• Title/Summary/Keyword: selective exposure

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Protection of Primary Cultured Mouse Hepatocytes from Chemical Hypoxia-induced Injury by Hydrogen Sulfide (화학적 허혈에 의해 손상된 마우스 간세포에 대한 hydrogen sulfide의 간세포 보호 효과)

  • Lee, Min Young
    • Journal of Life Science
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    • v.23 no.11
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    • pp.1342-1350
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    • 2013
  • We examined the effect of hydrogen sulfide ($H_2S$) in chemical hypoxia-induced injury in mouse hepatocytes. Cell viability was significantly decreased by cobalt chloride ($CoCl_2$), a well-known hypoxia mimetic agent in a time- and dose- dependent manner. Sodium hydrosulfide (NaHS, a donor of $H_2S$) pretreatment before exposure to $CoCl_2$ significantly attenuated the $CoCl_2$-induced decrease of cell viability. $CoCl_2$ treatment resulted in an increase of intracellular ROS generation, which is inhibited by NaHS or N-acetyl-cysteine (NAC, a ROS scavenger), and p38 MAPK phosphorylation, which is also blocked by NaHS or NAC. The $CoCl_2$-induced increase of the Bax/Bcl-2 ratio was attenuated by NaHS, NAC, and SB 203580 (p38 MAPK inhibitor). The $CoCl_2$-induced decrease of cell viability was also attenuated by NaHS, NAC, and SB 203580 pretreatment. Additionally, NaHS inhibited the $CoCl_2$-induced COX-2. Similar to the effect of NaHS, NAC blocked $CoCl_2$-induced COX-2 expression. Furthermore, NS-398 (a selective COX-2 inhibitor) attenuated not only the $CoCl_2$-induced increase of the Bax/Bcl-2 ratio, it also decreased cell viability. Taken together, $H_2S$ protects primary cultured mouse hepatocytes against $CoCl_2$-induced cell injury through inhibition of the ROS-activated p38 MAPK cascade and the COX-2 pathway.

Ultrasound-Guided Injections in the Lumbar and Sacral Spine (요추 및 천추부에 대한 초음파 유도하 중재 시술)

  • Ko, Kwang Pyo;Song, Jae Hwang;Kim, Whoan Jeang;Kim, Sang Bum;Min, Young Ki
    • Journal of Korean Society of Spine Surgery
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    • v.25 no.4
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    • pp.185-195
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    • 2018
  • Study Design: Literature review. Objective: Ultrasound-guided injections are a common clinical treatment for lower lumbosacral pain that are usually performed before surgical treatment if conservative treatment fails. The aim of this article was to review ultrasound-guided injections in the lumbar and sacral spine. Summary of Literature Review: Ultrasound-guided injections, unlike conventional interventions using computed tomography or C-arm fluoroscopy, can be performed under simultaneous observation of muscles, ligaments, vessels, and nerves. Additionally, they have no radiation exposure and do not require a large space for the installation of equipment, so they are increasingly selected as an alternative method. Materials and Methods: We searched for and reviewed studies related to the use of ultrasound-guided injections in the lumbar and sacral spine. Results: In order to perform accurate ultrasound-guided injections, it is necessary to understand the patient's posture during the intervention, the relevant anatomy, and normal and abnormal ultrasonographic findings. Facet joint intra-articular injections, medial branch block, epidural block, selective nerve root block, and sacroiliac joint injections can be effectively performed under ultrasound guidance. Conclusions: Ultrasound-guided injections in the lumbar and sacral spine are an efficient method for treating lumbosacral pain.

Fluoride content of bottled water available in South Korea (국내 시판 생수의 불소 이온농도 측정)

  • Kim, Ji-Soo;Nam, Yong-Tae;Kim, Se-Yeon;Jun, Eun-Joo;Kim, Jin-Bom;Jeong, Seung-Hwa
    • Journal of Korean Academy of Oral Health
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    • v.42 no.4
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    • pp.199-203
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    • 2018
  • Objectives: The market for bottled water is increasing steadily in South Korea. Bottled water contains several naturally occuring minerals, such as calcium, magnesium, sodium, and fluoride. Fluoride is proven to be effective in preventing dental caries. In South Korea, the maximum permissible concentration of fluoride is 2 ppm for bottled water and 1.5 ppm for tap water. The aim of this study was to investigate the fluoride content of different commercially available brands of bottled water in South Korea, and compare the measured fluoride concentration to the concentration written on the label of each brand of bottled water. Methods: Twenty-seven of the 59 different brands of bottled water produced in South Korea were investigated in this study. Three bottles of each brand were purchased from supermarkets, marts, and convenience stores in each region of Korea in August 2016. For each bottled water brand, the fluoride content was measured three times using a fluoride-ion selective electrode (Orion ionplus Fluoride Electrode 9609, Orion Research, USA). The calibration curve was generated using 0.2 and 2 ppm standard solutions, and confirmed using a 1 ppm standard solution. Results: The mean fluoride content of the 27 brands of bottled water was $0.374{\pm}0.332mg/L$ (range=0.040 to 1.172 mg/L). The fluoride content was labeled by the manufacturer, on each of the tested brands of bottled water. In eight brands, the labeled fluoride content differed from the experimental data. The minimum to maximum fluoride content measured from 10 brands showed a variation of 0.3 mg/L or more when compared to the labeled fluoride content. Conclusions: This study investigated the fluoride content of various brands of bottled water produced in South Korea and compared the measured fluoride levels with fluoride information on the bottle labels. To ensure that consumers are suitably informed regarding their exposure to fluoride, correct labelling of fluoride content in bottled water is important.

Relationship between the Thyroid Hormone and Viral Infections in Pregnancy (임신 중 바이러스성 감염요인과 갑상선 호르몬의 상관성)

  • Lim, Dong-Kyu;Park, Chang-Eun
    • Korean Journal of Clinical Laboratory Science
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    • v.54 no.1
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    • pp.28-37
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    • 2022
  • Pregnancy requires an important interpretation of thyroid function tests. The presence of anti-thyroid antibodies and viral infectious agents affect the health of both the fetus and the mother. Hence, a selective evaluation of thyroid function in pregnancy is required. This study is a retrospective cross-sectional survey to examine the correlation between thyroid hormones and viral infections during pregnancy. The results showed that the triiodothyronine (T3) decreased with increasing age, especially in the hepatitis C virus (HCV)-positive group (P<0.01). In addition, although negative for the human immunodeficiency virus (HIV), thyroxine (FT4) showed a significant increase in near-threshold or twin pregnant women (P<0.05). The thyroid stimulating hormone (TSH) was highly distributed at the age of 30, and there was no statistically significant correlation with other viral infection factors. In addition, as a result of dividing and analyzing the result of TSH by the quantiles, FT4 and T3 showed a positive correlation but showed a negative correlation with TSH (P<0.05). Therefore, the evaluation of prenatal thyroid screening during pregnancy and viral infection factors should reflect the time of pregnancy, exposure to infection, and the quantitative values. Adequate thyroid hormone and viral infections availability is important for an uncomplicated pregnancy and optimal fetal development.

Cytotoxicity of COX-2 Inhibitor (Nimesulide) in Non-small Cell Lung Cancer Cell Line (비소세포폐암 세포주에서 COX-2억제제(Nimesulide)의 세포독성)

  • Park Chan Beom;Jeon Hyun Woo;Jin Ung;Cho Kyu Do;Kim Chi Kyung;Wang Young-Pil
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.263-270
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    • 2005
  • In recent years, a combination of two demographic phenomena, an increased number of older people in the population and an increase in the incidence of lung cancer with age, has made it mandatory to develop therapeutic modalities with less toxicity for the treatment of inoperable elderly patients with lung cancer. Therefore, we investigated the correlation between COX-2 expression and cytotoxicity of Nimesulide, a specific COX-2 inhibitor. Material and Method: Immunohistochemical staining of COX-2 was performed. After exposure of Nimesulide, XTT analysis, FACS analysis and Hoechst staining were carried out. Result: COX-2 protein was expressed in non-treated A549 cells strongly, but not in H1299. Cytotoxicity of Nimesulide against A549 cell and H1299 cell were similar and $IC_{50}$ of Nimesulide in both cell lines were $70.9{\mu}M$ in A549 cell line and $56.5{\mu}M$ in H1299 cell line respectively. FACS analysis showed $G_0/G_1$ arrest in both cell lines and the S phase cell fraction was decreased. Morphologic assessment of apoptosis by Hoechst 33258 staining, many apoptotic cells were detected in both cell lines. Conclusion: Selective COX-2 inhibitor, Nimesulide, can inhibit the proliferation of non-small cell lung cancer cell lines in vitro. Inhibitory effect of Nimesulide are induction of apoptosis and $G_0/G_1$ arrest. There is no correlation between COX-2 expression and cytotoxicity of Nimesulide, a specific COX-2 inhibitor. Therefore, highly selective COX-2 inhibitors such as Nimesulide can be expected to lead to even greater efficacy of their use as adjuncts to various anticancer angents and radiation therapy for the treatment of high-risk patients.

Effects of Olanzapine on the Schedule-Induced Polydipsic Rats (Olanzapine이 백서의 Schedule-Induced Polydipsia에 미치는 영향)

  • Lee, Gi-Chul;Lee, Kyung-Kyu;Chang, Hwan-Il;Lee, Jung-Ho;Kim, Hyun-Woo;Ha, Jun-Myung;Jeong, Jae-Hyun;Jeong, Hong-Kyung
    • Korean Journal of Biological Psychiatry
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    • v.6 no.2
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    • pp.240-245
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    • 1999
  • Object : This study was designed to evaluate the effects of olanzapine on the schedule-induced polydipsia(SIP) which is one of animal model of obsessive-compulsive disorder in rats. We administered olanzapine as a serotonin and dopamine blocking agent, fluoxetine as a selective serotonin reuptake inhibitor, and haloperidol for the dopamine antagonist to rats which showed schedule-induced polydipsic behavior. Methods : Spraque-Dawley rats weighing 200-250gm were individually housed and maintained and allowed free access to water. The rats were placed on a restricted diet. To induce polydipsia, rats were placed in the cage where a pellet dispenser automatically dispensed 90mg pellets on a fixed-time 60 seconds(FT-60s) feeding schedule over 150 minute test session per day. Water was available at all times in the cage. After 4 weeks of daily exposure to the FT 60s feeding schedule, experimental rats met a predetermined criterion for polydipsic behavior(greater than 3 times of water per session on average). 5 groups of rats were administered olanzapine(3mg/kg, i.p), olanzapine(10mg/kg, i.p), fluoxetine(5mg/kg, i.p.), haloperidol(0.1mg/kg, i.p.), and vehicle(1cc/kg, i.p.) for 3 weeks. The rats were tested once a week to access schedule induced polydipsic behavior. Water bottles were weighed before and after the 150-minute test session. The chronic effects of administration of experimental drugs on schedule induced polydipsic behavior were analyzed with ANOVA and Scheffe test as a posthoc comparison. In order to measure water consumption in non-polydipsic food-deprived rats, a separate group of rats(N=8) were individually housed and given a single bolus(14.5gm) of food per day which maintained them at their average body weight. Results and Conclusion : The results were as follows ; 1) After 4 weeks of scheduled feeding procedure, the experimental group showed significant differences than the bolus control in the amount of water consumption as compared with their average water intakes for 4 weeks. At the same periods, there were no differences between the experimental group and the bolus control in the body weight. 2) The fluoxetine group showed significant decrease in the amount of water intake over the 3 weeks of drug treatment as compared with their average amount of polydipsic water intakes. The olanzapine 3mg group showed significant decrease in the amount of water intake at 3rd weeks of drug treatment as compared with their average amount of polydipsic water intakes. The olanzapine 10mg group showed significant decrease in the amount of water intake at 2nd and 3rd weeks of drug treatment as compared with their average amount of polydipsic water intakes. However, the haloperidol group and the vehicle control group showed no changes of amounts of water intake for 3 weeks of treatment as compared with their average amount of polydipsic water intakes. 3) The fluoxetine group showed significantly lower amounts of water intake than the haloperidol group at 2nd weeks of drug treatment. And also the fluoxetine group showed significantly lower amounts of water intake than the haloperidol group and the vehicle control at 3rd weeks of drug treatment. The olanzapine 3mg group and the olanzapine 10mg group showed significantly lower amounts of water intake than the haloperidol group and the vehicle control at 3rd weeks of drug treatment. Above findings suggest that the fixed time feeding procedure for schedule-induced polydipsia as an animal model of obsessive compulsive disorder was effective to the evaluation of pharmacological challenge study. The authors assume that the serotonin hypothesis and the serotonin-dopamine interaction hypothesis are preferred to the dopamine hypothesis in the biological etiology of obsessive-compulsive disorder.

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Blue-light Induces the Selective Cell Death of Photoreceptors in Mouse Retina (청색광에 의한 마우스 망막손상에서 선택적 광수용세포의 사멸)

  • Kang, Seo-young;Hong, Ji Eun;Choi, Eun jung;Lyu, Jungmook
    • Journal of Korean Ophthalmic Optics Society
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    • v.21 no.1
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    • pp.69-76
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    • 2016
  • Purpose: The study was conducted to determine that photoreceptors of mouse having pigment in RPE(retinal pigment epithelium) can be damaged by blue-light and apoptosis of specific cells among photoreceptors are induced by blue-light, and to assist the investigation of AMD(Age-related macular degeneration) mechanisms and development of AMD drugs. Methods: C57Black mice were injured by irradiating $2800{\pm}10lux$ of 463 nm LED for 6 hours after 24 hours dark adaptation and eyes were enucleated 1, 3, 7 days. Damage of retina induced by blue-light was determined by western blotting GFAP(Glial fibrillary acidic protein) expression. In the light-injured retina, cell death of photoreceptors was determined by TUNEL(Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay. ERK(Extracellular signal-regulated kinases), JNK, and SRC(sarcoma) expression were assessed by western blotting to determine regulated pathway. Blue light-injured retina were immunostained with antibodies against Opsin and Rhodopsin as markers of photoreceptors to compared the damage cone cells with rod cells. Results: After 1, 3 and 7 days from exposure to blue-light, thickness of retina was more decreased than control, and more decreased at nuclear layer than at outer plexiform layer and GFAP expression was increased day 1 after blue-light injured. While phosphorylated ERK and SRC protein expressions at day 1 were increased after blue-light injured, phosphorylated c-JUN was decreased. Fluorescence intensity analysis showed that markers of cone and rod cells were decreased after blue-light injured and Opsin was more decreased than Rhodopsin. Conclusions: The study suggests possibilities that the blue-light promotes retinal damage and causes apoptotic cell death via ERK and SRC pathway in mouse retina, and blue-light retinal damage is more induced cone cells apoptosis than rod cells directly.

Comparison of Acute Toxicity of Molinate on Two Aquatic Insects, Chironomus riparius and Cloeon dipterum in Different Larval Stages (2종의 수서곤충 Chironomus riparius와 Cloeon dipterum의 유충 성장단계별 molinate 급성독성 비교)

  • Kim, Byung-Seok;Park, Yoen-Ki;Hong, Soon-Sung;Yang, Yu-Jung;Park, Kyung-Hun;Joeng, Mi-Hye;Kim, Se-Ri;Park, Kyeong-Hun;Yeh, Wan-Hae;Kim, Doo-Ho;Hong, Moo-Ki;Ahn, Young-Joon;Shin, Jin-Sup
    • The Korean Journal of Pesticide Science
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    • v.13 no.4
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    • pp.256-261
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    • 2009
  • Molinate (S-ethyl hexahydro-1H-azepine-1-carbothioate), a selective, preemergence thiocarbamate herbicide used for grass weed control in rice fields, is being most widely used in Korea. This study was conducted to assess the comparative toxicity of molinate on two aquatic insects, Chironomus riparius and Cloeon dipterum in four larval stages. First-instar larvae of C. riparius appeared to be the most sensitive to acute exposure of molinate with a 48-h $EC_{50}$ of 7.8 mg/L, followed by third instar (48-h $EC_{50}\;=\;22.9\;mg/L$), second instar (48-h $EC_{50}\;=\;25.0\;mg/L$) and fourth instar (48-h $EC_{50}$ > 50 mg/L) larvae. Also, the sensitivity of the larvae of C. dipterum was presented as the same manner of the larvae of C. riparius. The youngest group of larvae of C. riparius appeared to be the most sensitive to molinate, with 96-h $EC_{50}$ values ranged from 14.3 to 24.1 mg/L. The authors assume that the young instar lavae of aquatic insects, Chironomus riparius and Cloeon dipterum are more sensitive to molinate. Also, the authors propose that Mayfly, Cloeon dipterum is well suited as a bioassay organism because it is one of the most vulnerable aquatic insects inhabiting agricultural ecosystem in Korea.