• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.28-34
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• 1993

Using in vitro autoradiography with a digital autoradiography system and radioreceptor assay, the distribution and the binding characteristics of the muscarinic cholinergic receptors (mAChR) were studied in regions of rat brain. Radioreceptor assay revealed that mAChR could be measured with saturation binding assay in the brain and heart homogenates: No difference in Kd or Bmax of the brain or heart was found between the normal Wistar rats and SHR rats. Specific binding of $^3H$ quinuclidinyl benzilate (QNB) increased and saturation was reached by 2 hours after incubation with slide-mounted brain tissue. The distribution of mAChR was heterogeneous along the fields of brain. Affinity (Kd) of mAChR was not different significantly among cortex, hippocampus and caudate-putamen. No difference was found between normal rats and SHR strain. More receptors (Bmax) were found in the cortex and hippocampus than in the caudate-putamen in normal rats. More receptors were found in the cortex and caudate-putamen in SHR rats than in normal rats. Radioreceptor assay and digital autoradiographic analysis of affinity and number of mAChR gave the same results. With the above findings, we concluded that we could use digital autoradiographic system with $^3H$-QNB in the characterization of mAChR of rats and that the cortex and caudate-putamen of SHR strain rats have more receptors than those of normal rats.

• Applied Microscopy
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• v.42 no.2
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• pp.53-59
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• 2012

We evaluated the level of toxicity by LC50 and investigated the mechanism of brain impairment and GFAP expression by light and fluorescence microscopes in the pale chub, Zacco platypus, treated with fenvalerate. Survival rate was decreased according to the rise of fenvalerate concentration, and LC50 concentration was $27.79{\mu}g/L$. Apoptosis was increased according to the rise of fenvalerate concentration by TUNEL assay which determine apoptotic cell death population. Also, GFAP expression was increased in the periventricular zone. These results suggest that apoptosis might be a major mechanism to brain impairment of the pale chub by fenvalrerate. Increased GFAP expression in the periventricular zone would be an index of brain impairment. Taken together, this study might contribute to reveal the pathological mechanism of fish brain impairment by insecticide of pyrethroid, and to be an useful basic data for preservation of aquatic ecosystem.

• The Korean Journal of Nuclear Medicine
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• v.24 no.1
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• pp.93-100
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• 1990

To evaluate the utility of autoradiographic technique in the detection of TRH receptor changes in brain after the various kinds of stimulation or drug administration, we tried the characterization of TRH receptor in mouse brain and autoradiography in rat brain as a preliminary study. The Kd value of [3-H] MeTRH to TRH receptors of adult male ICR mouse brain (cebellum and spinal cord were excluded) was 3.55+0.6 nM and Bmax was 3.44+0.52 fmol/mg wet tissue by saturation analysis. The Kd value of TRH to TRH receptors was 133.8+28.2 nM by competition analysis. And we could visualize the distribution of TRH receptors in rat brain by autoradiographic technique.

• BMB Reports
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• v.56 no.2
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• pp.114-119
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• 2023

Liver fibrosis is caused by chronic liver damage and results in the aberrant accumulation of extracellular matrix during disease progression. Despite the identification of the HAT enzyme p300 as a major factor for liver fibrosis, the development of therapeutic agents targeting the regulation of p300 has not been reported. We validated a novel p300 inhibitor (A6) on the improvement of liver fibrosis using two mouse models, mice on a choline-deficient high-fat diet and thioacetamide-treated mice. We demonstrated that pathological hall-marks of liver fibrosis were significantly diminished by A6 treatment through Masson's trichrome and Sirius red staining on liver tissue and found that A6 treatment reduced the expression of matricellular protein genes. We further showed that A6 treatment improved liver fibrosis by reducing the stability of p300 protein via disruption of p300 binding to AKT. Our findings suggest that targeting p300 through the specific inhibitor A6 has potential as a major therapeutic avenue for treating liver fibrosis.

• Biomolecules & Therapeutics
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• v.24 no.6
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• pp.581-588
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• 2016

Lonchocarpine is a phenylpropanoid compound isolated from Abrus precatorius that has anti-bacterial, anti-inflammatory, antiproliferative, and antiepileptic activities. In the present study, we investigated the antioxidant effects of lonchocarpine in brain glial cells and analyzed its molecular mechanisms. We found that lonchocarpine suppressed reactive oxygen species (ROS) production and cell death in hydrogen peroxide-treated primary astrocytes. In addition, lonchocarpine increased the expression of anti-oxidant enzymes, such as heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1), and manganese superoxide dismutase (MnSOD), which are all under the control of Nrf2/antioxidant response element (ARE) signaling. Further, mechanistic studies showed that lonchocarpine increases the nuclear translocation and DNA binding of Nrf2 to ARE as well as ARE-mediated transcriptional activities. Moreover, lonchocarpine increased the phosphorylation of AMP-activated protein kinase (AMPK) and three types of mitogen-activated protein kinases (MAPKs). By treating astrocytes with each signaling pathway-specific inhibitor, AMPK, c-jun N-terminal protein kinase (JNK), and p38 MAPK were identified to be involved in lonchocarpine-induced HO-1 expression and ARE-mediated transcriptional activities. Therefore, lonchocarpine may be a potential therapeutic agent for neurode-generative diseases that are associated with oxidative stress.

• Journal of fish pathology
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• v.16 no.1
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• pp.13-21
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• 2003

The infection characteristics with scuticociliates at on-land rearing farms and hatcheries of flounder, Paralithys olivaceus was investigated during the year of 2001 by juvenile infection routes. When culture tanks for living food organisms such as chlorella, rotifer, and Artemia were searched, scuticocilates were detected both in live and dead rotifer, and at the dregs of culture tank bottoms at almost hatcheries. When rotifer infected with scuticocilates fed on fish larvae, lots of scuticocilate were inhabited at the bottom of fry rearing tanks. After feeding on scuticocilates-infected rotifer on fish larvae, first infection was detected at 10 days after bottom dwelling or 40 days old after hatching. By histopathological examination we confirmed the infection route of eyeball or brain contamination was that the ciliate worms digged through mouth and front part of the dosal fin cuticle, transferred into eyeball along the epithelium and muscle tissue, and reached finally into brain by the muscle and nerve tissue. The infection of internal organs was clarified into two routes. The first route was started from the infection at ventral and anal fin rays by the worms, and reached at the anus and rectum through the epithelium and muscle tissue. The second route was initiated from the infection at urinary organ and reached into the rectum epithelium cells, inner wall of intestine, abdominal cavity, pancreas, kidney, and pancreas. At seed production farms where fish larvae fed on scuticocilate-free rotifer, the worms were not detected not only at the food organisms culture tanks and juvenile rearing tanks but also larval flounder less than 7cm in total length.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.331-338
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• 1995

Laserthermia is a new method of local hyperthermia using fiber optic guided probe with computer controlled Nd-YAG laser system. We used a synthetic sapphire probe and allowed irradiation with contolled low power laser energy (less than 5W), in different thermal condition (temprature: 38.5~50 degrees C) for 10 minutes, in the normal brain tissue of 18 rabbits. In results, the histological changes of brain tissue was variable (myelin condensation, chromatin condensation, nuclear waving and palisading, RBC discoloration, cell necrosis) in microscopic findings after laser irradiation, but changing area was not occured proportionally in thermal condition level. Cell necrosis appears to over 44.5 degrees C and the distance was about 1.25 mm. This study, using computer controlled laserthermia system for interstitial local hyperthermia, may offer many advantages in the experimental treatment and clinical management of tumor. Minimizing normal tissue damage is now being developed.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.143-148
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• 2005

Chemotactic migration of bone forming cell, osteoblast, is an important event during bone formation, bone remodeling, and fracture healing. Migration of cells is mediated by adhesion receptors, such as integrins, that link the cell to extracellular matrix ligands, type I collagen, fibronectin, laminin and depend on interaction between integrin and extracellular ligand. Our study was designed to investigate the effect of extracellular matrix like fibronectin, laminin, type I collagen on migration of osteoblast. Migration distance and speed of MC3T3-E1 cell on extracellular matrix-coated glass were measured for 24 hours using 0.01% type I collagen, 0.01% fibronectin, 100 microliter/ml laminin. The migration distance and speed of MC3T3-E1 cell was compared using a video-microscopy system. To determine migration speed, cells were viewed with a 4 phase- contrast lens and video recorded. Images were captured using a color CCD camera and saved in 8-bit full-color mode. The migration distance on 0.01% type I collagen or 0.01% fibronectin was longer than that on $100{\mu}l/ml$ laminin-coated glass. The migration speed on fibronectin-coated glass was 68 micrometer/hour which was fastest. The migration speed on type I collagen-coated glass was similar with that on fibronectin-coated glass. The latter two migration speeds were faster than that on no-coated glass. On the other hand, the average migration speed on laminin-coated glass was 37micrometer/hour and not different from that of control group. In conclusion, the extracelluar matrix ligands such as type I collagen and fibronectin seem to play an important role in cell migration. The type I collagen or fibronectin coated scaffold is more effective for migration of osteoblast in tissue engineering process.

• Journal of Life Science
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• v.28 no.1
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• pp.1-8
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• 2018

To confirm the function of lactate dehydrogenase (LDH) (EC 1.1.1.27, LDH), its metabolism was studied by activity, kinetics, and isozyme analysis in tissues of Ldh testis-specific C expressing mice (Mus musculus) maintained in a state of starvation for 48 hr and 96 hr. In skeletal muscle, liver, and eye tissues, LDH and LDH $A_4$ activity increased and anaerobic metabolism predominated. While LDH activity in the heart and kidney tissues decreased, LDH $B_4$ activity increased and aerobic metabolism predominated, producing pyruvic acid. In the testis tissue, LDH $C_4$ activity decreased. In the brain tissue, LDH activity increased, but the isozyme change was small and the amount of pyruvic acid decreased. $K{_m}^{PYR}$ increased in tissues other than kidney tissue, and the affinity for pyruvic acid decreased. Consequently, in Ldh-A and B-expressing tissues, the activities of isozymes with higher concentrations increased. However, in Ldh-A, B, and C-expressing tissue, $C_4$ decreased and the function of the tissue also decreased. In particular, LDH in brain tissue played a role as a pyruvate reductase. Therefore, this process might be the mechanism for producing energy in the state of starvation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.4
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• pp.330-335
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• 2002

The study was performed to investigate the comparison of relative signal intensity of normal- and abnormal-side retrodiscal tissue, and relationship between clinical examination, joint effusion and relative signal intensity of retrodiscal tissue in patients with unilateral TMJ internal derangement. The study group comprised 19 females and 9 males, with a mean age of 29 years. After measurements of the signal intensity were made on the MR imager for the T2 weighted images on retrodiscal tissue and brain gray matter, we calculated relative value and tried to find relationship between clinical examination, joint effusion and relative signal intensity on normal- and abnormal-side. The results are as follows. 1. The gray matter is an appropriate reference point. 2. The relative signal intensity is high significantly in abnormal-side retrodiscal tissue compared with normal-side retrodiscal tissue. 3. The relative signal intensity is high significantly in painful joints compared with nonpainful joints and in joints with joint effusion compared with joints without joint effusion. 4. The relative signal intensity in normal joints, joints with reduction and joints without reduction is increased in order significantly.