• Title/Summary/Keyword: Dose-response

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X-band EPR dosimetry using minimum mass of tooth enamel for use in radiological accidents

  • Jae Seok Kim;Byeong Ryong Park;Han Sung Kim;In Mo Eo;Jaeryong Yoo;Won Il Jang;Minsu Cho;HyoJin Kim;Yong Kyun Kim
    • Nuclear Engineering and Technology
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    • v.56 no.1
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    • pp.123-131
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    • 2024
  • Electron paramagnetic resonance (EPR) dosimetry for a tooth from an individual exposed is well known as retrospective dosimetry in radiological accidents. A major constraint of the conventional X-band tooth-EPR dosimetry is the necessity to extract the tooth of the exposed patient for dose assessment. In this study, to conduct the dose assessments of exposed patients through part-extraction of tooth enamel, the minimum detectable dose (MDD) of the tooth enamel was evaluated based on the amount of mass. Further, a field test was conducted via intercomparison using various dose assessment methods to verify the feasibility of X-band tooth-EPR dosimetry using the minimum mass of tooth enamel. The intercomparison results demonstrated that effective dose determination via X-band tooth-EPR dosimetry is reliable. Consequently, it was determined that the minimum mass of tooth enamel required to evaluate an absorbed dose above 0.5 Gy is 15 mg. Thus, EPR dosimetry using 15 mg of tooth enamel can be applied in the triage and initial medical response stages for patients exposed during radiological accidents. This approach represents an advancement in managing radiological accidents by offering a more efficient and less invasive method of dose assessment.

Effect of Cadmium Chloride on the Immune Responses in Balb/c Mouse (카드뮴투여가 Balb/c 마우스의 면역반응에 미치는 영향)

  • 염정호;강현철;고대하
    • Journal of Environmental Health Sciences
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    • v.21 no.3
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    • pp.16-22
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    • 1995
  • This study was designed to investigate the antibody production to sheep red blood cells(SRBC) and proliferation of mitogen-stimulated spleen cells in Balb/c mice which received cadmium chloride. The mice were divided into three independent groups which were one control and two experimental groups by the cadmium treatment or not. No specific treatment was done for the control group. One of two experimental groups, which is called 'pre-treatment group' in this paper, was subcutaneously injected with low dose of cadmium chloride(0.5 mg/kg/day) for 5 consecutive days before the primary SRBC immunization. The other called 'non-pretreatment group' was only pretreated with normal saline. Both experimental groups were intraperitoneally injected with high dose of cadmium chloride(5 mg/kg) 8 hours before the primary immunization. Mice were intraperitoneally immunized twice with 2% SRBC suspension containing $10^8$ cells. The results obtained were as follows, 1. The PFG responses to SRBC were significantly increased in two experimental groups, cadmium pretreatment and non-pretreatment compared with that of control group(p<0.05). 2. The total antibody titers to SRBC in cadmium treated groups were similar to that of control group, but titers of IgG antibody were significantly elevated(p<0.01). 3. The proliferation response of spleen lymphocytes to various mitogens was suppressed in proportion to the concentration of cadmium and the degree of cadmium accumulation in liver was increased in the cadmium treated groups. These results suggest that cadmium chloride could affect on mouse immune response, especially its cell mediated immune response could be decreased while its humoral immune response could be increased, which may not be influenced by the administration methods or pretreatment of cadmium to mouse.

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Effect of zinc on the immune response and production performance of broilers: a meta-analysis

  • Hidayat, Cecep;Sumiati, Sumiati;Jayanegara, Anuraga;Wina, Elizabeth
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.3
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    • pp.465-479
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    • 2020
  • Objective: This study performed a meta-analysis of published trials to determine the effects of zinc on the immune response and production performance of broilers. Methods: A database was built from published literature regarding the addition of zinc forms or doses and their relation to the immune response and production performance of broilers. Different doses or forms of zinc were identified in the database. The recorded parameters were related to the immune response and production performance. The database contained a total of 323 data points from 41 studies that met the criteria. Then, the data were processed for a meta-analysis using a mixed model methodology. The doses or different forms of zinc were considered fixed effects, different studies were treated as random effects, and p-values were used as the model statistics. Results: An increase in zinc dose increased (p<0.05) pancreas metallothionein (MT) and zinc concentrations in the plasma, tibia and meat, all in quadratic patterns, but linearly decreased (p<0.05) the heterophil/lymphocyte (H/L) ratio. Regarding the different zinc forms, both inorganic and organic zinc increased (p<0.05) the zinc concentrations in the plasma and tibia, the calcium and phosphorus contents in the tibia, and the antioxidant activity of superoxide dismutase in meat as compared to control. An increase in zinc dose increased average daily gain (ADG) and decreased feed conversion ratio (FCR) following a quadratic pattern (p<0.05). Inorganic and organic zinc decreased (p<0.05) FCR and H/L ratio than that of control, but these two forms were similar for these parameters. Conclusion: Zinc addition has a positive impact on immunity and broiler production. Zinc can suppress stress and inhibit the occurrence of lipid peroxidation in broilers, and it can also improve ADG, FCR, and the quality of broiler carcasses.

Application of Response Surface Method as an Experimental Design to Optimize Coagulation Tests

  • Trinh, Thuy Khanh;Kang, Lim-Seok
    • Environmental Engineering Research
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    • v.15 no.2
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    • pp.63-70
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    • 2010
  • In this study, the response surface method and experimental design were applied as an alternative to conventional methods for the optimization of coagulation tests. A central composite design, with 4 axial points, 4 factorial points and 5 replicates at the center point were used to build a model for predicting and optimizing the coagulation process. Mathematical model equations were derived by computer simulation programming with a least squares method using the Minitab 15 software. In these equations, the removal efficiencies of turbidity and total organic carbon (TOC) were expressed as second-order functions of two factors, such as alum dose and coagulation pH. Statistical checks (ANOVA table, $R^2$ and $R^2_{adj}$ value, model lack of fit test, and p value) indicated that the model was adequate for representing the experimental data. The p values showed that the quadratic effects of alum dose and coagulation pH were highly significant. In other words, these two factors had an important impact on the turbidity and TOC of treated water. To gain a better understanding of the two variables for optimal coagulation performance, the model was presented as both 3-D response surface and 2-D contour graphs. As a compromise for the simultaneously removal of maximum amounts of 92.5% turbidity and 39.5% TOC, the optimum conditions were found with 44 mg/L alum at pH 7.6. The predicted response from the model showed close agreement with the experimental data ($R^2$ values of 90.63% and 91.43% for turbidity removal and TOC removal, respectively), which demonstrates the effectiveness of this approach in achieving good predictions, while minimizing the number of experiments required.

Evaluation of function and disorders of the adrenal gland in neonates (신생아에서의 부신기능 평가와 질환)

  • Hwang, Il Tae
    • Clinical and Experimental Pediatrics
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    • v.50 no.3
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    • pp.236-240
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    • 2007
  • Majority of sick full term newborns have adequate adrenal cortical function in response to stress. Acutely ill neonates with a basal cortisol level less than $15{\mu}g/dL$ (414 nmol/L) suggest adrenal insufficiency and require function testing of adrenal function. In premature infant, immaturity of hypothalamic-pituitary adrenal axis (HPA axis), may limit the ability to increase cortisol production in response to stress. The response to low dose ACTH and CRH appears to be useful as an additional test of adrenal function. CRH stimulation has been used increasingly in neonates. The ACTH and CRH stimulated cortisol response of more than $17{\mu}g/dL$ (469 nmol/L) indicates a normal response.

Influence of Debrisoquine Pressor Actions of Norepinephrine and Tyramine in Rabbits (Debrisoquine이 노르에피네프린 및 티라민의 승압효과에 미치는 영향)

  • 고석태;김해석;이상현
    • YAKHAK HOEJI
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    • v.30 no.3
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    • pp.111-120
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    • 1986
  • The influence of debrisoquine on pressor actions of norepinephrine (NE) and tyramine (TR) was investigated in rabbits. Debrisquine(D), in the doses of 1.0, 3.0 and 6.0.mu.g/kg, i.v. potentiated significantly the pressor actions of NE and TR, except the action of TR in the dose of 1.0mg/kg of debrisoquine. NE response potentiated by debrisoquine was not affected by tranylcypromine, a MAO inhabiter, or desipramine, a NE uptake blocking agent, but augmented by reserpine, a NE depleting agent, or bethanidine, a sympathetic neuronal blocking agent. NE response potentiated by tranylcypromine or desipramine was augmented by debrisoquine, while NE response potentiated by reserine or bethanidine was not affected by debrisoquine. TR response potentiated by debrisoquine was weakened by tranylcypromine, desipramine or reserpine, and not affected by bethanidine. TR response in rabbit pretreated with tranylcypromine, desipramine or reserpine was augmented by debrisoquine, but in rabbit pretreated with bethanidine was not affected by debrisoquine.

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Quantitative Microbial Risk Assessment on Legionella Infection in Children Playing in Interactive Fountains (바닥분수에서 물놀이를 하는 아동들의 Legionella균 감염 위해도 분석)

  • Lee, In-Sup;Zo, Young-Gun
    • Korean Journal of Microbiology
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    • v.49 no.4
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    • pp.360-368
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    • 2013
  • Recently interactive water fountains are gaining popularity in making public facilities in South Korea. The total number of interactive fountains is rapidly growing at the rate of >50% annually. In this study, we performed quantitative microbial risk assessment to estimate infection risks in children by Legionella spp. while playing in interactive fountains. The exposure dose for a given concentration of Legionella in water was calculated using water-aerosol partition rate of Legionella, exposure duration, inhalation rate, and deposit rate of aerosols in the lungs following inhalation. The dose was converted to infection risk by using the dose-response function developed for L. pneumophila. High weight and/or old children, i.e., 12-year children, running around in fountains were the highest risk group by showing >0.05 infection probability for fountain waters containing ${\geq}10^4$ CFU/L Legionella. The result supported the current guideline by Korea Centers for Disease Control and Prevention, which permits use of water with < $10^3$ CFU/L Legionella cells for all purposes. However, the results still warrant further evaluation of the guideline to accommodate risks for children because the dose-response relationship in the model was developed for healthy adults. Further risk assessment studies need to be conducted by employing dose-response model for children who generally carries weaker immune system than adults.

Effects of Diuretics on Warfarin Responses in Patients with Atrial Fibrillation (심방세동 환자에서 Warfarin 반응성에 이뇨제가 미치는 영향)

  • Park, Hee Joo;La, Hyen-Oh;Gwak, Hye Sun
    • Korean Journal of Clinical Pharmacy
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    • v.23 no.2
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    • pp.151-157
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    • 2013
  • Purpose: Warfarin is the most widely used anticoagulant drug for preventing cardiovascular diseases after ischemic stroke and thromboembolism related to atrial fibrillation, artificial heart valves, deep vein thrombosis, and pulmonary embolism. Warfarin is commonly used in combination with other drugs such as diuretics in order to treat the comorbidity. Although several warfarin-diuretics interactions have been reported, the results are conflicting. Therefore, the initial aim of this study was to identify the effects of diuretics on the warfarin response in patients with atrial fibrillation. Methods: One hundred forty six patients with atrial fibrillation who were on anticoagulation therapy with warfarin and maintained INR levels of 2-3 for three consecutive times were followed up, retrospectively. Stable warfarin doses and INR per stable warfarin dose were compared according to age, gender, comorbidity, and concurrent medication. The stable warfarin dose was defined as the maintenance dose of warfarin of the measured patient whose INR was within the target INR range more than 3 times consecutively. Results: The differences of stable warfarin doses in patients with ($3.22{\pm}1.21$ mg/day) and without ($3.58{\pm}1.14$ mg/day) diuretics were marginally significant (P=0.069). On the other hand, stable warfarin doses were $2.97{\pm}1.10$ mg/day in patients with thiazide (n=36) and $3.58{\pm}1.14$ mg/day in patients without diuretics (n=82), which was statistically significant (p=0.009). INR values per stable warfarin dose in patients with diuretics and thiazide were $0.84{\pm}0.31$ and $0.90{\pm}0.34$, respectively, which were statistically different from those without diuretics ($0.72{\pm}0.21$, P=0.010 and P=0.006, respectively). Age, gender, and concurrent use of thiazide diuretics were found to have significant influence on the warfarin response from multivariate analysis. Conclusion: Our study showed that the concurrent use of thiazide diuretics could increase the response of warfarin in patient with atrial fibrillation. Therefore, clinicians should be aware that warfarin dose needs to be adjusted when it is used with thiazide diuretics concomitantly.

Granulocytic Sarcoma: Results of Radiotherapy (Granulocytic Sarcoma : 방사선 치료 성적)

  • Song Mi Hee;Chung Eun Ji;Seong Jin Sil;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.10 no.2
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    • pp.261-266
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    • 1992
  • We analyzed retrospectively the patients of granulocytic sarcoma treated with radiotherapy at the Department of Radiation Oncology, Yonsei University College of Medicine from Mar 1987 to Mar.1992 in an attempt to review our experience with irradiation of granulocytic sarcoma and to evaluate the treatment results for the radiation dose response. Fourteen lesions of granulocytic sarcoma in 9 patients were developed in variable clinical settings such as AML, CML and without leukemia. The involved lesions were bone, lymph node, soft tissue and skin in descending order of occurrence. All of the lesions in 9 patients were treated with external beam radiotherapy (Co-60 or electron beam). Both age distribution and clinical settings did not show any correlation with the response to treatment. The response to treatment seemed to be better for lesions in the bone than in other involved lesions. The majority received local irradiation of a total dose of more than 2000 cGy. Radiation dose of more than 2000 cGy showed excellent local control of $100\%$, (11/11), while local control decreased to $33\%$(1/3) with total dose less than 2000 cGy. In conclusion, local radiotherapy seems to be very effective for palliative or curative aim of granulocytic sarcoma, and a radiation dose more than 2000 cGy is highly recommended.

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p53 Nuclear Accumulation as a Possible Biomarker for Biological Radio-dosimetry in Oral Mucosal Epithelial Cells

  • Kim, Youn-Young;Kim, Jong-il;Kim, Jin;Yook, Jong-In;Kim, The-Hwan;Son, Young-Sook
    • BMB Reports
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    • v.34 no.2
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    • pp.123-129
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    • 2001
  • Cellular response to ionizing radiation is affected by cell types, radiation doses, and post-irradiation time. Based on the trypan blue dye exclusion assay in normal oral mucosal cells (OM cells), a 48 h post-irradiation was sufffcient and an adequate time point for the evaluation of radiation sensitivity Its $LD_{50}$ was approximately 1.83 Gy To investigate possible biomarkers useful for the biological radiodosimetry of normal epithelial cells (p53, c-fos, cyclin D1, cdc-2, pRb) EGF receptor phosphorylation and Erk activation were evaluated at different radiation doses and different post-irradiation times. From 0.5 Gy, p53 was accumulated in the nucleus of basal cells of the OM raft culture at 4 h post-irradiation and sustained up to 24 h post-irradiation, which suggests that radiation-induced apoptosis or damage repair was not yet completed. The number of p53 positive cells and biosynthesis of p53 were correlated with radiation doses. Both cyclin D1 and c-fos were only transiently induced within 1 h post-irradiation. Cyclin D1 was induced at all radiation doses. However, cfos induction was highest at 0.1 Gy, approximately 7.3 fold more induction than the control, whose induction was reduced in a reverse correlation with radiation dose. The phosphorylation pattern of cdc-2 and pRb were unaffected by radiation. In contrast to A431 tails overexpressing the EGF receptor approximately 8.5 fold higher than normal epithelial, the OM cells reduced the basal level of the EGF receptor phosphorylation in a radiation dose dependent fashion. In conclusion, among radiation-induced biomolecules, the p53 nuclear accumulation may be considered for the future development of a useful marker far biological radiodosimetry in normal epithelial tissue since it was sustained for a longer period and showed a dose response relationship. Specific c-fos induction at a low dose may also be an important finding in this study It needs to be studied further for the elucidation of its possible connection with the low dose radio-adaptive response.

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