• Title/Summary/Keyword: 14-3-$3{\beta}$

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Biodistribution and Scintigraphy of Iodine-131-Iododeoxyadenosine in Rats Bearing Breast Cancer (흰쥐에서 Iodine-131-Iododeoxyadenosine의 생체분포 및 유방암 영상화에 관한 연구)

  • Kim, Seon-Gu;Kim, Chang-Guhn;Lee, Kang-Mo;Kim, Hye-Won;Min Byung-Cheol;Choi, See-Sung;Lee, Jong-Deuk;Yang, David J.;Kim, E. Edmund;Lee, Hyun-Chul;Won Jong-Jin
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.4
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    • pp.374-381
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    • 1998
  • Purpose: I-131 labeled (2'-deoxy-2'-iodo-${\beta}$-D-arabinofuranosyl) adenine (IAD) may be involved in DNA synthesis during active proliferation of tumor cells. We conducted this study to find out the biodistribution of IAD and it's feasibility for scintigraphic tumor imaging. Materials and Methods: Tosyl acetyl-adenosine was dissolved in acetonitrile, and I-131-NaI was added and heated to synthesize IAD. Female Fisher 344 rats innoculated with breast tumor cells were injected with 0.27 MBq of IAD. Rats were sacrificed at 0.5, 1, 2, 4, 24h and the % of injected dose per gram of tissue (%ID/g) was determined. For scintigraphy, rats bearing breast cancer were administered with 1.11 MBq of IAD and imaging was performed after 2 and 24h. Then, rat body was fixed and microtomized slice was placed on radiographic film for autoradiography. Results: %ID/g of tumor was 0.74 (0.5h),0.73 (1h), 0.55 (2h), 0.38 (4h), and 0.05 (24h), respectively. At 1h after injection, %ID/g of tumor was higher than that of heart (0.34), liver (0.42), spleen (0.47), kidney (0.69), muscle (0.14), bone (0.33) and intestine (0.51). However, %ID/g of tumor was lower than blood (1.06), lung (0.77), and thyroid (177.71). At 4h, %ID/g of tumor in comparison with other tissue did not change. Tumor contrast expressed by tumor to blood ratio was 0.69 and tumor to muscle ratio was 5.11 at 1h. However, these ratios did not improve through 24h. On autoradiogram and scintigraphy at 2 and 24 hour, the tumor was well visualized. Conclusion: This results suggest that IAD may have a potential for tumor scintigraphy. However, further work is needed to improve localization in tumor tissue.

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SCIATIC NERVE REGENERATION USING CALCIUM PHOSPHATE COATED CONDUIT AND BRAIN-DERIVED NEUROTROPHIC FACTOR GENE-TRANSFECTED SCHWANN CELL IN RAT (인회석 박막 피복 도관과 Brain-derived neurotrophic factor(BDNF) 유전자 이입 슈반세포를 이용한 백서 좌골신경 재생에 관한 연구)

  • Choi, Won-Jae;Ahn, Kang-Min;Hwang, Soon-Jeong;Choung, Pill-Hoon;Kim, Myung-Jin;Kim, Nam-Yeol;Yoo, Sang-Bae;Jahng, Jeong-Won;Kim, Hyun-Man;Kim, Joong-Soo;Kim, Yun-Hee;Kim, Soung-Min;Lee, Jong-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.31 no.3
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    • pp.199-218
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    • 2005
  • Purpose of Study: Peripheral nerve regeneration depends on neurotrophism of distal nerve stump, recovery potential of neuron, supporting cell like Schwann cell and neurotrophic factors such as BDNF. Peripheral nerve regeneration can be enhanced by the conduit which connects the both sides of transected nerve. The conduit maintains the effects of neurotrophism and BDNF produced by Schwann cells which can be made by gene therapy. In this study, we tried to enhance the peripheral nerve regeneration by using calcium phosphate coated porous conduit and BDNF-Adenovirus infected Schwann cells in sciatic nerve of rats. Materials and Methods: Microporous filter which permits the tissue fluid essential for nerve regeneration and does not permit infiltration of fibroblasts, was made into 2mm diameter and 17mm length conduit. Then it was coated with calcium phosphate to improve the Schwann cell adhesion and survival. The coated filter was evaluated by SEM examination and MTT assay. For effective allogenic Schwann cell culture, dorsal root ganglia of 1-day old rat were extracted and treated with enzyme and antimitotic Ara-C. Human BDNF cDNA was obtained from cDNA library and amplified using PCR. BDNF gene was inserted into adenovirus shuttle vector pAACCMVpARS in which E1 was deleted. We infected the BDNF-Ad into 293 human mammary kidney cell-line and obtained the virus plaque 2 days later. RT-PCR was performed to evaluate the secretion of BDNF in infected Schwann cells. To determine the most optimal m.o.i of BDNF-Ad, we infected the Schwann cells with LacZ adenovirus in 1, 20, 50, 75, 100, 250 m.o.i for 2 hours and stained with ${\beta}$-galactosidase. Rats(n=24) weighing around 300g were used. Total 14mm sciatic nerve defect was made and connected with calcium phosphate coated conduits. Schwann cells$(1{\times}10^6)$ or BDNF-Ad infected Schwann cells$(1{\times}10^6)$ were injected in conduit and only media(MEM) was injected in control group. Twelve weeks after surgery, degree of nerve regeneration was evaluated with gait analysis, electrophysiologic measurements and histomorphometric analysis. Results: 1. Microporous Millipore filter was effective conduit which permitted the adhesion of Schwann cells and inhibited the adhesion of fibroblast. We could enhance the Schwann cell adhesion and survival by coating Millipore filter with calcium phosphate. 2. Schwann cell culture technique using repeated treatment of Ara-C and GDNF was established. The mean number of Schwann cells obtained 1 and 2 weeks after the culture were $1.54{\pm}4.0{\times}10^6$ and $9.66{\pm}9.6{\times}10^6$. 3. The mRNA of BDNF in BDNF-Ad infected Schwann cells was detected using RT-PCR. In Schwann cell $0.69\;{\mu}g/{\mu}l$ of DNA was detected and in BDNF-Adenovirus transfected Schwann cell $0.795\;{\mu}g/{\mu}l$ of DNA was detected. The most effective infection concentration was determined by LacZ Adenovirus and 75 m.o.i was found the most optimal. Conclusion: BDNF-Ad transfected Schwann cells successfully regenerated the 14mm nerve gap which was connected with calcium phosphate coated Millipore filter. The BDNF-Ad group showed better results compared with Schwann cells only group and control group in aspect to sciatic function index, electrophysiologic measurements and histomorphometric analysis.

Effect of Wine Yeast, Temperature and Moisture Contents on Characteristics of Jeung-Pyun Batter (Wine Yeast와 온도 및 수분함량이 증편 반죽의 특성에 미치는 영향)

  • 유진현;한규홍
    • Culinary science and hospitality research
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    • v.8 no.3
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    • pp.309-321
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    • 2002
  • In this study, the characteristics of Jeung-pyun hatter were investigated by wine yeast. The processing conditions were optimized by physicochemical characterization including pH, volume, reduced sugar. The effect of yeast concentration, moisture content on the fermentation time and temperature were investigated in view of improving productivity. It was found that the volume was increased at maximum state when the fermentation was carried out at 35 $^{\circ}C$ with 0.1% yeast concentration 60% of moisture. The quality of Jeung-Pyun was most preferable in the condition of 0.1% wine yeast(Pasteur Red) for 8 hrs at 35$^{\circ}C$.

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Alcohol Intake in Relation to Cardiovascular Risk Factors among (Middle Age) South Korean Men (한국의 중년기 남성의 심혈관계 질환 위험요인과 음주섭취와의 관련성)

  • Park, Kyung-Min
    • Research in Community and Public Health Nursing
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    • v.9 no.1
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    • pp.232-241
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    • 1998
  • 음주습관과 심혈관계 질환 위험요인사이의 관련성을 파악하기 위하여, 1996년 한국 경북에 있는 도시지역 한 철강회사에서 40-50대(40-59세) 남자 근로자 3444명으로부터 공복시 혈액을 10m1 채취하여 혈청지질, 혈당, Uric acid를 측정하고 신장, 체중, 혈압(10-20분 휴식후 측정)과 EKG를 측정하였다. 과거병력, 현재 건강상태, 음주량과 기간 및 음주종류를 포함한 생활습관, 흡연량/일, 운동시간/주 등의 설문지를 작성하였다. 알콜 소비량은 양-빈도의 Index에 의해 측정되었다. 한국 중년 남자에 대한 음주량, 음주기간, 알콜종류등에 따른 심혈관계 질환의 위험요인 유무 정도를 알아보기 위해, 비음주자를 기준으로하여 비교대상군은 금주자와 음주량(2군) 등에 의해 3군으로 분류하였으며, 음주기간에 따른 심혈관계 질환의 위험요인 유무정도를 알아보기 위해 비음주자을 기준으로하여 비교 대상군은 금주자와 음주기간(4군)에 따라 5군으로 분류하였다. 알콜종류에 따른 심혈관계 질환의 위험요인 유무정도를 알아보기 위해 비음주자을 기준으로하여 비교 대상군은 금주자와 음주알콜종류(3군)에 따라 4군으로 분류하였다. 심혈관계 질환 위험요인은 기준되는 범주를 2개(Table 1)로 분류하여 2*2표를 이용하여 odds ratio(dummy variable로 처리), ${\beta}$-coefficient와 표준오차를 이용해서 신뢰구간(95% C.I.)을 구하여 유의성 검정을 하였다. 금주자의 정의는 과거 3달 이상 술을 마시지 않는 사람을 말한다. 연구 집단의 평균 연령은 $44.4{\pm}3.9$세 이며, 비음주자는 649명으로 18.9%, 금주자는 70명(2.0%)이며 음주자는 2725명(79.1%)이다. 음주자중 에타놀 섭취를 평균 100.5g/주(median) 미만인 군은 1239명으로 연구집단 3444명중 35.7%이며, 평균 100.5g/주(median) 이상 음주군은 1276명으로 44.5%이었다. 3444명중 1532명(44.5%) 이 맥주와 소주를 섞어서 마시는 사람이었다. 음주 양에서, 연령, 흡연 양, 흡연 기간, 운동, 음주기간, 알콜종류 등을 통제하여 logistic regression한 결과, 비음주자에 비해 중정도 음주자(${\ge}$100.5gm/week ethanol)의 확장기 혈압의 Odds ratio는 1.33배로 유의하게 높았다(P<0.05). 다른 요인들은 통계적으로 유의한 차이를 보이지 않았다. 알콜종류에서도 연령, 흡연 양, 흡연 기간, 운동, 음주양, 음주기간, 등을 통제한, 비음주자에 비해 맥주와 소주를 섞어 마시는 음주자의 확장기 혈압의 Odds ratio는 1.38배로 유의하게 높았다(P<0.01). 다른 요인들은 통계적으로 유의한 차이를 보이지 않았다. 반면에 음주 습관 중 음주기간에서는 연령, 흡연양, 흡연 기간, 운동, 음주양, 알콜종류 등을 통제한 logistic regression 분석 결과 유의한 차이를 보인 것은 없었다. 그러나 음주기간과 심혈관계 질환 위험요인중 수축기와 확장기 혈압과의 관계는 J 모양을 나타내었다 . 수축기 혈압의 금주자군은 비차비가 1.0보다 약간 낮고(Odds ratio=0.88) 음주기간이 2-10년인 군의 Odds ratio=1.14, 음주기간이 11-20 년인군의 Odds ratio =1.18, 21년 이상인 군의 Odds ratio=1.20로 비음주자의 odds ratio=1에 비해 점차적으로 위험이 높아졌다. 확장기 혈압의 금주자군은 비차비가 1.0보다 약간 낮고(Odds ratio=0.91), 음주기간이 1년 이하인 군의 Odds ratio=1.18, 음주기간이 2-10 년인 군의 Odds ratio=1.23, 음주기간이 11-20 년인 군의 Odds ratio=1.27, 21년 이상인 군의 Odds ratio=1.27로 비음주자의 odds ratio=1에 비해 점차적으로 위험이 높아졌다.

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Measurement of Specific Radioactivity for Clearance of Waste Contaminated with Re-186 for Medical Application (의료용 Re-186 오염폐기물의 규제해제를 위한 방사능측정)

  • Kim, Chang-Bum;Lee, Sang-Kyung;Jang, Seong-Joo;Kim, Jung-Min
    • Journal of radiological science and technology
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    • v.40 no.4
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    • pp.633-638
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    • 2017
  • The amount of radioactive waste has been rapidly increased with development of radiation treatment in medical field. Recently, it has been a common practice to use I-131 for thyroid cancer, F-18 for PET/CT and Tc-99m for diagnosis of nuclear medicine. All the wastes concerned have been disposed of by means of the self-disposal method, for example incineration, after storage enough to decay less than clearance level. IAEA proposed criteria for clearance level of waste which depends on the individual ($10{\mu}Sv/y$) and collective dose (1 man-Sv/y), and concentration of each nuclide (IAEA Safety Series No 111-P-1.1, 1992 and IAEA RS-G-1.7, 2004). In this study, specific radioactivity of radioactive waste contaminated with Re-186 was measured to confirm whether it meets the clearance level. Re-186 has long half life of 3.8 days relatively and emits beta and gamma radiation, therefore it can be applied in treatment and imaging purposes. The specific radioactivity of contaminated gloves weared by radiation workers was measured by MCA(Multi-channel Analyzer) which was calibrated by reference materials in accordance with the measuring procedure. As a result, comparison evaluation of decay storage period between the half-life which was calculated by attenuation curve based on real measurement and physical half-life was considered, and it is showed that the physical half-life is longer than induced half-life. Therefore, the storage period of radioactive waste for self-disposal may be curtailed in case of application of induced half-life. The result of this study will be proposed as ISO standard.

Analysis of Nutritional Components, Volatile Properties, and Sensory Attributes of Cynanchi wilfordii Radix: Characterization Study (백하수오의 식품학적 영양 성분 및 휘발성 향기 성분 분석을 통한 관능적 특성 검토)

  • Lim, Ho-Jeong;Kim, Jae-Kyeom;Cho, Kye Man;Joo, Ok Soo;Nam, Sang Hae;Lee, Shin-Woo;Kim, Hyun Joon;Shin, Eui-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.4
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    • pp.564-572
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    • 2015
  • Nutritional compositions, volatile compounds, and sensory attributes of Cynanchi wilfordii Radix were analyzed in order to examine its practical utilization as a food resource. In the proximate analysis, protein and lipid contents were shown to be 14.6 and 5.0 mg/100 g, respectively, in C. wilfordii Radix. Potassium was the most predominant mineral (809 mg/100 g), as determined by inductively coupled plasma-optical emission spectrometry in parallel with microwave acid digestion. Total phenolic content was found to be 410 mg/100 g. Further, arginine and linoleic acid were the most abundant amino acid and fatty acid of C. wilfordii Radix, respectively. To examine its functional properties, classical 2,2-diphenyl-1-picrylhydrazyl (DPPH) analysis was performed. As a result, the concentration of C. wilfordii Radix required to scavenge 50% of DPPH radicals was 1.16 mg of dried material. Lastly, in olfactory and sensory tests, ${\beta}$-eudesmol (woody odor) was the major flavor compound responsible for the bitter taste and sensory attributes of C. wilfordii Radix. Taken altogether, the above results provide important preliminary results for utilization of C. wilfordii Radix as a food resource.

Public Health Risks: Chemical and Antibiotic Residues - Review -

  • Lee, M.H.;Lee, H.J.;Ryu, P.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.3
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    • pp.402-413
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    • 2001
  • Food safety is a term broadly applied to food quality that may adversely affect human health. These include zoonotic diseases and acute and chronic effects of ingesting natural and human-made xenobiotics. There are two major areas of concern over the presence of residues of antibiotics in animal-derived foodstuffs with regard to human health. The first is allergic reactions. Some antibiotics, such as penicillins can evoke allergic reactions even though small amounts of them are ingested or exposed by parenteral routes. The second is development of antibiotic resistance in gut bacteria of human. Recently multi-resistant pneumococcal, glycopeptide-resistant enterococci and gram negative bacteria with extended-spectrum $\beta$-lactamases have spread all over the world, and are now a serious therapeutic problem in human. Although it is evident that drugs are required in the efficient production of meat, milk and eggs, their indiscriminate use should never be substituted for hygienic management of farm. Drug should be used only when they are required. In addition to veterinary drugs, environmental contaminants that were contaminated in feed, water and air can make residues in animal products. Mycotoxins, heavy metals, pesticides, herbicides and other chemicals derived from industries can be harmful both to animal and human health. Most of organic contaminants, such as dioxin, PCBs and DDT, and metals are persistent in environment and biological organisms and can be accumulated in fat and hard tissues. Some of them are suspected to have endocrine disrupting, carcinogenic, teratogenic, immunodepressive and nervous effects. The governmental agencies concerned make efforts to prevent residue problems; approval of drugs including withdrawal times of each preparation of drugs, establishment of tolerances, guidelines regarding drug use and sanitation enforcement of livestock products. National residue program is conducted to audit the status of the chemical residues in foods. Recently HACCP has been introduced to promote food safety from farm to table by reducing hazardous biological, chemical and physical factors. Animal Production Food Safety Program, Quality Assurance Programs, Food Animal Residue Avoidance Databank are para- or non-governmental activities ensuring food safety. This topic will cover classification and usage or sources of chemical residues, their adverse effects, and chemical residue status of some countries. Issues are expanded to residue detection methodologies, toxicological and pharmacokinetic backgrounds of MRL and withdrawal time establishments, and the importance of non-governmental activities with regard to reducing chemical residues in food.

Effects of dietary supplementation of lipid-coated zinc oxide on intestinal mucosal morphology and expression of the genes associated with growth and immune function in weanling pigs

  • Song, Young Min;Kim, Myeong Hyeon;Kim, Ha Na;Jang, Insurk;Han, Jeong Hee;Fontamillas, Giselle Ann;Lee, Chul Young;Park, Byung-Chul
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.3
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    • pp.403-409
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    • 2018
  • Objective: The present study was conducted to investigate the effects of a lipid-coated zinc oxide (ZnO) supplement Shield Zn (SZ) at the sub-pharmacological concentration on intestinal morphology and gene expression in weanling pigs, with an aim to gain insights into the mechanism of actions for SZ. Methods: Forty 22-day-old weanling pigs were fed a nursery diet supplemented with 100 or 2,500 mg Zn/kg with uncoated ZnO (negative control [NC] or positive control [PC], respectively), 100, 200, or 400 mg Zn/kg with SZ for 14 days and their intestinal tissues were taken for histological and molecular biological examinations. The villus height (VH) and crypt depth (CD) of the intestinal mucosa were measured microscopically following preparation of the tissue specimen; expression of the genes associated with growth and immune function was determined using the real-time quantitative polymerase chain reaction. Results: There was no difference in daily gain, gain:feed, and diarrhea score between the SZ group and either of NC and PC. The VH and VH:CD ratio were less for the SZ group vs NC in the jejunum and duodenum, respectively (p<0.05). The jejunal mucosal mRNA levels of insulin-like growth factor (IGF-I) and interleukin (IL)-10 regressed and tended to regress (p = 0.053) on the SZ concentration with a positive coefficient, respectively, whereas the IL-6 mRNA level regressed on the SZ concentration with a negative coefficient. The mRNA levels of IGF-I, zonula occludens protein-1, tumor necrosis $factor-{\alpha}$, IL-6, and IL-10 did not differ between the SZ group and either of NC and PC; the occludin and transforming growth $factor-{\beta}1$ mRNA levels were lower for the SZ group than for PC. Conclusion: The present results are interpreted to suggest that dietary ZnO provided by SZ may play a role in intestinal mucosal growth and immune function by modulating the expression of IGF-I, IL-6, and IL-10 genes.

Estimation of the Daily Human Intake of Acrylamide (AA) Based on Urinary N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA) and the Contribution of Dietary Habits in South Korean Adults (요중 AAMA에 의한 한국 성인 아크릴아마이드(AA)의 하루섭취량 추정 및 기여 식습관에 대한 분석)

  • LEE, Jin-Heon;LEE, Kee-Jae;KANG, Hee-Sook
    • Journal of Environmental Health Sciences
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    • v.42 no.4
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    • pp.235-245
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    • 2016
  • Objectives: This study estimated the adult Korean daily intake of acrylamide (AA) and investigated its relationship with demographic, lifestyle and dietary habits by using urinary concentrations of N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA). Methods: Human data (n=1870) was collected in a nationwide cross-sectional biomonitoring program representing the population (18-69 years) residing in South Korea. Urinary AAMA was analyzed with a LC-MS/MS system. Daily intakes of AA were estimated using mass daily AAMA, which was calculated through urinary AAMA concentration and daily creatinine excretion. Statistical analysis was performed with SAS procedures for calculating geometric means, confidence intervals and the exponentiated beta coefficient of multiple linear regressions. Results: Daily intake of AA was estimated at $0.475{\mu}g/kg$ body weight (BW) per day (95% confidence interval (CI): 0.447-0.503). In the case of current smokers, AA intake was $0.957{\mu}g/kg$ BW per day (95% CI: 0.847-1.067), which was significantly higher than that of former smokers and never smoked (p<0.0001). The strong affecting factors were age (95% CI: 0.68-1.14; p=0.0180), education level (95% CI: 1.05-1.42; p=0.0163), body mass index (BMI) (95% CI: 1.00-1.82; p<0.0001), and smoking status (95% CI: 0.97-3.05; p<0.0001). Korean dietary habits increasing AA intake were coffee (p=0.0005), cup noodles (p=0.0010) and canned foods (p=0.0005). Meanwhile, foods decreasing AA intake were fresh fruit (p=0.0076), cooked beef (p=0.0335) and cooked pork (p=0.0147). Conclusion: The Korean daily intake of AA in adults was estimated to be similar with those found in developed countries. The factors increasing daily AA intake were coffee, cup noodles and canned foods, and decreasing factors were fresh fruit, cooked beef and cooked pork.

Pharmacokinetics and Excretion into Expired Air of Urea, a Potential Diagnosis Reagent of Helicobacter pylori Infection (헬리코박터 파이로리 균의 진단시약 개발을 위한 요소의 체내동태 및 호기 중 배설)

  • Park, Seung-Hyeok;Shin, Dae-Hwan;Cho, Han-Jun;Yim, Ju-Bin;Lim, Sung-Cil;Han, Kun;Chung, Youn-Bok
    • Korean Journal of Clinical Pharmacy
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    • v.22 no.2
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    • pp.160-166
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    • 2012
  • Purpose: The purpose of the present study was to investigate the pharmacokinetics of urea, a new potential diagnosis reagent of Helicobacter pylori infection. Methods: Considering the mechanism of urea breath test, we determined the excretion of urea in expired air after its oral administration in rats and beagle dogs at the dose of 2 mg/kg (including 50 mCi/mmol $^{14}C$-urea 50 ${\mu}Ci/kg$ for rats and 13.5 ${\mu}Ci/kg$ for dogs). Results: Urea was rapidly disappeared from the blood circulation by 1 hr after its i.v. bolus injection, followed by a slow disappearance by 24 hr. The half-lives at the distributive phase ($t_{1/2{\alpha}}$) and post-distributive phase ($t_{1/2{\beta}}$) were 2 min and 6 hr, respectively. The bioavailability of urea was 64.3% after its oral administration. The values of the volume of distribution ($V_{dss}$) and the total body clearance ($CL_t$) after the oral administration were compatible with those after i.v. administration. The recovery of urea in the bile was about 0.1% of the dose by 24 hr after its oral administration. Urea was extensively eliminated in the urine by 48 hr. The recovery ratios of urea in the urine and expired air were about 86.8% and 2.99% of the dose by 48 hr, respectively. Moreover, urea was mostly distributed from the blood circulation to the kidney, followed by being eliminated in the urine without metabolism. The concentration of urea in the kidney was 4.0 times higher than that of plasma at 40 min after its oral administration. Conclusions: These findings indicated that oral route appears to be available for the administration of urea. Orally administered urea, thus, was considered to be useful for the diagnosis of Helicobacter pylori infection.