• Title/Summary/Keyword: Low Dose

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Dose Intensity of Oxaliplatin in 5-Fluorouracil and Leucovorin Regimens in Pretreated Metastatic Colorectal Cancer (5-Fluorouracil, Leucovorin과 병용 투여된 Oxaliplatin의 Dose Intensity가 재발된 전이성 대장암 치료에 미치는 영향)

  • Jeong, Kyong-Ju;Choi, Seung-Ki;Oh, Jung-Mi
    • Korean Journal of Clinical Pharmacy
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    • v.14 no.1
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    • pp.1-10
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    • 2004
  • Studies of oxaliplatin, 5-fluorouracil and leucovorin in pretreated metastatic colorectal cancer showed that oxaliplatin dose intensity is important prognostic factor for objective response rates and progression-free-survival (PFS). To evaluate response rates, PFS and toxicity according to oxaliplatin dose intensity, we retrospectively analyzed data from patients with metastatic colorectal cancer received oxaliplatin,5-fluorouracil, leucovorin regimens. Sixty-three patients were reviewed in this study, 42 patients received low dose intensity oxaliplatin (LDI: $\leq85\;mg/m^2/2wks$) and 21 patients high dose intensity oxaliplatin (HDI: $>85\;mg/m^2/2wks$). Objective responses occurred in 10 $(47.7\%)$ HDI patients and 9 $(21.4\%)$ LDI patients (p = 0.014). Median PFS was 24.7 weeks in HDI group, with $45.1\%$ of HDI patients progression free at 6 months, and 20.5 weeks in LDI group, with $33.5\%$ of LDI patients progression free at 6 months (p = 0.344). Increased oxaliplatin dose intensity was not associated with neutropenia, thrombocytopenia, neuropathy, nausea and vomiting. This study showed that oxaliplatin dose intensification significantly improves objective response rate in pretreated metastatic colorectal cancer without increasing severe toxicity.

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THE FACTORS WHICH AFFECT THE EXTERNAL RADIATION DOSE RATE OF PET-CT PATIENTS

  • Cho, Ihn Ho;Kim, Su Jin;Han, Eun Ok
    • Journal of Radiation Protection and Research
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    • v.37 no.4
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    • pp.231-236
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    • 2012
  • This study derived measures to reduce exposure doses by identifying factors which affect the external radiation dose rate of patients treated with radiopharmaceuticals for PET-CT tests. The external radiation dose rates were measured on three parts of head, thorax and abdomen at a distance of 50cm from the surface of 60 PET-CT patients. It showed there are changes in factors affecting the external radiation dose rate over time after the administration of F-18 FDG. The external radiation dose rate was lower in the patients with more water intake than those with less water intake before the injection of radiopharmaceuticals at all three points: right after the injection of radiopharmaceuticals (average 4.17 mins), after the pre-PEET-CT urination step (average 77.47 mins), and right after the PET-CT test (average 114.15 mins). The study also found there is a need to increase the amount of water intake before the injection of radiopharmaceuticals in order to maintain a low external radiation dose rate in patients. This strategy is only possible under the assumption that the quality of the video has not changed after conducting this study on the relations between the image and quality. This study also found a need to use radiopharmaceuticals with the minimum amount needed for each patient because F-FDG doses affects the external radiation dose rate at the point right after the injection of radiopharmaceuticals. Urination frequency was the most significant factor to affect the external radiation dose rates at the point right after the PET-CT test and the point after the pre-PET-CT urination step. There is a need to realize the strategy to increase the urination frequency of patients to maintain the external radiation dose rate low (average 77.47 mins) before and after the injection of radiopharmaceuticals. In addition, at this point, there is a need to take advantage of personal strategies because the external radiation dose rate is lower if the fasting time is shorter, the contrast medium is used, and the amount of water intake is increased after the administration of radiopharmaceuticals. Finally this study found the need to be able to generalize these findings through an in-depth research on the factors affecting the external radiation dose rate, which includes radiopharmaceutical dose, urination frequency, the amount of water intake, fasting time and the use of contrast medium.

Genotoxicity of low-dose Glyphosate by Sister Chromatid Exchange (자매염색분체교환을 통한 글라이포세이트 유전독성)

  • Lee, Sang Hoon;Kim, Sung Jin;Choi, Woo Ik;Jin, Sang Chan;Choi, In Jang;Lee, Jae Ho
    • Journal of The Korean Society of Clinical Toxicology
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    • v.12 no.1
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    • pp.8-13
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    • 2014
  • Purpose: Glyphosate (N-phosphonomethyl glycine) is widely used as an herbicide for weed control in rural areas. It is also readily available for suicide attempts. Glyphosate has high toxicity and negatively affects the human body. The aim of this investigation was to study the genotoxicity of a low-concentration of glyphosate through sister chromatid exchange (SCE) in human blood lymphocytes in vitro. Methods: Primary lymphocyte cultures were obtained from blood samples of 11 males and seven females who had been exposed to glyphosate (0, 100, 200, and 300 ng/mL). The frequency of SCEs was examined and statistical analysis was performed. Results: All doses of glyphosate induced a significant dose-dependent increase in SCE frequency compared with the control group (P<0.001). In particular, the SCE frequency for exposure to low-dose glyphosate was significantly higher in females than in males. Conclusion: According to the result of this study, even a low-dose of glyphosate may damage DNA and females are more vulnerable to glyphosate.

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Hormesis as a Confounding Factor in Epidemiological Studies of Radiation Carcinogenesis

  • Sanders Charles L.
    • Journal of Radiation Protection and Research
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    • v.31 no.2
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    • pp.69-89
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    • 2006
  • Biological mechanisms for ionizing radiation effects are different at low doses than at high doses. Radiation hormesis involves low-dose-induced protection and high-dose-induced harm. The protective component is associated with a reduction in the incidence of cancer below the spontaneous frequency, brought about by activation of defensive and repair processes. The Linear No-Threshold (LNT) hypothesis advocated by the International Commission on Radiological Protection (ICRP) and the Biological Effects of ionizing Radiation (BEIR) Report VII for cancer risk estimations Ignores hormesis and the presence of a threshold. Cancer incidences significantly less than expected have been found in a large number of epidemiological studies including, airline flight personnel, inhabitants of high radiation backgrounds, shipyard workers, nuclear site workers in scores of locations throughout the world, nuclear power utility workers, plutonium workers, military nuclear test site Participants, Japanese A-bomb survivors, residents contaminated by major nuclear accidents, residents of Taiwan living in $^{60}Co$ contaminated buildings, fluoroscopy and mammography patients, radium dial painters, and those exposed to indoor radon. Significantly increased cancer was not found at doses <200 $mSv^*$. Evidence for radiation hormesis was seen in both sexes for acute or chronic exposures, low or high LET radiations, external whole- or partial body exposures, and for internal radionuclides. The ubiquitous nature of the Healthy Worker Effect (HWE)-like responses in cellular, animal and epidemiological studies negates the HWE as an explanation for radiation hormesis. The LNT hypothesis is wrong and does not represent the true nature of the dose-response relationship, since low doses or dose-rates commonly result in thresholds and reduce cancer incidences below the spontaneous rate. Radiation protection organizations should seriously consider the cost and health implications of radiation hormesis.

Effect on Pancreatic Beta Cells and Nerve Cells by Low LET X-ray (Low LET X-ray가 췌장 ${\beta}$ 세포와 신경세포에 미치는 효과)

  • Park, Kwang-Hun;Kim, Kgu-Hwan
    • Journal of radiological science and technology
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    • v.37 no.1
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    • pp.21-28
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    • 2014
  • Cultured pancreatic beta cells and nerve cells, it is given normal condition of 10% FBS (fetal bovine serum), 11.1 mM glucose and hyperglycemia codition of 1% FBS, 30 mM glucose. For low LET X-ray irradiated with 0.5 Gy/hr dose-rate(total dose: 0.5 to 5 Gy). Survival rates were measured by MTT assay. When non irradiated, differentiated in the pancreatic beta cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a small reduction. However increasing the total dose of X-ray, the survival rate of normal conditions decreased slightly compared to the survival rate of hyperglycemia conditions, the synergistic effect was drastically reduced. When non irradiated, undifferentiated in the nerve cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a large reduction. As the cumulative dose of X-ray normal conditions and hyperglycemia were all relatively rapid cell death. But the rate of decreased survivals by almost parallel to the reduction proceed and it didn't show synergistic effect.

INVOLVEMENT OF p27CIP/KIP IN HSP25 OR INDUCIBLE HSP70 MEDIATED ADAPTIVE RESPONSE BY LOW DOSE RADIATION

  • Seo, Hang-Rhan;Chung, Hee-Yong;Lee, Yoon-Jin;Baek, Min;Bae, Sang-Woo;Lee, Su-Jae;Lee, Yun-Sil
    • Nuclear Engineering and Technology
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    • v.38 no.3
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    • pp.285-292
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    • 2006
  • Thermoresistant (TR) clones of radiation-induced fibrosarcoma (RIF) cells have been reported to show an adaptive response to 1cGy of low dose radiation, and HSP25 and inducible HSP70 are involved in this process. In this study, to further elucidate the mechanism by which HSP25 and inducible HSP70 regulate the adaptive response, HSP25 or inducible HSP70 overexpressed RIF cells were irradiated with 1cGy and the cell cycle was analyzed. HSP25 or inducible HSP70 overexpressed cells together with TR cells showed increased G1 phase after 1cGy irradiation, while RIF cells did not. $[^3H]-Thymidine$ and BrdU incorporation also indicated that both HSP25 and inducible HSP70 are involved in G1 arrest after 1cGy irradiation. Molecular analysis revealed upregulation of p27Cip/Kip protein in HSP25 and inducible HSP70 overexpressed cells, and cotransfection of p27Cip/Kip antisense abolished the induction of the adaptive response and 1cGy-mediated G1 arrest. The above results indicate that induction of an adaptive response by HSP25 and inducible HSP70 is mediated by upregulation of p27Cip/Kip protein, resulting in low dose radiation-induced G1 arrest.

Low Dose Yeast Hydrolysate in Treatment of Obesity and Weight Loss

  • Jung, Eun Young;Lee, Jong Woo;Hong, Yang Hee;Chang, Un Jae;Suh, Hyung Joo
    • Preventive Nutrition and Food Science
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    • v.22 no.1
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    • pp.45-49
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    • 2017
  • The anti-obesity effects of yeast hydrolysate (YH) supplementation (1.0 g/d) have already been demonstrated. We investigated whether a low dose of YH (0.5 g/d, YH-500) also has the anti-obesity effects. Thirty obese women were randomly assigned to the control or YH-500 groups. After 8 weeks, weight and body mass index were significantly reduced by the YH treatment (0.5 g/d) (P<0.05). The YH-500 group lost a significant amount of body fat after the 8-week treatment: fat mass 25.9 kg (baseline) versus 23.8 kg (8th week), P<0.01; fat mass ratio 38.8% (baseline) versus 36.5% (8th week), P<0.05. The YH-500 group showed a significant reduction in calorie intake during the 8-week treatment (P<0.001). The control group wanted to eat much more food (P<0.05) and sometimes thought about eating more often compared with the YH-500 group (P<0.05). Whereas the control group showed a slightly increased sweet preference, the YH-500 group showed a significant reduction in sweet preference (P<0.05). In conclusion, low dose YH supplementation (0.5 g/d) may induce a reductions in weight and body fat in obese women via the reduction of calorie intake.

Efficacy and Safety of Low Dose Ketamine and Midazolam Combination for Diagnostic Upper Gastrointestinal Endoscopy in Children

  • Akbulut, Ulas Emre;Cakir, Murat
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.18 no.3
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    • pp.160-167
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    • 2015
  • Purpose: We aimed to analyze the effectiveness and safety of low-dose midazolam and ketamine combination for upper gastrointestinal endoscopy (UGIE) in children. Methods: The study included the children (n=425, $10.78{\pm}3.81years$) who underwent UGIE for diagnostic purpose during 1 year period. All children were sedated with low dose midazolam (0.1 mg/kg) and ketamine (0.5 mg/kg) intravenously. Effectiveness of the sedation and complications during the procedure and recovery period were recorded. Results: Endoscopic procedure was successfully completed in 414 patients (97.4%; 95% confidence interval, 95.8-98.9). $Mean{\pm}standard$ deviation (SD) duration of procedure was $6.36{\pm}1.64minutes$ (median, 6.0 minutes; range, 4-12 minutes). Minor complications occurred during the procedure in 39.2% of the patients. The most common complication was increased oral secretion (33.1%). No major complications were observed in any patient. Age and Ramsay sedation scores of patients with complications during the procedure were lower than the others ($9.49{\pm}4.05years$ vs. $11.61{\pm}3.43years$, p=0.002 and $2.10{\pm}1.46$ vs. $4.37{\pm}1.16$, p=0.001). Mean recovery time was 22 minutes (range, 10-90 minutes; $mean{\pm}SD$, $25{\pm}12.32minutes$). Minor complications developed during recovery in 60.1% of the patients. The most common complication was transient double vision (n=127, 30.7%). Emergence reaction was observed in 5 patients (1.2%). Conclusion: The procedure was completed with high level of success without any major complication in our study. Combination of low-dose midazolam and ketamine is a suitable sedation protocol for pediatric endoscopists in UGIE.

The effects of low dose doxycycline regimen on gingival crevicular fluid enzyme actmty of diabetic patients with periodontitis and adult periodontitis patients (저용량 독시싸이클린 투여가 당뇨환자 마치 성인성 치주염 환자의 치은열구액내 효소 활성도에 미치는 영향에 관한 비교연구)

  • Jeong, Seong-Nyum;Han, Soo-Boo
    • Journal of Periodontal and Implant Science
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    • v.27 no.4
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    • pp.701-722
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    • 1997
  • It was reported that low dose doxycycline(LDD) regimen could inhibit pathologically elevated collagenase activity in the gingival crevicular fluid of petients with adult periodontitis without producing typical antibiotic side effects. The purpose of this study was to evaluate the effects of LDD regimen(20mg) administered during non-surgical therapy on clinical index and gingival crevicular fluid enzyme activity in diabetics who are at high risk for periodontal disease. Forty-nine subjects having at least two sites with probing pocket depths greater than 4mm were selected. In this double-blind, placebo-controlled study, the patients were administered 20 mg doxycycline capsule or placebo capsule b.i.d. for 2 weeks. Clinical parameters of dental plaque, gingival inflammation, probing pocket depth and probing attachment level were assessed at week 0, 2, 4, and 8. Gingival crevicular fluid samples were collected at the same time to evaluate the activities of collagenase and elastase. Clinical parameters and elastase activity were significantly reduced in all groups compared to the baseline value after treatment. Significantly greater reduction in pocket depth and gain in attachment level was shown in the LDD-administered group compared to placebo group in both adult periodontitis and diabetic patients. Total collagenase activity was also reduced significantly in all groups after treatment, but the greater reduction was seen in the LDD-administered diabetics group compared to relevant placebo group(at 4, 8week). Significantly greater reduction in active collagenase activity was also seen in the LDD-administered group compared to placebo group in diabetic patients(at 2, 4, 8week). These results indicated that use of low dose doxycycline could be aueseful adjunct to instrumentation therapy in the management of diabetic patient with periodontitis as well as adult periodontitis patient.

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Effect of Low-Dose Radiation on Quality Characteristics of Takju (저선량 방사선 처리가 탁주 품질특성에 미치는 영향)

  • Lee, Yun-Gyu;Tak, Eun-Mi;Kim, Bo-Mi-Na;Seo, Choung-Won;Choi, Seung-Hwan;Shin, Yong-Seob;Kim, Seon-Chil
    • Korean Journal of Digital Imaging in Medicine
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    • v.13 no.3
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    • pp.133-137
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    • 2011
  • This research investigated how low dose radiation affected the quality characteristics of Takju. The treatment group were the quality characteristics of control group, Takju treated by radiation of separate 4, 7, 10 Gy and sterilized Takju. We measured pH, titratable acidity, alcohol, brix, total viable cell count, Hunter's color values, sensory characteristic. As a result, We discovered there were minute changes in pH, titratable acidity, alcohol, brix, total viable cell count. Likewise, The color appeared changes on separate radiation dose. In the sensory characteristic, People's preference ranked better than average level according to priority Takju treated by 4, 7, 10 radiation. In conclusion, Low dose radiation had little effect on the quality characteristics of Takju. However, Takju received a favorable review by some people In test of taste such as after taste. So We thought, such as preservation, the research using the radiation should be continually conducted.

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