• Title/Summary/Keyword: dose assessment

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Detection of Nitrate/Nitrite Bioavailability in Wastewater Using a luxCDABE-Based Klebsiella oxytoca Bioluminescent Bioreporter

  • Abd-El-Haleem, Desouky;Ripp, Steven;Zaki, Sahar;Sayler, Gary S.
    • Journal of Microbiology and Biotechnology
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    • v.17 no.8
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    • pp.1254-1261
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    • 2007
  • In the present study, we have constructed a bioluminescent bioreporter for the assessment of nitrate/nitrite bioavailability in wastewater. Specifically, an approximately 500-bp DNA fragment containing a nitrate/nitrite-activated nasR-like promoter (regulating expression of genes encoding nitrite reductase in the genus Klebsiella) was fused upstream of the Vibrio fischeri luxCDABE gene cassette in a modified mini-Tn5 vector. Characterization of this strain, designated W6-1, yielded dose-dependent increased bioluminescence coincident with increased nitrate, nitrite, and ammonium added to the growth medium from 1 to 11 ppm. Bioluminescence in response to nitrogen species addition was light dependent up to 10, 7, and 8 ppm with nitrate, nitrite, and ammonium, respectively. This response was linear in the range from 1 to 8 ppm for nitrate ($R^2=0.98$), 1 to 6 ppm for nitrite ($R^2=0.99$), and 1 to 7 ppm for ammonium ($R^2=0.99$). A significant bioluminescent response was also recorded when strain W6-1 was incubated with slurries from aged, nitrate/nitrite contaminated wastewater. Thus, bioreporter strain W6-1 can be used to elucidate factors that constrain the use of nitrate/nitrite in wastewaters.

Ozone Damage Assessment of Aspen at the Five Sites in Seoul Using a Computer Simulation Model of Individual Tree Growth, TREGRO

  • Yun, Sung-Chul;John A. Laurence;Park, Eun-Woo
    • The Plant Pathology Journal
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    • v.15 no.4
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    • pp.210-216
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    • 1999
  • TREGRO, a computer simulation model of individual tree growth, was applied to estimate ozone ($\textrm{O}_3$) effects on aspen(Populus tremuloides) growth under ambient and 1.7 times ambient $\textrm{O}_3$ of Seoul in 1996. The three highest $\textrm{O}_3$ (Kuui-dong, Ssangmun-dong, Sungsoo-dong) and the two lowest $\textrm{O}_3$ sites (Mapo-dong, Namgajwa-dong) were evaluated. The current ambient $\textrm{O}_3$ did not affect aspen growth compared to simulation without $\textrm{O}_3$. The only effect was 6.6 percent of total assimilated carbonloss at Ssangmun-dong where the level of $\textrm{O}_3$ was greatest among the 21 sites examined. Decrease as much as 50 percent of total carbon gain was calculated at 1.7 times ambient $\textrm{O}_3$ of the three highest sites. The carbon loss by $\textrm{O}_3$ came from biomass of tissues and total nonstructural cabron (TNC) such as starch and sugar. The most sensitive fraction was TNC and the next was root biomass. Foliage mass was not affected by $\textrm{O}_3$. Structural biomass loss was at best 1 to 3 percent at 1.7 times ambient $\textrm{O}_3$ at the two lowest sites. The daily carbon simulation was affected by $\textrm{O}_3$ mainly during Growth Period 4 (Jul. 21-Oct. 26). Correlations between site, dose, and the simulated responses of aspen (tissue biomass, TNC, respiration, and senescence) ranged from -0.703 to -0.973 depending on the plant responses. The ozone effects on poplar in Seoul are not severe currently, but are probably measurable at Ssangmun-dong. However, severe $\textrm{O}_3$ effects on biomass would occur if $\textrm{O}_3$ levels increase to 1.7 times ambient $\textrm{O}_3$ in Seoul. In addition, v could weaken the trees thus increasing susceptibility to pathogens or insects.

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Scintigraphic Assessment of Hepatobiliary Functions in Healthy Miniature Pigs (건강한 미니돼지에서 간담도 기능의 핵의학적 평가)

  • Kim, Se-Eun;Shim, Kyung-Mi;Yoo, Kyeong-Hoon;Lee, Won-Guk;Choi, Seok-Hwa;Park, Soo-Hyun;Han, Ho-Jae;Kang, Seong-Soo
    • Journal of Veterinary Clinics
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    • v.24 no.4
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    • pp.593-596
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    • 2007
  • The purpose of this study is to investigate normal hepatobiliary functions in healthy miniature pigs. $^{99m}Tc-DISIDA$ hepatobiliary scintigraphy(HBS) was used for it. Five mCi dose of $^{99m}Tc-DISIDA$ was injected intravenously into 3 healthy adult miniature pigs, and dynamic images were obtained during 1 hour. $^{99m}Tc-DISIDA$ HBS in a miniature pig was evaluated for 6 variables. A cardiac washout occurred within 1 min in all miniature pigs and radioactivities in the gallbladder were not detected in two miniature pigs. Thus, the initial radioactivity and Tmax of the gallbladder were non-available to identify. Mean Tmax of liver was $8.67{\pm}2.08$ min and initial small intestinal radioactivity was seen at $9.67{\pm}2.52$ min after $^{99m}Tc-DISIDA$ injection. Mean hepatic washout time was not detected in 60 min dynamic images. Therefore, $^{99m}Tc-DISIDA$ HBS is the effective diagnostic method to evaluate the function of hepatocyte and bile flow rate. However, it was not a proper method to evaluate the function of gallbladder, which indicates that an additional study is needed to further specify the reasons for the absence of radioactivities in gallbladder of two miniature pigs.

Assessment of Sensitivity of Photo-Chromosomal Assay in the Prediction of Photo-carcinogenicity (광염색체이상시험의 광발암성 예측능력에 대한 평가)

  • Hong Mi-Young;Kim Ji-Young;Lee Young Mi;Lee Michael
    • Toxicological Research
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    • v.21 no.2
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    • pp.99-105
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    • 2005
  • Photo-mutagenic compounds have been known to alter skin cancer rates by acting as initiators or by affecting subsequent steps in carcinogenesis. The objectives of this study are to investigate the utility of photo-chromosomal aberration (photo-CA) assay for detecting photo-clastogens, and to evaluate its ability to predict rodent photocarcinogenicity. Photo-CA assay was performed with five test substances that demonstrated positive results in photo-carcinogenicity tests: 8-Methoxypsoralen (photoactive substance that forms DNA adducts in the presence of ultraviolet A irradiation), chlorpromazine (an aliphatic phenothiazine an alpha-adrenergic blocking agent), lomefloxacin (an antibiotic in a class of drugs called fluoroquinolones), anthracene (a tricyclic aromatic hydrocarbon a basic substance for production of anthraquinone, dyes, pigments, insecticides, wood preservatives and coating materials) and Retinoic acid (a retinoid compound closely related to vitamin A). For the best discrimination between the test substance-mediated genotoxicity and the undesirable genotoxicity caused by direct DNA absorption, a UV dose-response of the cells in the absence of the test substances was firstly analyzed. All 5 test substances showed a positive outcome in photo-CA assay, indicating that the photo-CA test is very sensitive to the photo-genotoxic effect of UV irradiation. With this limited data-set, an investigation into the predictive value of this photo-CA test for determining the photo-carcinogenicity showed that photo-CA assay has the high ability of a test to predict carcinogenicity. Therefore, the photo-CA test using mammalian cells seems to be a sensitive method to evaluate the photo-carcinogenic potential of new compounds.

Levothyroxine Dose and Fracture Risk According to the Osteoporosis Status in Elderly Women

  • Ko, Young-Jin;Kim, Ji Young;Lee, Joongyub;Song, Hong-Ji;Kim, Ju-Young;Choi, Nam-Kyong;Park, Byung-Joo
    • Journal of Preventive Medicine and Public Health
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    • v.47 no.1
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    • pp.36-46
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    • 2014
  • Objectives: To evaluate the association between fracture risk and levothyroxine use in elderly women with hypothyroidism, according to previous osteoporosis history. Methods: We conducted a cohort study from the Korean Health Insurance Review and Assessment Service claims database from January 2005 to June 2006. The study population comprised women aged ${\geq}65$ years who had been diagnosed with hypothyroidism and prescribed levothyroxine monotherapy. We excluded patients who met any of the following criteria: previous fracture history, hyperthyroidism, thyroid cancer, or pituitary disorder; low levothyroxine adherence; or a follow-up period <90 days. We categorized the daily levothyroxine doses into 4 groups: ${\leq}50{\mu}g/d$, 51 to $100{\mu}g/d$, 101 to $150{\mu}g/d$, and > $150{\mu}g/d$. The hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated with the Cox proportional hazard model, and subgroup analyses were performed according to the osteoporosis history and osteoporosis-specific drug prescription status. Results: Among 11 155 cohort participants, 35.6% had previous histories of osteoporosis. The adjusted HR of fracture for the > $150{\mu}g/d$ group, compared with the 51 to $100{\mu}g/d$ group, was 1.56 (95% CI, 1.03 to 2.37) in osteoporosis subgroup. In the highly probable osteoporosis subgroup, restricted to patients who were concurrently prescribed osteoporosis-specific drugs, the adjusted HR of fracture for the > $150{\mu}g/d$ group, compared with the 51 to 100 ${\mu}g/d$ group, was 1.93 (95% CI, 1.14 to 3.26). Conclusions: While further studies are needed, physicians should be concerned about potential levothyroxine overtreatment in elderly osteoporosis patients.

Flumazenil administration in suspected patients with acute hypnotics and sedatives poisoning: risk-benefit re-evaluation (급성 진정제 중독 추정 환자에서 플루마제닐의 투여: 위험도/이익 재평가)

  • Huh, Jae Hong;Choi, Sang Chun;Lim, Yong Gyun;Lampotang, Samsun;Park, Eung Jung
    • Journal of The Korean Society of Clinical Toxicology
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    • v.14 no.2
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    • pp.92-99
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    • 2016
  • Purpose: The use of flumazenil administration in the emergency department is still controversial because of concerns about adverse effects. The present study was conducted to re-evaluate the risk-benefit ratio associated with flumazenil administration to patients suspected of having acute hypnotics and sedatives poisoning in the emergency department. Methods: A retrospective chart review study was conducted for patients whose final diagnoses were "poisoning" and "benzodiazepine" or "sedatives-hypnotics" from Mar. 2006 to Feb. 2015. The basal characteristics of the patients, including past medical history, ingredients and dose of ingested drug and co-ingested drugs were investigated. For patients administered flumazenil, responsiveness and time from admission to flumazenil administration were investigated with supplement. All collected data were analyzed in aspect terms of risk/benefit. Results: A total of 678 patients were included in our study. Benzodiazepine was the most common sedative/hypnotic drug prescribed, and the frequency of prescription continuously increased. The proportion of TCA as co-ingestion decreased from 13.1% to 3.9% in patients with acute sedative/hypnotic poisoning. Flumazenil was administered to 55 patients (8.1%), of which 29 patients (52.7%) were applied to contraindications. Fifty-three patients (96.4%) showed positive responsiveness, including partial responsiveness after flumazenil administration. No severe adverse events were identified. Conclusion: Based on the current trends in prescription patterns for sedative/hypnotic drugs, increased use of non-TCA antidepressants, and responsiveness to administration of flumazenil, benefit seemed weighted more in this study, although the observed benefits were based on limited results. Further prospective multicenter studies will be needed to optimize benefit-risk ratio.

Current Status of Intervention Studies on Acupuncture for Parkinson's Disease

  • Kim, Deok Hyun;Sin, Dae Chul;Song, Ho Sueb
    • Journal of Acupuncture Research
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    • v.34 no.3
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    • pp.13-21
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    • 2017
  • Objectives : The purpose of this study was to investigate the effect of acupuncture treatment (AT) in the tendency of increase of the need for AT for the treatment of Parkinson's disease (PD) worldwide and to investigate the advancements in AT research in Korea and the future directions of research on this topic. Methods : Until May 2017, the PubMed, Scopus, Medline, and four Korean databases were searched. The searched keywords were "Parkinson's disease", "Acupuncture", and "Intervention study". The intervention groups from all screened original studies were analyzed and the methods used to determine the effect of AT on PD were examined. Results : A total of 17 studies were grouped by country on the basis of the first author's position, of which 10 studies were conducted in China, four in the United States, two in Korea, and one in Brazil. The most common type of intervention was electroacupuncture (nine studies), followed by AT (six studies), and a combination of AT and bee venom AT (two studies). The most frequently used acupoints in AT were Baihui (GV20), Taichong (LR3), Zusanli (ST36), Sanyinjiao (SP6), and Yanglingquan (GB34). The most commonly used tool for evaluation of PD was the Unified Parkinson's Disease Rating Scale III, which assesses motor functions. Conclusion : The screened studies reported that there were no adverse effects of AT on drug therapy, and AT reduced the dose of drugs used in PD treatment. Future studies on PD treatment with AT should use the acupoints GV20, LR3, ST36, SP6, and GB34, and the meridians Gallbladder meridian and Governor Vessel. Clinical studies on PD should use CONSORT or STRICTA to ensure the quality of national studies and allow the development of new tools for the assessment of the effect of AT on PD using the above criteria.

Promotive Effects of Several Synthetic Hormones Using Short-Term Carcinogen Screening Method (단기 발암성 검색법을 이용한 축산식품에 잔류할 수 있는 합성홀몬의 발암촉진효과에 대한 연구)

  • 임윤규;강경선;이영순
    • Journal of Food Hygiene and Safety
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    • v.5 no.4
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    • pp.179-186
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    • 1990
  • This study was performed for assessing carcinogenicity of several synthetic hormones; Diethylstilbesterol (DES), 17-ethinylestradiol ($EE_2$) and Bovine somatotrophin (BST). Six weeks old F344 rats were divided into five groups and given an intraperitoneally injection of 200 mg of diethylnitrosamine (DENA). At two week after beginnig of experiment, DES, $EE_2$, BST. Phenobarbital were administered to group 1, 2, 3 and 4 respectively, group 4 is positive control and group 5 is negative control. At the same time, all groups received a single i.p. injection of D-galactosamine at a dose of 300 mg/kg and underwent 2/3 partial hepatectomy at week 5. All rats were sacrificed at the end of week 8 for assessment of liver lesion development. The liver was processed for immunohistochmical staining for GST-P and quantitatively analyzed by image analyzer. It was concluded that two synthetic estrogen hormones (DES, $EE_2$) was different significantly (p < 0.01) but BST was not different as compared with control group. Therefore, we thought that DES, $EE_2$ was promoting effects and BST was not in rat hepatocarcinogenesis.

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The Resolution of Amenorrhea in Female Patients Taking Risperidone (리스페리돈을 복용한 여성 환자에서 유발된 무월경의 치료)

  • Lee, Bun-Hee;Kim, Yong-Ku;Han, Chang-Su;Ko, Young-Hoon
    • Korean Journal of Biological Psychiatry
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    • v.10 no.2
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    • pp.141-146
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    • 2003
  • Objective:To find out the optimal assessment that can relieve amenorrhea associated with risperidone. Methods:Sixteen female outpatients who have taken risperidone for more than 3 months reported voluntarily amenorrhea during Nov 2001 to May 2002. Since the reports of the amenorrhea, the resolution of amenorrhea has been prospectively followed during the next six months. The dosage of risperidone was reduced or discontinued in nine of sixteen patients, while risperidone was switched to olanzapine or quetiapine in other 7 patients according to the clinician's decision. Results:Fourteen of 16 patients showed higher levels of prolactin than normal level. Five patients of the risperidone-reduction group recovered from the amenorrhea while all subjects of the drug-switch group recovered. The resolved patients of the former group recovered from amenorrhea in the dosage below 3mg per day of risperidone. Two patients of the risperidone-reduction group were dropped out during the reduction. Conclusion:These findings suggest that risperidone-induced amenorrhea may be alleviated by reducing dosage to less 3mg per day(including discontinuation) or by switching to other antipsychotic drugs. Whether we would choose which method depends on patient's clinical status, diagnosis, and dose of medication and so on.

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Twenty-Eight-Day Repeated Inhalation Toxicity Study of Aluminum Oxide Nanoparticles in Male Sprague-Dawley Rats

  • Kim, Yong-Soon;Chung, Yong-Hyun;Seo, Dong-Seok;Choi, Hyun-Sung;Lim, Cheol-Hong
    • Toxicological Research
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    • v.34 no.4
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    • pp.343-354
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    • 2018
  • Aluminum oxide nanoparticles ($Al_2O_3$ NPs) are among the most widely used nanomaterials; however, relatively little information about their risk identification and assessment is available. In the present study, we aimed to investigate the potential toxicity of $Al_2O_3$ NPs following repeated inhalation exposure in male Sprague-Dawley rats. Rats were exposed to $Al_2O_3$ NPs for 28 days (5 days/week) at doses of 0, 0.2, 1, and $5mg/m^3$ using a nose-only inhalation system. During the experimental period, we evaluated the clinical signs, body weight change, hematological and serum biochemical parameters, necropsy findings, organ weight, and histopathology findings. Additionally, we analyzed the bronchoalveolar lavage fluid (BALF), including differential leukocyte counts, and aluminum contents in the major organs and blood. Aluminum contents were the highest in lung tissues and showed a dose-dependent relationship in the exposure group. Histopathology showed alveolar macrophage accumulation in the lungs of rats in the $5mg/m^3$ group during exposure and recovery. These changes tended to increase at the end of the recovery period. In the BALF analysis, total cell and neutrophil counts and lactate dehydrogenase, tumor necrosis factor-${\alpha}$, and interleukin-6 levels significantly increased in the 1 and $5mg/m^3$ groups during exposure. Under the present experimental conditions, we suggested that the no-observed-adverse-effect level of $Al_2O_3$ NPs in male rats was $1mg/m^3$, and the target organ was the lung.