• Title/Summary/Keyword: Gamma Detection

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Economic Analysis of Latent Tuberculosis Infection Screening Strategies in Korea (우리나라 잠복결핵감염 검진전략의 경제성 분석)

  • Kim, Sang-Won;Kang, Gil-Won;Shin, Sam-Chul;Song, Seung-Eun
    • Health Policy and Management
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    • v.23 no.4
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    • pp.349-357
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    • 2013
  • Background: Although interferon-gamma release assay (IGRA) is now available alternatives to tuberculin skin test (TST) for detection of latent tuberculosis infection (LTBI), the cost of IGRA test is much higher than TST. So economic analysis of LTBI screening strategies have been done in many countries, but there are few reports in Korea. This study examined cost analysis of LTBI screening strategies in Korea. Methods: The economic outcomes were evaluated by five strategies. These were 1) TST alone, 2) IGRA alone, 3) combination of TST and IGRA (TST followed by IGRA) and 4) no testing no prevention, 5) no testing all prevention. Last two strategies were added to compare with three main LTBI screening strategies. Decision analysis model were used to perform economic analysis. A cohort study of Korean Institute of Tuberculosis and the data of published literatures were used to estimate the cost analysis. Results: In a base-case scenario which was assumed that TST specificity was 80%, TST alone was the least expensive strategy. In a alternative scenario which was assumed that TST specificity was 97%, the combination of TST and IGRA was the least expensive strategy. Sensitivity analysis shows that patients adherent rate to LTBI treatment, TST sensitivity, IGRA sensitivity and IGRA specificity did not have a significant impact on the outcomes. Conclusion: In Korea, for the diagnosis of LTBI at the time of child and adolescent, TST alone reduces medical costs compared with IGRA alone or combination of TST and IGRA.

Analysis of Radiolytic Products of Lipid for the Detection of Irradiated Dried Cuttle Fish (Sepia officinalis) (건 갑오징어의 방사선 조사여부를 판별하기 위한 지방분해산물 분석)

  • Kim, Jun-Hyoung;Kim, Kyoung-Su
    • Korean Journal of Food Science and Technology
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    • v.35 no.6
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    • pp.1072-1078
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    • 2003
  • Radiation-induced hydrocarbons and 2-alkylcycolbutanones are formed from the fatty acids of irradiated fat. These radiation-induced compunds were detected by fat extraction with a Soxtec apparatus from dried cuttle fish (Sepia officinalis), isolation of hydrocarbons and 2-alkylcyclobutanones with florisil column chromatography, and identification of GC/MS. Concentration of hydrocarbons produced by -λ-irradiation depended on the composition of fatty acid in dried cuttle fish. The major hydrocarbons in the irradiated dried cuttle fish samples were pentadecane and 1-tetradecene from palmitic acid, heptadecane and 1-hexadecene from stearic acid, and 8-heptadecen and 1,7-hexadecadiene from oleic acid. Of 2-alkylcyclobutanones, 2-dodecylcyclobutanone from palmitic acid was present at the highest level in irradiated dried cuttle fish. The radiation-induced hydrocarbons and 2-alkylcyclobutanones from the irradiated dried cuttle fish were detected at 0.5 kGy and over, but not detected in the non-irradiated fish.

Search for the activity measurement of radionuclides I-131 (131I을 이용한 방사능 측정에 관한 연구)

  • Baek, Seong-Min;Jang, Eun-Sung
    • Journal of the Korean Society of Radiology
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    • v.6 no.1
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    • pp.79-82
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    • 2012
  • Iodine is one of important nuclides to be checked for radiation exposure after nuclear power facility accidents. After Chernobyl accident, it was observed that there is a greater amount of organic iodine in the atmosphere than inorganic iodine. In this study, we not only varied the amount of sample being exposed to $^{131}I$ and the duration of exposure to $^{131}I$ but also diluted the sample in distilled water and mixed the sample in kelp and liquid $^{131}I$ to measure and analyze the radiation detection levels. We concluded that the radiation levels were not high enough to be harmful to human body. The radiation from $^{131}I$ decreased over time, and we calculated the half life at 7-9 days. We found that the radiation from any sample containing $^{131}I$ was halved by up to 7days.

Determination and survey of tetracyclines residue in honey by high performance liquid chromatography (액체크로마토그래피를 이용한 벌꿀 중 테트라싸이클린계 항생물질의 정량분석 및 잔류조사)

  • Lee Sung-Mo;Park Eun-Jeong;Hong Jee-Young;Kim Jung-Im;Lee Jung-Goo;Hwang Hyun-Soon;Kim Yong-Hee
    • Korean Journal of Veterinary Service
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    • v.28 no.3
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    • pp.203-213
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    • 2005
  • Oxytetracycline, tetracycline, chlortetracycline and doxycycline in honey were separated by solid phase extraction (SPE) and determined with high performance liquid chromatography (HPLC) with UV/Visible detector. Analysis was carried out using following conditions: XTerra $C_8$ column $(3.9\times150mm\;i.d. 5{\mu}m)$, mobile phase composed of 0.01M oxalic acid : methanol : acetonitrile (820 : 80 : 100, v/v/v), isocratic pump at a flow rate of 0.9 ml/min. and $50{\mu}l$ of injection volume, UV/Visible detector with wavelength of 360nm. The calibration curves of four tetracyclines showed linearity $(\gamma^2>0.999)$ at concentration range of $100\~1,000 ng/ml$. The recoveries in fortified honey represented more than $70\%$ with low coefficient of variation $(<10\%)$ for concentration range of four tetracyclines. The detection limits for oxytetracycline, tetracycline, chlortetracycline and doxycycline were 13.8, 14.6, 26.2 and 24.9ng/g in acacia honey. respectively. We also monitored tetracyclines residue in domestic honey [n : 38, acacia (20), wild flower (18) ] and foreign honey [n=22, legally distributed (13), illegally distributed (9)] using modified Charm II screening and HPLC confirmation methods. Seven of the 60 samples $(11.7\%)$ were suspect positive using modified Charm II screening test. Chlortetracycline residue was found in one foreign honey (illegally distributed) tested at concentrations of 0.22 ppm. Conclusively, for more effective control of tetracyclines used in beekeeping should be further survey for residues in honey and also national guidelines (maximum residue limit : MRL) and methods should be obligatory.

$^{18}$F-Fluoride-PET in Skeletal Imaging ($^{18}$F-Fluoride-PET을 이용한 골격계 영상)

  • Jeon, Tae-Joo
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.4
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    • pp.253-258
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    • 2009
  • Bone scintigraphy using $^{99m}$Tc-labeled phosphate agents has long been the standard evaluation method for whole skeletal system. However, recent shortage of $^{99m}$Tc supply and advanced positron emission tomography (PET) technology evoked the attention to surrogate radiopharmaceuticals and imaging modalities for bone. Actually, fluorine-18 ($^{18}$F) was the first bone seeking radiotracer before the introduction of $^{99m}$Tc-labeled agents even though its clinical application failed to become pervasive anymore after the rapid spread of Anger type gamma camera systems in early 1970s. However, rapidly developed PET technology made us refocus on the usefulness of $^{18}$F as a PET tracer. Early study comparing $^{18}$F-Na PET scan and planar bone scintigraphy reported that PET has higher sensitivity and specificity in the diagnosis of metastatic bone lesions than planar bone scan. Subsequent reports comparing between PET and both planar and SPECT bone image also revealed better results of PET scan in similar study groups. Rapid clinical application of PET/CT also accumulated considerable amount of experiences in skeletal evaluation and this modality is known to have better diagnostic power than stand alone PET system as well as bone scan. Furthermore $^{18}$F-Na PET/CT revealed better or at least equal results in detection of primary and metastatic bone lesions compared with CT and MRI. Therefore, it is obvious that $^{18}$F-Na PET/CT has potential to become new imaging modality for practical skeletal evaluation so continuous and careful evaluation of this modality and radiopharmaceutical must be required.

A glucose biosensor based on deposition of glucose oxidase onto Au nanoparticles poly(maleic anhydride)-grafted multiwalled carbon nanotube electrode (금 나노입자/폴리(maleic anhydride) 그래프트 탄소나노튜브에 글루코스 옥시다아제 담지를 기반으로 한 글루코스 바이오센서)

  • Piao, Ming-Hua;Son, Pyeong-Soo;Chang, Choo-Hwan;Choi, Seong-Ho
    • Analytical Science and Technology
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    • v.23 no.2
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    • pp.165-171
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    • 2010
  • Glucose oxidase ($GOD_{ox}$) immobilized biosensor was fabricated by two methods. In one of the methods, gold nanoparticles (Au-NPs) prepared by ${\gamma}$-irradiation were loaded into the poly(maleic anhydride)-grafted multi-walled carbon nanotube, PMAn-g-MWCNT electrode via physical entrapment. In the other method, the Au-NPs were prepared by electrochemical reduction of Au ions on the surface of PMAn-g-MWCNT electrode and then GODox was immobilized into the Au-NPs. The $GOD_{ox}$ immobilized biosensors were tested for electrocatalytic activities to sense glucose. The sensing range of the biosensor based on the Au-NPs physically modified PMAn-g-MWCNT electrode was from $30\;{\mu}M$ to $100\;{\mu}M$ for the glucose concentration, and the detection limit was $15\;{\mu}M$. Interferences of ascorbic acid and uric acid were below 7.6%. The physically Au deposited PMAn-g-MWCNT paste electrodes appear to be good sensor in detecting glucose.

Microbial Quality and Physiochemical Changes of Grilled Fish Paste in a Group-Meal Service Affected by Gamma-Irradiation (감마선조사에 의해 영향을 받은 단체급식용 구운 어묵의 미생물학적 품질과 이화학적 변화)

  • Kim Jang-Ho;Jeon Jin-Yong;Ryu Sang-Ryeol;Kim Young-Ji;Suh Chung-Sik;Lee Ju-Woon;Byun Myung-Woo
    • Food Science and Preservation
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    • v.11 no.4
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    • pp.522-529
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    • 2004
  • In the grilled fish paste stored at $5^{\circ}C$, the total aerobic bacterial counts were effectively reduced by 2.5 kGy or more. In the samples stored at $30^{\circ}C$, the total aerobic bacterial counts of the samples irradiated at 7.5 kGy were below to the limit of detection (2 log CFU/g). The TBA values of the irradiated samples were considerably higher than those of the controls but not proportional to the irradiation dose. It is apparent that an irradiation treatment causes very little textural degradation and the sensorial quality of the sample was maintained by an irradiation at 7.5 kGy or more.

Qualitative and Quantitative Analysis of Dibenzocyclooctadiene Lignans for the Fruits of Korean "Omija" (Schisandra chinensis) (한국산 오미자로부터 디벤조사이클로옥타디엔 계열 리그난 화합물 정성 및 정량 분석)

  • Kim, Heon Woong;Shin, Jae Hyeong;Lee, Min Ki;Jang, Ga Hee;Lee, Sung Hyeon;Jang, Hwan Hee;Jeong, Seok Tae;Kim, Jung Bong
    • Korean Journal of Medicinal Crop Science
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    • v.23 no.5
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    • pp.385-394
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    • 2015
  • Background : Dibenzocyclooctadiene lignans are secondary metabolites present abundantly in the fruits belonging to the genus Schisandra. According to previous studies, Schisandra lignans exhibit anti-inflammatory, anti-cancer and anti-diabetic properties, as well as an inhibitory effect on platelet aggregation. Therefore, establishing the Korean "Omija" (Schisandra chinensis) as a lignan-rich source, in addition to identifying and quantifying the lignans, is extremely valuable. Methods and Results : Dibenzocyclooctadiene lignans were analyzed with liquid chromatography using diode array detection/mass spectrometry, from methanol extracts subsequently identified by a constructed chemical library of 50 lignans. A total of 27 components of lignan including gomisin S were identified, of which schisandrin, gomisin A, gomisin N, deoxyschisandrin, ${\gamma}$-schisandrin, and schisandrin C were identified as the major components in the Korean Omija, Schisandra chinensis. These compounds were divided into two groups, S-biphenyl and R-biphenyl based on the configurations of the stereoisomers structures with contents of 661.7 and 1350.1mg per 100 g dry weight, respectively. The total lignan content averaged 2011.4mg per 100 g dry weight, of which schisandrin and gomisin N comprised the majority (771.8 and 420.5mg per 100 g dry weight respectively). Conclusions : Lignans which are present in high quantities in the ripe fruit of Schisandra chinensis are important functional compounds that play a major role in the prevention and treatment of human diseases.

Complexation of Adiponectin-encoding Plasmid DNA with Rosiglitazone-loaded Cationic Liposomes

  • Davaa, Enkhzaya;Jeong, Ui-Hyeon;Shin, Baek-Ki;Choi, Soon-Gil;Myung, Chang-Seon;Park, Jeong-Sook
    • Journal of Pharmaceutical Investigation
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    • v.40 no.6
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    • pp.357-362
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    • 2010
  • To enhance therapeutic effects of insulin-sensitizing adipokine, ADN gene and potent agonists, rosiglitazone for the $PPAR{\gamma}$, cationic liposomes as non-viral vectors were formulated. The particle size and zeta potential of drug loaded and unloaded cationic liposomes were investigated. The complex formation between cationic liposomes and negatively charged plasmid DNA was confirmed and the protection from DNase was observed. In vitro transfection was investigated in HepG2, HeLa, and HEK293 cells by mRNA expression of ADN. Encapsulation efficacy of rosiglitazone-loaded liposomes was determined by UV detection. Particle sizes of cationic liposomes were in the range of 110-170 nm and those of rosiglitazone-loaded cationic liposomes were in the range of 130-180 nm, respectively. Gel retardation of complexes indicated that the complex was formed at weight ratios of cationic lipid to plasmid DNA higher than 20:1. Both complexes protected plasmid DNA from DNase either drug free or drug loading. Encapsulation efficiency of rosiglitazone-loaded emulsion was increased by drug dose. The mRNA expression levels of ADN were dose-dependently increased in cells transfected with plasmid DNA. Therefore, cationic liposomes could be potential co-delivery system for drug and gene.

Effect of Red Ginseng on Radiation-induced Learning and Memory Impairment in Mouse (방사선 조사 마우스에서 학습기억 장애에 대한 홍삼의 효과)

  • Lee, Hae-June;Kim, Joong-Sun;Moon, Chang-Jong;Kim, Jong-Choon;Jo, Sung-Kee;Jang, Jong-Sik;Kim, Sung-Ho
    • Journal of Ginseng Research
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    • v.33 no.2
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    • pp.132-138
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    • 2009
  • Previous studies suggest that even low-dose irradiation can lead to progressive cognitive decline and memory deficits, which implicates, in part, hippocampal dysfunction in both humans and experimental animals. In this study, whether red ginseng (RG) could attenuate memory impairment was investigated through a passive-avoidance and object recognition memory test, as well as the suppression of hippocampal neurogenesis, using the TUNEL assay and immunohistochemical detection with markers of neurogenesis (Ki-67 and doublecortin (DCX)) in adult mice treated with a relatively low-dose exposure to gamma radiation (0.5 or 2.0 Gy). RG was administered intraperitonially at a dosage of 50 mg/kg of body weight, at 36 and 12 h pre-irradiation and at 30 minutes post-irradiation, or orally at a dosage of 250 mg! kg of body weight/day for seven days before autopsy. In the passive-avoidance and object recognition memory test, the mice that were trained for one day after acute irradiation (2 Gy) showed significant memory deficits compared with the sham controls. The number of TUNEL-positive apoptotic nuclei in the dentate gyrus (DG) was increased 12 h after irradiation. In addition, the number of Ki-67- and DCX-positive cells was significantly decreased. RG treatment prior to irradiation attenuated the memory defect and blocked apoptotic death as well as a decrease in the Ki-67- and DCX-positive cells. RG may attenuate memory defect in a relatively low-dose exposure to radiation in adult mice, possibly by inhibiting the detrimental effect of irradiation on hippocampal neurogenesis.