• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.15-18
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• 1996

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1189-1193
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• 2006

In order to develop radiopharmaceuticals for targeting a serotonin receptor such as $5-HT_{1A}$, histidine-$C_n$-arylpiperazines (AP) (C = alkyl, n = 2, 3, 4) were prepared in five steps with yields of 25%, 37% and 51%, respectively, and radiolabeled with the $[^{99m}Tc(CO)_3(H_2O)+3]^+$. The $^{99m}Tc(CO)_3$-Histidine-Cn-APs were prepared with a high yield (>99%) and characterized as a tridentate complex with a neutral charge to pass through the blood-brain barrier (BBB). The rhenium complexes with $Re(CO)_3$ were also synthesised and comparative experiments were achieved to evaluate the nature of the $^{99m}Tc$ complexes.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1689-1692
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• 2006

• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.425-434
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• 2008

Dopamine transporter imaging is useful in the diagnosis of Parkinson's disease and the most successful technique in the clinical use of neuroreceptor imaging. Recently, several radiopharmaceuticals including I-123 FP-CIT, Tc-99m TRODAT, and F-18 FP-CIT for dopamine transporter imaging have been approved for the routine clinical use in several European countries, Taiwan and Korea, respectively. This review summarized the practical issue for the routine clinical examination of dopamine transporter imaging.

• Applied Microscopy
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• v.25 no.1
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• pp.48-64
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• 1995

Ultrastructure of nerves and their associated cells in the bronchiolar epithelium of the human fetal lung were studied with ultrastructural and immunohistochemical methods. The neuroendocrine cells were scattered along the basal part of non-ciliated respiratory epithelium and appeared as single cell (solitary neuroendocrine cell) or groups (neuroepithelial bodies). The solitary neuroendocrine cells were devoid of any detectable innervation, while the neuroepithelial bodies were associated with nerve ending containing morphologically afferent (sensory) and efferent (motor) intraepithelial terminals. The afferent nerve endings contained abundant mitochondria with long cristae. The efferent nerve endings were characterized by the presence of synaptic vesicles. Both types of nerve endings formed synaptic junction between nerve endings and neuroepithelial bodies cells. Serial sections of the intraepithelial nerves revealed that both morphologically afferent and efferent types of nerve endings may be formed by the same nerve fiber. By immunohistochemistry, bombesin and serotonin were localized in solitary neuroendocrine cells and neuroepithelial bodies of human fetal lung from various prenatal age groups. These results suggest that the neuroepithelial bodies cells of the human fetal lung have neuroreceptor function.

• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.161-170
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• 2004

Molecular Nuclear Neuro-Imaging in "CNS" drug discovery and development tan be divided into four categories that are clearly inter-related.(1) Neuroreceptor mapping to examine the involvement of specific neurotransmitter system in CNS diseases, drug occupancy characteristics and perhaps examine mechanisms of action;(2) Structural and spectroscopic imaging to examine morphological changes and their consequences;(3) Metabolic mapping to provide evidence of central activity and "CNS fingerprinting" the neuroanatomy of drug effects;(4) Functional mapping to examing disease-drug interactions. In addition, targeted delivery of therapeutic agents could be achieved by modifying stem cells to release specific drugs at the site of transplantation('stem cell pharmacology'). Future exploitation of stem cell biology, including enhanced release of therapeutic factors through genetic stem cell engineering, might thus constitute promising pharmaceutical approaches to treating diseases of the nervous system. With continued improvements in instrumentation, identification of better imaging probes by innovative chemistry, molecular nuclear neuro-imaging promise to play increasingly important roles in disease diagnosis and therapy.

• Anxiety and mood
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• v.3 no.2
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• pp.91-96
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• 2007

Panic disorder is a common psychiatric illness that causes considerable morbidity. However, the biological basis of panic disorder remains unclear. In this report, we present and summarize the current literature on functional neuroimaging studies related to the neurobiology of panic disorder. The findings were summarized and divided into six groups : (1) known brain structures related to anxiety, especially panic disorder ; (2) structural results ; (3) functional imaging studies at rest ; (4) functional imaging studies with challenge testing ; (5) neuroreceptor studies ; and (6) changes in the treatment of panic disorder. Based on the findings of these neuroimaging studies, it seems as though panic disorder involves the hippocampal and parahippocampal areas, including the amygdala, as well as some cortical regions, such as the temporal and prefrontal cortices. Panic disorder is known to be associated with an imbalance between the right and left hemispheres of the brain at rest or during panic attacks. During a panic attack, patients with panic disorder are likely to experience an increase in local activity in the cingulate, insula, midbrain, and so on. On the other hand, a widespread reduction in the cortical areas has also been reported in most provocation studies. Thus, panic disorder may be related to the excess activation of the fear networks in response to subtle environmental cues and insufficient inhibition from higher cortical control areas ; however ; further studies are recommended in order to fully understand the neurobiology of panic disorder.

• Journal of Animal Reproduction and Biotechnology
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• v.36 no.4
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• pp.270-284
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• 2021

The vomeronasal organ (VNO) is critical for reproduction and social behavior in ruminants, including cattle. The present study examined the structure of the VNO and its epithelial cells in neonatal and adult Korean native cattle (Hanwoo), Bos taurus coreanae, using immunohistochemistry and lectin histochemistry. Histologically, the VNO comprised two types of epithelia: medial vomeronasal sensory (VSE) and lateral vomeronasal non-sensory epithelia (VNSE). Numerous blood vessels and nerve bundles were observed within the vomeronasal cartilage encased lamina propria. Immunohistochemistry revealed high expression level of protein gene product9.5 and moderate expression level of olfactory marker protein in the neuroreceptor cells of the VSE and occasionally in some ciliated cells of the VNSE in both neonates and adults. The properties of the glycoconjugates in the VNO were investigated using 21 lectins, most of which were expressed at varied intensities in the VSE and VNSE, as well as in the lamina propria. Several lectins exhibited variations in their intensities and localization between neonatal and adult VNOs. This study is the first descriptive lectin histochemical examination of the VNO of Korean native cattle with a focus on lectin histochemistry, confirming that the VNO of Korean native cattle is differentiated during postnatal development.

• The Korean Journal of Nuclear Medicine
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• v.18 no.2
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• pp.17-23
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• 1984

For nearly a century it has been known that chemical activity accompanies mental activity, but only recently has it been possible to begin to examine its exact nature. Positron-emitting radioactive tracers have made it possible to study the chemistry of the human mind in health and disease, using chiefly cyclotron-produced radionuclides, carbon-11, fluorine-18 and oxygen-15. It is now well established that measurable increases in regional cerebral blood flow, glucose and oxygen metabolism accompany the mental functions of perception, cognition, emotion and motion. On May 25, 1983 the first imaging of a neuroreceptor in the human brain was accomplished with carbon-11 methyl spiperone, a ligand that binds preferentially to dopamine-2 receptors, 80% of which are located in the caudate nucleus and putamen. Quantitative imaging of serotonin-2, opiate, benzodiazapine and muscarinic cholinergic receptors has subsequently been accomplished. In studies of normal men and women, it has been found that dopamine and serotonin receptor activity decreases dramatically with age, such a decrease being more pronounced in men than in women and greater in the case of dopamine receptors than serotonin-2 receptors. Preliminary studies in patients with neuropsychiatric disorders suggests that dopamine-2 receptor activity is diminished in the caudate nucleus of patients with Huntington's disease. Positron tomography permits quantitative assay of picomolar quantities of neuro-receptors within the living human brain. Studies of patients with Parkinson's disease, Alzheimer's disease, depression, anxiety, schizophrenia, acute and chronic pain states and drug addiction are now in progress. The growth of any scientific field is based on a paradigm or set of ideas that the community of scientists accepts. The unifying principle of nuclear medicine is the tracer principle applied to the study of human disease. Nineteen hundred and sixty-three was a landmark year in which technetium-99m and the Anger camera combined to move the field from its latent stage into a second stage characterized by exponential growth within the framework of the paradigm. The third stage, characterized by gradually declining growth, began in 1973. Faced with competing advances, such as computed tomography and ultrasonography, proponents and participants in the field of nuclear medicine began to search for greener pastures or to pursue narrow sub-specialties. Research became characterized by refinements of existing techniques. In 1983 nuclear medicine experienced what could be a profound change. A new paradigm was born when it was demonstrated that, despite their extremely low chemical concentrations, in the picomolar range, it was possible to image and quantify the distribution of receptors in the human body. Thus, nuclear medicine was able to move beyond physiology into biochemistry and pharmacology. Fundamental to the science of pharmacology is the concept that many drugs and endogenous substances, such as neurotransmitters, react with specific macromolecules that mediate their pharmacologic actions. Such receptors are usually identified in the study of excised tissues, cells or cell membranes, or in autoradiographic studies in animals. The first imaging and quantification of a neuroreceptor in a living human being was performed on May 25, 1983 and reported in the September 23, 1983 issue of SCIENCE. The study involved the development and use of carbon-11 N-methyl spiperone (NMSP), a drug with a high affinity for dopamine receptors. Since then, studies of dopamine and serotonin receptors have been carried out in over 100 normal persons or patients with various neuropsychiatric disorders. Exactly one year later, the first imaging of opitate receptors in a living human being was performed [1].

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.1-7
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• 2002

Positron Emission Tomography (PET) is a nuclear medicine imaging modality that consists of systemic administration to a subject of a radiopharmaceutical labeled with a positron-emitting radionuclide. Following administration, its distribution in the organ or structure under study can be assessed as a function of time and space by (1) defecting the annihilation radiation resulting from the interaction of the positrons with matter, and (2) reconstructing the distribution of the radioactivity from a series of that used in computed tomography (CT). The nuclides most generally exhibit chemical properties that render them particularly desirable in physiological studies. The radionuclides most widely used in PET are F-18, C-11, O-15 and N-13. Regarding to the number of the current PET Centers worldwide (based on ICP data), more than 300 PET Centers were in operation in 2000. The use of PET technology grew rapidly compared to that in 1992 and 1996, particularly in the USA, which demonstrates a three-fold rise in PET installations. In 2001, 194 PET Centers were operating in the USA. In 1994, two clinical and research-oriented PET Centers at Seoul National University Hospital and Samsung Medical Center, was established as the first dedicated PET and Cyclotron machines in Korea, followed by two more PET facilities at the Korea Cancer Center Hospital, Ajou Medical Center, Yonsei University Medical Center, National Cancer Center and established their PET Center. Catholic Medical School and Pusan National University Hospital have finalized a plan to install PET machine in 2002, which results in total of nine PET Centers in Korea. Considering annual trends of PET application in four major PET centers in Korea in Asan Medical Center recent six years (from 1995 to 2000), a total of 11,564 patients have been studied every year and the number of PET studies has shown steep growth year upon year. We had 1,020 PET patients in 1995. This number increased to 1,196, 1,756, 2,379, 3,015 and 4,414 in 1996,1997,1998,1999 and 2000, respectively. The application in cardiac disorders is minimal, and among various neuropsychiatric diseases, patients with epilepsy or dementia can benefit from PET studios. Recently, we investigated brain mapping and neuroreceptor works. PET is not a key application for evaluation of the cardiac patients in Korea because of the relatively low incidence of cardiac disease and less costly procedures such as SPECT can now be performed. The changes in the application of PET studios indicate that, initially, brain PET occupied almost 60% in 1995, followed by a gradual decrease in brain application. However, overall PET use in the diagnosis and management of patients with cancer was up to 63% in 2000. The current medicare coverage policy in the USA is very important because reimbursement policy is critical for the promotion of PET. In May 1995, the Health Care Financing Administration (HCFA) began covering the PET perfusion study using Rubidium-82, evaluation of a solitary pulmonary nodule and pathologically proven non-small cell lung cancer. As of July 1999, Medicare's coverage policy expanded to include additional indications: evaluation of recurrent colorectal cancer with a rising CEA level, staging of lymphoma and detection of recurrent or metastatic melanoma. In December of 2001, National Coverage decided to expand Medicare reimbursement for broad use in 6 cancers: lung, colorecctal, lymphoma, melanoma, head and neck, and esophageal cancers; for determining revascularization in heart diseases; and for identifying epilepsy patients. In addition, PET coverage is expected to further expand to diseases affecting women, such as breast, ovarian, uterine and vaginal cancers as well as diseases like prostate cancer and Alzheimer's disease.