• Title/Summary/Keyword: PTU

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Pre-validation of the OECD Enhanced Test Guideline 407 Protocol on Screening and Testing for Endocrine Disrupters (Propylthiouracil을 이용한 OECD enhanced TG407의 내분비계 장애 물질검색을 위한 유효화 실험)

  • 강경선;김대용;제정환;김태원;김형섭;박지은;윤준원;김경배;이지해
    • Toxicological Research
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    • v.17 no.3
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    • pp.203-213
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    • 2001
  • We investigated the toxic effects of propylthiouracil (PTU) In Sprague-Dawley (SD) rats to develop and validate an enhanced Protocol for Test Guideline 407 as OECD Project. Twenty male and female SD rats,7 weeks old, were treated with PTU in corn oil at levels of 0, 0.1, 1 and 10 mg/kg/day for 4 weeks orally. Clinical observation, body weight changes, food uptake, water consumption, urinalysis, estrus cycle and sperm analysis, serum chemist교, autopsy findings and histopathological findings were evaluated in this study. No clinical signs and mortality were observed in the study. The body weights and food uptakes in the group treated with 10 mg/kg/day were reduced from 3 weeks after the initiation of the treatment. The levels of 3,5,3'-triiodothyronine (T3) and thyroxine (T4, 3,5,3',5'-tetraiodothyrosine) were also significantly decreased in the group treated with 10 mg/kg/day. Also, the relative and absolute organ weights of thymuses were decreased. Thyroid glands of rats in the group treated with PTU 10 mg/kg/day were bigger than those of rats in the control group. In the histopathological examination, diffuse hyperplasia and hypertrophy of thyroid follicular cells were observed in all treatment groups, leading to the reduction of lumen size and papillary enfolding of lining epithelium. The degree of lesion was increased in a dose-dependent manner. The results suggested that PTU would cause toxicity in thyroid gland and decrease the levels of T3 and T4 in SD rats. However there were no effects on the other organ including testis and uterus especially in spermatogenesis and estrus cycle. On the basis of the results, enhanced protocol for Test Guideline (TG) 407 may be sensitive and reliable to detect endocrine-active substances like PTU.

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Comparison of canal transportation in simulated curved canals prepared with ProTaper Universal and ProTaper Gold systems

  • Silva, Emmanuel Joao Nogueira Leal;Muniz, Brenda Leite;Pires, Frederico;Belladonna, Felipe Goncalves;Neves, Aline Almeida;Souza, Erick Miranda;De-Deus, Gustavo
    • Restorative Dentistry and Endodontics
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    • v.41 no.1
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    • pp.1-5
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    • 2016
  • Objectives: The purpose of this study was to assess the ability of ProTaper Gold (PTG, Dentsply Maillefer) in maintaining the original profile of root canal anatomy. For that, ProTaper Universal (PTU, Dentsply Maillefer) was used as reference techniques for comparison. Materials and Methods: Twenty simulated curved canals manufactured in clear resin blocks were randomly assigned to 2 groups (n = 10) according to the system used for canal instrumentation: PTU and PTG groups, upto F2 files (25/0.08). Color stereomicroscopic images from each block were taken exactly at the same position before and after instrumentation. All image processing and data analysis were performed with an open source program (FIJI). Evaluation of canal transportation was obtained for two independent canal regions: straight and curved levels. Student's t test was used with a cut-off for significance set at ${\alpha}=5%$. Results: Instrumentation systems significantly influenced canal transportation (p < 0.0001). A significant interaction between instrumentation system and root canal level (p < 0.0001) was found. PTU and PTG systems produced similar canal transportation at the straight part, while PTG system resulted in lower canal transportation than PTU system at the curved part. Canal transportation was higher at the curved canal portion (p < 0.0001). Conclusions: PTG system produced overall less canal transportation in the curved portion when compared to PTU system.

The Effects of Zingiberis rhizoma on Hypothyroidism Rat induced by PTU (건동(乾童)이 PTU로 유발된 Rat의 갑상선 기능저하증에 미치는 영향)

  • Kang, Ki-Hoon;Lee, Byung-Cheol;Ahn, Se-Young;Doo, Ho-Kyung;Ahn, Young-Min
    • The Journal of Internal Korean Medicine
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    • v.27 no.3
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    • pp.677-687
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    • 2006
  • Objective : Hypothyroidism is a common disease of the endocrinal system. characterized by fatigue, cold intolerance, bradycardia, and so on. Clinically, Levothyroxine(L-T4) has been usually used for replacement therapy, but it often has side effects. so many hypothyroidism patients wants oriental medical therapy. Zingiberis rhizoma, traditionally has been used in treatment of coldness, fatigue, and bradycardia. In this study. I investigated the therapeutic effects of Zingiberis rhizoma on PTU induced hypothyroidism in rats. Methods : I used two-month-old rats administered PTU and induced with hypothyroidism. After 2 weeks. Zingiberis rhizoma and thyroxine were daily administered, respectively. Body weights was measured every weeks. After 4 weeks, blood samples were taken and analyzed biochemically and T4 and TSH were measured by ELISA kits. Results : In comparison with normal groups, control groups showed hypothyroidism with low T4 and high TSH level. In Zingibris rhizoma administration groups were observed T4 level elevation, this elevation was dependent on the dose of Zingibris rhizoma. Between experimental groups and control groups, there was no difference in TSH level, statistically. Changes of biochemistry were not observed in any experimental groups. Conclusions : These findings suggest that Zingiberis rhizoma makes thyroid cells producing thyroid hormones. There is also a non-toxic effect on the cardiovascular system, liver and kidney function. So, Zingiberis rhizoma should be an effective agents for treating hypothyroidism.

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Effect of Low-level Laser Therapy on Propylthiouracil-induced Hypothyroidism Model Mice: A Pilot Study

  • Mun, In Kwon;Yoo, Won Sang;Lee, Sang Joon;Chung, Phil-Sang;Woo, Seung Hoon
    • Medical Lasers
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    • v.10 no.1
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    • pp.37-44
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    • 2021
  • Background and Objectives Hypothyroidism is the most common endocrine disease. On the other hand, there is no treatment that can improve the thyroid function. Low-level laser therapy (LLLT) can improve the cellular activity. The effect of hypothyroidism is not obvious. This study examined the effects of LLLT on the thyroid gland function of a propylthiouracil (PTU)-induced hypothyroidism mouse model. Materials and Methods Twenty-five male ICR mice were distributed into five groups of five animals each: Negative control (none PTU animal) and positive control (PTU animal) of unirradiated animals, and three experimental groups with LLLT (3J, 6J, and 12J). Each mouse was exposed to a distinct dose of a 632-nm laser once a week for three rounds. The positive control group and three LLLT groups were induced into a hypothyroidism state by PTU administration. The animals' thyroid-stimulating hormone and thyroxine levels were measured using an ELISA kit, and their thyroid tissue was harvested and analyzed after sacrifice at the end of the experiment. The hormone level and morphological changes in the tissue of the five groups were compared. Results The thyroid hormone levels in the control group and LLLT groups were similar. On the other hand, the thyroid tissue of the LLLT groups showed some morphological changes that were similar to those of iodine deficiency thyroid. Conclusion LLLT did not affect the thyroid gland function in PTU-induced hypothyroidism mice.

Effects of Propylthiouracil and Thyroxine on Thyroid Function and Body Growth in Rats (Propylthiouracil 및 Thyroxine의 처리(處理)가 흰쥐의 갑상선기능(甲狀腺機能)과 체성장(體成長)에 미치는 영향(影響))

  • Seo, Kil Woong;Lee, Kyu Seung;Park, Chang Sik
    • Korean Journal of Agricultural Science
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    • v.13 no.2
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    • pp.210-218
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    • 1986
  • This study was conducted to find out the effects of propylthiouracil and thyroxine on thyroid function and body growth in female rats. One hundred and forty-four female rats (Wistar-imamichi albino rats) of 25 days old were divided into 4 groups; thyroidectomy (Thx), propylthiouracil (PTU), thyroxine (Thyro.)and control (Cont.) groups. Thirty-six rats were allotted to each group, and changes of body weights were weekly checked. In addition, 6 rats in each group were sacrificed at 1, 2, 3, 5 and 6 weeks after treatments with time elapse for investigating changes of thyroid weights and tissues. The results obtained were as follows: 1. The weights of thyroid gland showed significant differences among all the compared groups at all observation times. The weights of thyroid glands in PTU group were higher than those in control group, but those in the Thyro. group were lower than those in control group. 2. In the histological changes of thyroid glands in the PTU group, the follicle epithelium showed columnar cells following hype trophy and hyperplasia from 1 week after treatment. The follicle epithelium in the Thyro. group were recognized inactive showing squamous cells. 3. The body weights showed significant differences among the compared groups from 2 weeks after treatment. The body weights decreased significantly in PTU and Thx. groups, while those in Thyro. group increased significantly in comparison with those in control group. No significant difference in body weight was noted between PTU and Thx. groups.

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A Case of Propylthiouracil Induced Diffuse Pulmonary Hemorrhage (Propylthiouracil 약제 복용으로 유발된 미만성 폐출혈 1예)

  • Lee, Sung Yong;Jung, Jin Yong;Lee, Kyoung Ju;Lee, Seung Hyeun;Kim, Se Joong;Lee, Eun Joo;Hur, Gyu Young;Jung, Hae Chul;Lee, Sang Yeub;Kim, Je Hyeong;Shin, Chol;Shim, Jae Jeong;In, Kwang Ho;Kang, Kyung Ho;Yoo, Se Hwa
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.1
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    • pp.78-82
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    • 2005
  • Propylthiouracil(PUT) is a drug which used at Grave's disease. But PTU has recently been observed to associated with antineutrophil cytoplasmic antibody(ANCA)-positive vasculitis resulting in, infrequently, diffuse alveolar hemorrhage. We report the case of a patient who developed diffuse pulmonary hemorrhage after she had been taking PTU for two years. She had received a diagnosis of Grave's disease at two years ago. The serologic study was positive for ANCA with myeloperoxidase(MPO) specificity. Bronchoalveloar lavage(BAL) fluid analysis revealed hemosiderinladen macrophages. Such findings suggested propylthiouracil-induced dffuse pulmonary hemorrhage associated with antineutrophil cytoplasmic antibody. To our knowledge, this represents the first documentation in a case of PTU-induced diffuse pulmonary hemorrhage in Korea.

The effects of autoclave sterilization on the cyclic fatigue resistance of ProTaper Universal, ProTaper Next, and ProTaper Gold nickel-titanium instruments

  • Ozyurek, Taha;Yilmaz, Koray;Uslu, Gulsah
    • Restorative Dentistry and Endodontics
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    • v.42 no.4
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    • pp.301-308
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    • 2017
  • Objectives: It was aimed to compare the cyclic fatigue resistances of ProTaper Universal (PTU), ProTaper Next (PTN), and ProTaper Gold (PTG) and the effects of sterilization by autoclave on the cyclic fatigue life of nickel-titanium (NiTi) instruments. Materials and Methods: Eighty PTU, 80 PTN, and 80 PTG were included to the present study. Files were tested in a simulated canal. Each brand of the NiTi files were divided into 4 subgroups: group 1, as received condition; group 2, pre-sterilized instruments exposed to 10 times sterilization by autoclave; group 3, instruments tested were sterilized after being exposed to 25%, 50%, and 75% of the mean cycles to failure, then cycled fatigue test was performed; group 4, instruments exposed to the same experiment with group 3 without sterilization. The number of cycles to failure (NCF) was calculated. The data was statistically analyzed by using one-way analysis of variance and post hoc Tukey tests. Results: PTG showed significantly higher NCF than PTU and PTN in group 1 (p < 0.05). Sterilization significantly increased the NCF of PTN and PTG (p < 0.05) in group 2. PTN in group 3 had significantly higher cyclic fatigue resistance than PTN group 4 (p < 0.05). Also, significantly higher NCF was observed for PTG in group 2 than in groups 3 and 4 (p < 0.05). Conclusions: PTG instrument made of new gold alloy was more resistant to fatigue failure than PTN and PTU. Autoclaving increased the cyclic fatigue resistances of PTN and PTG.

Preference of undergraduate students after first experience on nickel-titanium endodontic instruments

  • Kwak, Sang Won;Cheung, Gary Shun-Pan;Ha, Jung-Hong;Kim, Sung Kyo;Lee, Hyojin;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.41 no.3
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    • pp.176-181
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    • 2016
  • Objectives: This study aimed to compare two nickel-titanium systems (rotary vs. reciprocating) for their acceptance by undergraduate students who experienced nickel-titanium (NiTi) instruments for the first time. Materials and Methods: Eighty-one sophomore dental students were first taught on manual root canal preparation with stainless-steel files. After that, they were instructed on the use of ProTaper Universal system (PTU, Dentsply Maillefer), then the WaveOne (WO, Dentsply Maillefer). They practiced with each system on 2 extracted molars, before using those files to shape the buccal or mesial canals of additional first molars. A questionnaire was completed after using each file system, seeking students' perception about 'Ease of use', 'Flexibility', 'Cutting-efficiency', 'Screwing-effect', 'Feeling-safety', and 'Instrumentation-time' of the NiTi files, relative to stainless-steel instrumentation, on a 5-point Likert-type scale. They were also requested to indicate their preference between the two systems. Data was compared between groups using t-test, and with Chi-square test for correlation of each perception value with the preferred choice (p = 0.05). Results: Among the 81 students, 55 indicated their preferred file system as WO and 22 as PTU. All scores were greater than 4 (better) for both systems, compared with stainless-steel files, except for 'Screwing-effect' for PTU. The scores for WO in the categories of 'Flexibility', 'Screwing-effect', and 'Feeling-safety' were significantly higher scores than those of PTU. A significant association between the 'Screwing-effect' and students' preference for WO was observed. Conclusions: Novice operators preferred nickel-titanium instruments to stainless-steel, and majority of them opted for reciprocating file instead of continuous rotating system.

Protective Effects of Blue Honeysuckle on Rat Hypothyroidism Induced by Propylthiouracil

  • Lee, Woo-Yeol;Yi, Seong-Joon;Yun, Sungho;Lim, Mee-Kyung;Lee, Keun-Woo
    • Journal of Veterinary Clinics
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    • v.33 no.5
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    • pp.246-254
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    • 2016
  • The objective of the present study is to determine whether blue honeysuckle lyophilized concentrated powder (BH) has favorable effects on hypothyroidism and related reproductive organ damage. Hypothyroidism was induced by 9 subcutaneous administration of propylthiouracil (PTU) for 28 days. Levothyroxine (LT4)-treated group was intraperitoneally injected with LT4 for the same period, while for BH (125, 250, and 500 mg/kg) or Flos Lonicerae lyophilized aqueous extract (LF, 250 mg/kg)-treated groups, the test materials were orally administrated for 42 days: two weeks before PTU injection and during PTU administration. The changes in serum thyroid hormone levels, serum male sex hormone levels, and testis antioxidant defense system were observed by histopathology of the thyroid gland, epididymis, prostate, and testis. The oral administrations of 125, 250, and 500 mg/kg of BH showed favorable effects compared to LF on hypothyroidism and related damages of reproductive organs through augmentation of the antioxidant defense system in the testis. In conclusion, BH is a promising new potent thyroid gland protecting agent.

Quayside Container Crane Efficiency in the United States

  • Desrosiers, Robert A.
    • Journal of the Korean Institute of Navigation
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    • v.22 no.3
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    • pp.51-63
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    • 1998
  • This paper presents the results of a study that looks into the different operating structures of terminals in the United States and attempts to find the type of terminal management scheme (All-Comers Common User Facilities, Programmed Common User Facilities, and Program-Tied User Facilities) that is most efficient with regard to crane usage. The paper uses gross and net crane moves per hour to develop an efficiency ratio that is then used to compare terminals. A total of thirty-one terminals were compared in an attempted to find the most efficient management scheme. While the hypothesis that Program-Tied User Facilities are the most efficient operating scheme was accepted, the sample was too small to provide conclusive results pertinent to the terminals in the United States.

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