawal threshold compared to vehicle controls (P = 0.004 and P < 0.001, respectively). Western blotting analyses revealed comparable protein expression levels in DP1 and DP2 in the spinal cord. In the CIPN group the protein expression level of L-PGDS, but not of H-PGDS, was significantly increased compared to the control group (P < 0.001). Conclusions: The findings presented here indicate that enhanced PGD2 signaling, via upregulation of L-PGDS in the spinal cord, contributes to mechanical allodynia via DP2 receptors in a cisplatin-induced neuropathic pain model in rats, and that a blockade of DP2 receptor activation may present a novel therapeutic target for managing CIPN.

Development of a Synthetic Method for [68Ga]Ga-FAPI-04 Using a Cassette-based Synthesizer (카세트 기반 자동합성장치를 사용한 [68Ga]Ga-FAPI-04의 합성방법 연구)

  • Jun Young PARK;Won Jun KANG
    • Korean Journal of Clinical Laboratory Science
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    • v.56 no.1
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    • pp.43-51
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    • 2024
  • [68Ga]Ga-FAPI-04 is a promising radiopharmaceutical that binds specifically to fibroblast activation protein, which is overexpressed in more than 90% of malignant epithelial tumors but not in normal healthy tissue. This study aimed to develop an efficient method for producing 68Ga-labelled FAPI-04 using a cassette-based automated synthesizer. [68Ga]GaCl3 was eluted from an Eckert & Ziegler Medical germanium-68/gallium-68 generator using 2.5 mL of 0.1 M HCl. The synthesis of the [68Ga]Ga-FAPI-04 was performed using different concentrations of HEPES (1~2.5 M; 4-(2-hydroxyethyl) piperazine-1-ethanesulfonic acid) in 3~10 minutes; amounts of FAPI-04 precursor (5~50 ㎍) and reaction temperature (25℃~100℃) were optimized on the BIKBox® synthesizer. The labeling efficiency of [68Ga]Ga-FAPI-04 was greater than 96% (decay corrected) using 25 ㎍ FAPI-04 synthesized in 10 minutes at 100℃ in 2 M HEPES (pH 3.85), and its stability was greater than 99% at 6 hours. The total synthesis time of [68Ga]Ga-FAPI-04 was 32.4 minutes, and the product met all quality control criteria. In this study, we developed and optimized a labeling method using [68Ga]Ga-FAPI-04 using a cassette-based synthesizer. The devised method is expected to be useful for supplying [68Ga]Ga-FAPI-04 for diagnosis in clinical practice.

A New Approach for Hierarchical Optimization of Large Scale Non-linear Systems (대규모 비선형 시스템의 새로운 계층별 최적제어)

  • Park, Joon-Hoon;Kim, Jong-Boo
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.36T no.2
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    • pp.21-31
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    • 1999
  • This paper presents a new possibility of calculating optimal control for large scale which consist of non-linear dynamic sub-systems using two level hierarchical structures method. And the proposed method is based on the idea of block pulse transformation to simplify the algorithm and its calculation. This algorithm used an expansion around the equilibrium point of the system to fix the second and higher order terms. These terms are compensated for iteratively at the second level by providing a prediction for the states and controls which form of a part of the higher order terms. In this new approach the quadratic penalty terms are not used in the cost function. This allows convergence over a longer time horizon and also provides faster convergence. And the method is applied to the problem of optimization of the synchronous machine. Results show that the new approach is superior to conventional numerical method or other previous algorithm.

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A Study on the storage of Fresh Fruits and Vegetables (Part II) Effects of Intercellular atmosphere and Ethylene evolution by control of external pressure and gas composition in Apple Fruits. (청과물 저장에 관한 연구(제 2보) -사과 저장에 있어서 환경압력 및 기체조성이 사과조직내 기체조성과 Ethylene 생성에 미치는 영향-)

  • 손태화;최종욱;서온수
    • Microbiology and Biotechnology Letters
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    • v.1 no.1
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    • pp.25-30
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    • 1973
  • Experiments were carried out to clarify changes of intercellular gas composition, respiration and ethylene evolution by controlled external atmospheric pressure and external gas composition on apples. Jonathan apples, harvested 25, in September and Rolls apples, harvested 25, in October, 1971 and 1972 were used. Results obtained were as follows: 1. Intercellular gas volumes were proportionally changed by the given pressure, and the given pressure remarkably affected internal gas composition and volume of apples. As intercellular gas volumes were reached in their equilibrium within 5 min. after treatment, the internal atmospheric conditions became constant rapidly. 2. The increase of internal $CO_2$ production was co-related with an amount of internal $O_2$ consumption, therefore, the decreasing period of internal $O_2$ consumption was equalled to the period of climacteric rise in respiration. 3. The increasing of $CO_2$ production followed evolution of $C_2$H$_4$ and this phenomenon on SAP part. was subsequent to NAP part 4. In sub-atmospheric storage, CA effect was also obtained by control of low $O_2$ and high $CO_2$ concentration.

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