• Title/Summary/Keyword: dose response

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The Effects of Tramadol on Electroencephalographic Spectral Parameters and Analgesia in Rats

  • Jang, Hwan-Soo;Jang, Il-Sung;Lee, Maan-Gee
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.3
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    • pp.191-198
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    • 2010
  • The effects of different doses of tramadol on analgesia and electroencephalographic (EEG) spectralparameters were compared in rats. Saline or tramadol 5, 10, 20 or 40 mg/kg was administered. The degree of analgesia was evaluated by tail-flick latency, and the degree of seizure was measured using numerical seizure score (NSS). Additionally, band powers, median power frequency and spectral edge frequency 95 were measured to quantify the EEG response. All doses of tramadol produced spike-wave discharge. Tramadol significantly and dose-dependently increased the analgesia, but these effects did not correspond with the changes in the EEG spectral parameters. NSS significantly increased in the Tramadol 20 and 40 mg/kg treatment groups compared to the Control and TRA5 groups, and two rats given 40 mg/kg had convulsions. In conclusion, tramadol dose-dependently increased the analgesic effect, and the 10 mg/kg dose appears to be a reliable clinical dose for analgesia in rats, but dose-dependent increases in analgesia and seizure severity did not correlate with EEG spectral parameters.

THERMOLUMINESCENCE DOSIMETRIC PROPERTIES OF Ge- AND Er-DOPED OPTICAL FIBRES AND THEIR APPLICATION IN THE MEASUREMENT OF DEPTH -DOSE IN SOLID WATER PHANTHOM

  • Amin, Y.M.;Abdulla, Y.A.;Khoo, B.H.
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.143-147
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    • 2001
  • The dosimetric properties of Ge- and Er-doped optical fibres are studied. The Ge-doped fibre is found to be more sensitive to radiation and there is little fading of TL signal compared with Er-doped fibre. The Ge- and Er-doped fibres showed a linear response over a range of ${\sim}1\;Gy$ to about 120 Gy and ${\sim}1Gy$ to about 250Gy respectively. The Ge-doped fibre is found to be dose-rate independent both for photons and electron beams of energy ranging from 6 to 10 MeV and 6 to 12 MeV respectively. The fibre is energy independent for energy greater than ${\sim}0.1\;MeV$ for photon or 0.1 MeV for electron beam. From the depth-dose measurement, it was found that the position of maximum dose, dmax, increased with increasing energy ranging from ${\sim}2\;cm$ and ${\sim}2.5\;cm$ for 6 MeV and 10 MeV photons respectively. The central axis percentage depth dose at 10 cm depth was found to be in good agreement with the value obtained using ionization chamber.

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Four-Week Repeated-Dose Toxicity Studies of CONP01 in Rats (랫드에서 CONP01에 대한 4주 반복투여 독성연구)

  • Hong Dong Ho;Zhang Hu-Song;Kim Kwang-Ho;Gil Gi Hyun;Kim Jae Min;Han Myong Kyu;Bae Jin-Sook;Kim Nam Du;Lee Hyun Kul;Lee Jung Suk;Lee Sun Kyung;Park Chan Koo;Song Si Whan
    • Toxicological Research
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    • v.20 no.4
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    • pp.349-357
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    • 2004
  • This study was performed to evaluate repeated-dose toxicities of CONP01 in Sprague-Dawley rats. CONP01, a new antiarthritic agent was administered orally to rats at dose levels of 0, 125, 500 and 2,000 mg/kg/day for 4 weeks. In present study, there were no dose response changes in mortality, clinical signs, body weight changes, food and water consumption, ophthalmoscopy, organ weights, urine analysis, hematological findings, and biochemical examination of all animals treated with CONP01. Gross and histopathological findings revealed no evidence of specific toxicity related to CONP01. These result suggest that no observed adverse effect level (NOAEL) of CONP01 may be over 2,000 mg/kg in rats.

Radiation Effect on Mouse Jejunal Crypt Cells by Single and Split Irradiation (단일조사와 분할조사시 마우스 공장 소낭선세포의 방사선효과에 관한 실험적 연구)

  • Koh Byung Hee;Hahm Chang Kok;Kim Jung Jin;Park Chan Il
    • Radiation Oncology Journal
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    • v.3 no.1
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    • pp.1-8
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    • 1985
  • To determine the dose·survival and repair characteristics of the jejunal crypt cells, experimental study was carried out using total 70 mice. Single or split irradiations of 1,100 to 2,200 rad were delivered to whole bodies of $C_{57}$ BL mice, using a cesium 137 animal irradiator and those mice were sacrificed after 90 hours. The number of regenerating crypts per jejunal circumference was counted by a jejunal crypt cell assay technique and dose·response curve was measured. The results were as follows : 1. The average number of jejunal crypts per circumference in control group was 140. In a single irradiation group, the number of regenerated jejunal crypts was, 125, 56, 2 in each subgroup of 1,100 rad, 1,400 rad and 1,800 rad respectively. In split irraiation group, it was 105,44,2 in each subgroup of 1,400rad 1,800rad and 2,200rad respectively. 2. Mean lethal dose of mouse jejunal crypt cell was 167 and 169 rad respectively in a single and split irradiation. 3. Repair dose of sublethal damage was 280 rad. 4. Sublethal damage was completely repaired within 4 hours between the split dose of irradiation.

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Efficacy of Half Dose House Dust Mites-Specific Immunotherapy on Canine Atopic Dermatitis

  • Park, Jeong-Ho;Lee, Wang-Hui;Park, Seong-Jun
    • Journal of Veterinary Clinics
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    • v.34 no.1
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    • pp.18-22
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    • 2017
  • The aim of this study was to prove that the hypothesis of half dose (HD) allergen-specific immunotherapy (ASIT) in the treatment of canine atopic dermatitis (CAD) would result in a similar success rate compared to the standard dose (SD) ASIT. Clinical signs were evaluated using a third version of the Canine Atopic Dermatitis Extent and Severity Index (CADESI-03) prior to ASIT (day 0), at the end of induction (day 43), and at three month afterwards (day 90). Of the 18 atopic dogs, 12 dogs (SD group: 6; HD group: 6) had a good - excellent response to the house dust mites-specific immunotherapy. The efficacies of ASIT were 66.6% in both groups. The grades of reduction rate CADESI-03 were not different between two groups. Therefore, half dose protocol of house dust mites-specific immunotherapy is an effective and efficient method to treat CAD.

Antioxidant Effect of Annexin A-1 Induced by Low-dose Ionizing Radiation in Adipose-derived Stem Cells

  • You, Ji-Eun;Lee, Seung-Wan;Kim, Keun-Sik;Kim, Pyung-Hwan
    • Biomedical Science Letters
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    • v.26 no.4
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    • pp.249-255
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    • 2020
  • Radiation therapy is one of the primary options for the treatment of malignant tumors. Even though it is an effective anti-cancer treatment, it can cause serious complications owing to radiation-induced damage to the normal tissue around the tumor. It was recently reported that normal stem cell response to the genotoxic stress of ionizing radiation can boost the therapeutic effectiveness of radiation by repairing damaged cells. Therefore, we focused on annexin A-1 (ANXA1), one of the genes induced by low-dose irradiation, and assessed whether it can protect adipose-derived stem cells (ADSCs) against oxidative stress-induced damage caused by low-dose irradiation and improve effectively cell survival. After confirming ANXA1 expression in ADSCs transfected with an ANXA1 expression vector, exposure to hydrogen peroxide (H2O2) was used to mimic cellular damage induced by a chronic oxidative environment to assess cell survival under oxidative conditions. ANXA1-transfected ADSCs demonstrated that increased viability compared with un-transfected cells and exhibited enhanced anti-oxidative properties. Taken together, these results suggest that ANXA1 could be used as a potential therapeutic target to improve the survival of stem cells after low-dose radiation treatment.

Novel polyvinyl alcohol film dosimeter containing 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide dye for high dose application

  • Khalid A. Rabaeh;Ahmed A. Basfar;Issra' M.E. Hammoudeh
    • Nuclear Engineering and Technology
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    • v.55 no.9
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    • pp.3383-3387
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    • 2023
  • A new dyed polyvinyl alcohol (PVA) film dosimeter based on 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MMT) tetrazolium dye is proposed in this study for measuring high gamma radiation dose. Gamma cell irradiator that contains Co-60 gamma-ray source was used to expose the novel MMT-PVA films to different doses up to 25 kGy. The changed in optical property of irradiated and unirradiated films were characterized by UV-Vis spectrophotometer. The results show that the dose sensitive and the linear range of irradiated films were increased considerably with increase of MMT concentration from 1 to 5 mM. The dose response of dyed PVA film changed substantially with changing relative humidity (12-74%) as well as irradiation temperature (10-40 ℃). The absorbance of the unirradiated films does not change up to 10 days in dark while a significant increase in their absorbance was reported for similar films under fluorescent light. The irradiated dosimeters that kept in dark showed a perfect stability for 54 days. It was found that no obvious impact of dose rate on the irradiated MMT-PVA film dosimeters.

Calibration of Optically Stimulated Luminescent nanoDot Dosimeter for 6 MV Photon Beam (6 MV 광자 빔에 대한 광자극형광나노닷선량계의 교정)

  • Kim, Jongeon;Kim, Seonghu;Lee, Hyoyeong
    • Journal of the Korean Society of Radiology
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    • v.7 no.1
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    • pp.93-98
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    • 2013
  • The purpose of this study is to investigate the calibration of an optically stimulated luminescent nanoDot dosimeter(OSLnD) to 6 MV photon beam. Dose ranges of the calibration of linear and non-linear from the analysis of dose response of the OSLnD were decided. To evaluate the accuracy of calibration equation and the calibration, the sets of the calibration and quality control dosimeter were used to make. The calibrations were performed by the linear and the non-linear in the dose range of 0~300 cGy and 20~1300 cGy, respectively. The errors of the calibration were acquired less than 0.1% respectively from the measurement of the quality control dosimeters for the calibration of linear and the non-linear. This study provides the calibration equation of the OSLnD to the 6 MV photon beam.

Comparison of Parameter Using the Repair Survival Model Irradiated High-LET (LET 증가에 따른 회복 생존 모델의 파라미터 값 비교)

  • Choi, Eunae
    • Journal of the Korean Society of Radiology
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    • v.11 no.4
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    • pp.177-181
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    • 2017
  • Dose response curves using absorbed dose to the biological effect are usually available in case of conventional X beam. However, absorbed dose is not consider in treatment planning for carbon beam such as heavy ions. Because the biological effects also depend on other quantities such as the local variation, which is often characterized by the linear energy transfer (LET). So LQ model cannot explain the entire response of fractionated carbon beam irradiation. The variation in LET with penetration depth leads to substantial differences in biological effect of carbon beam. And it is therefore essential in treatment planning to calculate not only the absorbed dose but also the LET to estimate the biological outcome of the radiation of interest. LET variation plays an important role in the fractionated irradiations. It is suggested that consideration of LET is necessary in biophysical model.

Impact of Inadequate Doses of Rituximab in the Treatment of Diffuse Large B Cell Lymphoma in Malaysian Patients

  • Gan, Gin Gin;Subramaniam, Rajaletchumy;Bee, Ping Chong;Chin, Edmund Fui Min;Abdul-Halim, Habibah;Tai, Mei Chee
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.4
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    • pp.1703-1706
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    • 2014
  • Background: The current standard treatment for patients with newly diagnosed diffuse large B cell lymphoma (DLBCL) is rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP). A significant number of patients were not treated with recommended dose of rituximab due to limited financial resources in Malaysia. This study evaluates the efficacy of R-CHOP like chemotherapy in Malaysian patients with DLBCL. Materials and Methods: The study comprised a retrospective analysis of patients with DLBCL treated at a single centre. The outcome was compared with patients who were treated with R-CHOP like and CHOP like chemotherapy. Patients who were treated with lower dose of rituximab was subanalysed for outcome. Results: A total of 86 patients who had CHOP-like chemotherapy were included. Only 39 (45%) patients had rituximab and only 12 (29%) patients had the recommended dose. The overall response (OR) and complete response (CR) rates were 88% and 81% respectively. There was no significant difference in OR and CR in patients who had rituximab and those without rituxmab. Those with International Prognostic Index (IPI) score of ${\leq}2$ had significant higher CR rate, progression free survival (PFS) and overall survival (p<0.001). Conclusions: The lack of significant improvement in CR and DFS in our patients may be due to an inadequate dose of rituximab.