• Journal of Radiation Protection and Research
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• v.36 no.1
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• pp.35-43
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• 2011

The PHENIX Experiment is the largest of the four experiments that have taken data at the Relativistic Heavy Ion Collider. PHENIX, the Pioneering High Energy Nuclear Interaction eXperiment, is designed specifically to measure direct probes of the collisions such as electrons, muons, and photons. The primary goal of PHENIX is to discover and study a new state of matter called the Quark-Gluon Plasma. Among many particles, muons coming from W-boson decay gives us key information to analyze the spin of proton. Resistive plate chambers are proposed as a suitable solution as a muon trigger because of their fast response and good time resolution, flexibility in signal readout, robustness and the relatively low cost of production. The RPC detectors for upgrade were assembled and their performances were evaluated. The procedure to make the detectors better was optimized and described in detail in this thesis. The code based on ROOT was written and by using this the performance of the detectors made was evaluated, and all of the modules for north muon arm met the criteria and installation at PHENIX completed in November 2009. As RPC detectors that we made showed fast response, capacity of covering wide area with a resonable price and good spatial resolution, this will give the opportunity for applications, such as diagnosis and customs inspection system.

• Clinical and Experimental Pediatrics
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• v.53 no.4
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• pp.598-602
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• 2010

Transient hyperammonemia in a newborn is an overwhelming disease manifested by hyperammonemic coma. The majority of affected newborns are premature and have mild respiratory syndrome. The diagnosis may be difficult to determine. This metabolic disorder is primarily characterized by severe hyperammonemia in the postnatal period, coma, absence of abnormal organic aciduria and normal activity of the enzymes of the urea cycle. Hyperammonemic coma may develop within 2-3 days of life, although its etiology is unknown. Laboratory studies reveal marked hyperammonemia (>$4,000{\mu}mol/L$). The degree of neurologic impairment and developmental delay in this disorder depends on the duration of hyperammonemic coma. Moreover, the infant may succumb to the disease if treatment is not started immediately and continued vigorously. Hyperammonemic coma as a medical emergency requires dialysis therapy. Here, we report a case of severe transient hyperammonemia in a preterm infant (35 week of gestation) presented with respiratory distress, seizure, and deep coma within 48 hours and required ventilatory assistance and marked elevated plasma ammonia levels. He survived with aggressive therapy including peritoneal dialysis, and was followed 2 years later without sequelae.

• Parasites, Hosts and Diseases
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• v.49 no.1
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• pp.1-8
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• 2011

The pathogenesis and pathophysiology of Acanthamoeba infections remain incompletely understood. Phospholipases are known to cleave phospholipids, suggesting their possible involvement in the host cell plasma membrane disruption leading to host cell penetration and lysis. The aims of the present study were to determine phospholipase activities in Acanthamoeba and to determine their roles in the pathogenesis of Acanthamoeba. Using an encephalitis isolate (T1 genotype), a keratitis isolate (T4 genotype), and an environmental isolate (T7 genotype), we demonstrated that Acanthamoeba exhibited phospholipase $A_2$ (PLA$_2$). and phospholipase D (PLD) activities in a spectrophotometry-based assay. Interestingly, the encephalitis isolates of Acanthamoeba exhibited higher phospholipase activities as compared with the keratitis isolates, but the environmental isolates exhibited the highest phospholipase activities. Moreover, Acanthamoeba isolates exhibited higher PLD activities compared with the PLA$_2$. Acanthamoeba exhibited optimal phospholipase activities at $37^{\circ}C$ and at neutral pH indicating their physiological relevance. The functional role of phospholipases was determined by in vitro assays using human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. We observed that a PLD-specific inhibitor, i.e., compound 48/80, partially inhibited Acanthamoeba encephalitis isolate cytotoxicity of the host cells, while PLA$_2$-specific inhibitor, i.e., cytidine 5'-diphosphocholine, had no effect on parasite-mediated HBMEC cytotoxicity. Overall, the T7 exhibited higher phospholipase activities as compared to the T4. In contract, the T7 exhibited minimal binding to, or cytotoxicity of, HBMEC.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.3
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• pp.189-230
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• 2020

The metabolic syndrome, by definition, is not a disease but is a clustering of individual metabolic risk factors including abdominal obesity, hyperglycemia, hypertriglyceridemia, hypertension, and low high-density lipoprotein cholesterol levels. These risk factors could dramatically increase the prevalence of type 2 diabetes and cardiovascular disease. The reported prevalence of the metabolic syndrome varies, greatly depending on the definition used, gender, age, socioeconomic status, and the ethnic background of study cohorts. Clinical and epidemiological studies have clearly demonstrated that the metabolic syndrome starts with central obesity. Because the prevalence of obesity has doubly increased worldwide over the past 30 years, the prevalence of the metabolic syndrome has markedly boosted in parallel. Therefore, obesity has been recognized as the leading cause for the metabolic syndrome since it is strongly associated with all metabolic risk factors. High prevalence of the metabolic syndrome is not unique to the USA and Europe and it is also increasing in most Asian countries. Insulin resistance has elucidated most, if not all, of the pathophysiology of the metabolic syndrome because it contributes to hyperglycemia. Furthermore, a major contributor to the development of insulin resistance is an overabundance of circulating fatty acids. Plasma fatty acids are derived mainly from the triglycerides stored in adipose tissues, which are released through the action of the cyclic AMP-dependent enzyme, hormone sensitive lipase. This review summarizes the latest concepts in the definition, pathogenesis, pathophysiology, and diagnosis of the metabolic syndrome, as well as its preventive measures and therapeutic strategies in children and adolescents.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.85-90
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• 1997

A new ionized sputtering process was developed to fill small trench or via using additional ionizing mechanism of sputtered particles from 32cm $AlCu_x$(x=0.5%) cathode target with rotating magnet, then drawn toward substrate by small negative DC potential. The radial uniformity in RFI magnetron sputtering was studied by plasma diagnosis and appropriate RFI coil design to improve it. Optical emission intensities of excited species. $Ar^{\circ}, \;Ar^+;Al^+, \;Al^{\circ}$ are measured across the radial direction and showed close correlation with deposit's bottom to top thickness ratios in trenches and vias of submicron opening and 1.5 aspect ratio. After increase of the diameter of RF coil from 29 cm to 32 cm and improved the power leading feedthrough symmetry by removal of asymmetric single turn region, there was an increase of uniformity from 7.5% to 1.5% in bottom to top thickness ratio in 0.6 $\mu\textrm{m}$ vias.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.445-449
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• 2010

A dog with a history of long-term phenobarbital administration presented to Seoul National University Hospital for Animals with clinical signs of footpad ulceration and facial ulcerative dermatitis. Skin lesions (facial/footpad dermatitis), histopathologic signs (parakeratotic hyperkeratosis, edema and hyperplasia of the epidermis), and liver involvement (increased plasma liver enzymes and nodular lesions) suggested a diagnosis of superficial necrolytic dermatitis (SND). The patient died suddenly at home of unknown cause after 8 months medical treatment, but intravenous amino acid supplementation and supportive hepatic medication proved as effective for the skin conditions.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.12 no.2
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• pp.99-103
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• 2012

Tyrosinemia type I is an autosomal recessive inborn error of tyrosine metabolism that caused a mutation. Clinical symptoms include progressive liver damage with liver failure, coagulopathy, hypophosphataemic rickets, renal tubular dysfunction and a high risk of hepatocellular carcinoma. If left untreated, the affected infants may die from liver failure within the first year of life. PharmacoloIcal therapy with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC) has offered an effective therapeutic option in addition to dietary restriction of tyrosine and phenylalanine. As prognosis of tyrosinemia type I is improving with early diagnosis and early treatments, it meets the criteria for a condition that would benefit from newborn screening. We report a case of tyrosinemia type I diagnosed by newborn screening and successive biochemical analysis of plasma and urine, treated by dietary restriction and NTBC.

• Clinical and Experimental Pediatrics
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• v.55 no.8
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• pp.301-305
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• 2012

Nonketotic hyperglycinemia (NKH) is a rare inborn error of amino acid metabolism. A defect in the glycine cleavage enzyme system results in highly elevated concentrations of glycine in the plasma, urine, cerebrospinal fluid, and brain, resulting in glycine-induced encephalopathy and neuropathy. The prevalence of NKH in Korea is very low, and no reports of surviving patients are available, given the scarcity and poor prognosis of this disease. In the current study, we present a patient with NKH diagnosed on the basis of clinical features, biochemical profiles, and genetic analysis. Magnetic resonance spectroscopy (MRS) allowed the measurement of absolute glycine concentrations in different parts of the brain that showed a significantly increased glycine peak, consolidating the diagnosis of NKH. In additional, serial MRS follow-up showed changes in the glycine/creatinine ratios in different parts of the brain. In conclusion, MRS is an effective, noninvasive diagnostic tool for NKH that can be used to distinguish this disease from other glycine metabolism disorders. It may also be useful for monitoring NKH treatment.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.461-466
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• 1996

Diffuse alveolar hemorrhage is a very rare manifestation in Henoch-Schoenlein purpura. Recently we experience a case of diffuse alveolar hemorrhage associated with Henoch-Schoenlein purpura which was diagnosed by typical clinical manifestation and renal biopsy. A 25 year old male was admitted due to hemoptysis and dyspnea. Chest X-ray, HRCT and BAL revealed diffuse alveolar hemorrhage. He also had a history of skin rash, polyarthralgia, and hematochezia with abdominal pain. Renal biopsy which was taken for the evaluation of microscopic hematuria showed IgA nephropathy. Under the diagnosis of Henoch-Schoenlein purpura, we treated him with solumedrol pulse therapy, plasma-pheresis and prednisolone with cytoxan. After then he showed marked improvement in clinical manifestation and was discharged with prednisolone and cytoxan.

• Tuberculosis and Respiratory Diseases
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• v.40 no.6
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• pp.709-713
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• 1993

Inflammatory pseudotumor, also known as plasma cell granuloma, is a rare, benign tumor that affects at all ages and frequently involves the lung, gastrointestinal tract, and salivary gland. They are the most common, isolated, primary lesion of the lung in children less than 16 years of age, and usually present as circumscribed, peripheral, parenchymal tumors, which may be static or increase slowly in size without causing symptoms. Surgical excision is the treatment of choice bacause of the location and benign nature of this lesion. The prognosis after resection is excellent. Adjuvant therapeutic modalities include radiation and steroid therapy. Recently, we experienced a case of inflammatory pseudotumor of the lung, the diagnosis of which was made by percutaneous fine needle aspiration cytology examination. We tried steroid and the lesions of the lung was completely resolved. We report this case with a review of literatures.