• Radiation Oncology Journal
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• 제7권2호
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• pp.171-183
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• 1989

Roesch의 생존 방정식속에 세포증식으로 일어나는 생존증가를 가장 일반적 형식으로 포함시킨 식을 유도하고 이 식으로부터 저선량률 방사선에만 적용되는 동결과선량식 (Isoeffect formula)을 유도하였다. 이 저선량률식이 파라메터 하나로 결정해주는 총선량은 Paterson과 Green에 의하여 얻어진 실험 임상결과와 일치한다. 이 파라메터와 선량률 효과 사이의 관계의 의의를 논하였다. 또한 고선량률 분절(fractionation) 치료와 동저선량률 계속치료를 연락하는 동결과 선량식을 유도 사용하여, Ellis가 잰 실험결과와 비교하였다. 그 결과, Ellis와 Paterson이 쓴 'tolerance'의 표준이 $\alpha/\beta$의 비 4Gy에 해당하는 것임이 밝혀졌다. 그러므로 이들의 'tolerance'의 표준은 'early effect'에만 두고 본 것이 아님을 알 수 있다. 개념적인 면에서도, 아래와 같은 새로운 견해가 나올 수 있다. KHT sarcoma의 생존선도 (survival curve)에 선량률 효과가 보이지 않는 이유로 $\alpha/\beta$의 비가 큰 점을 들을 수 있다. 이것은 이 survival curve에 어께 (shoulder)가 보이지 않는 것으로도 증명이 된다. Pierquin이 선량률에 무관하게 head and neck tumor치료에 같은 총선량을 쓴 것을 정당화시킬 수 있다.

• Journal of Yeungnam Medical Science
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• 제6권2호
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• pp.103-111
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• 1989

방사선 조사후 방광의 손상에 관한 실험에서 다음과 같은 결과를 얻었다. 1. 손상군, 회복군 모두에서 암수가 비슷한 변화를 보여 방사선에 의한 손상에서 암수의 차이는 없었다. 2. 점막의 변화는 40GY 조사군에서 50GY군 보다 빨리 회복됨이 관찰되었고 14주에서 대부분 소실되었다. 3. 혈관의 변화는 40GY, 50GY 모두에서 혈관확장증, 초자질화, 내피하층과 중간층의 섬유화 등이 관찰되었으며 혈관주변의 섬유화는 15주까지 관찰되었다. 결체조직과 균육층의 변화는 40GY, 50GY 모두에서 조사후 15주까지 지속됨을 볼 수 있었다. 마우스의 평균수명(460일-1000일)에 비해 본 연구의 추적 기간이 105일로서 충분히 길다고는 할 수 없으나 상기 여러 결과로 미루어 후기 반응의 감소 및 예방을 위해 세심한 조사 계획이 있어야 함을 시사하였다.

• 한국의학물리학회지:의학물리
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• 제29권2호
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• pp.73-80
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• 2018

Accelerated partial breast irradiation (APBI) is a new treatment delivery technique that decreases overall treatment time by using higher fractional doses than conventional fractionation. Here, a quantitative analysis study of CyberKnife-based APBI was performed on 10 patients with left-sided breast cancer who had already finished conventional treatment at the Inha University Hospital. Dosimetric parameters for four kinds of treatment plans (3D-CRT, IMRT, VMAT, and CyberKnife) were analyzed and compared with constraints in the NSABP B39/RTOG 0413 protocol and a published CyberKnife-based APBI study. For the 10 patients recruited in this study, all the dosimetric parameters, including target coverage and doses to normal structures, met the NSABP B39/RTOG 0413 protocol. Compared with other treatment plans, a more conformal dose to the target and better dose sparing of critical structures were observed in CyberKnife plans. Accelerated partial breast irradiation via CyberKnife is a suitable treatment delivery technique for partial breast irradiation and offers improvements over external beam APBI techniques.

• Radiation Oncology Journal
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• 제37권1호
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• pp.1-12
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• 2019

Despite recent innovation in treatment techniques and subsequently improved outcomes, the majority of glioblastoma (GBL) have relapses, especially in locoregional areas. Local re-irradiation (re-RT) has been established as a feasible option for recurrent GBL of all ages with safety, tolerability, and effectiveness both in survival and quality of life regardless of fractionation schedule. To keep adverse effects under acceptable range, cumulative dose limit in equivalent dose at 2 Gy fractions by the linear-quadratic model at α/β = 2 for normal brain tissue (EQD2) with narrow margin should be observed and single/hypofractionated re-RT should be undertaken very carefully to recurrent tumor with large volume or adjacent to the brainstem. Promising outcome of re-operation (re-Op) plus re-RT (re-Op/RT) need to be validated and result from re-RT with temozolomide/bevacizumab (TMZ/BV) or new strategy is expected. Development of new-concept prognostic scoring or risk group is required to select patients properly and make use of predictive biomarkers such as O(6)-methylguanine-DNA methyltransferase (MGMT) promotor methylation that influence outcomes of re-RT, re-Op/RT, or re-RT with TMZ/BV.

• Journal of Medicine and Life Science
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• 제20권2호
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• pp.89-93
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• 2023

We present three cases of patients with breast cancer and psoriasis who received radiotherapy following breast-conserving surgery. One patient developed an extensive flare-up of psoriasis during chemotherapy. After discontinuing chemotherapy, she received conventional radiotherapy to the ipsilateral whole breast, axillary, and supraclavicular lymph nodes with 50.4 Gy in 28 fractions and boosted with 10 Gy in five fractions to the tumor bed. Two patients received hypofractionated whole-breast radiotherapy at a total dose of 40.05-42.4 Gy in 15-16 fractions. In all three cases, there was no flare-up of psoriatic events at least 6 months after the completion of radiotherapy. We hypothesized that there is a close relationship between psoriatic events and the extent of trauma rather than the daily dose of the fraction. Therefore, we confirmed that the effect of radiotherapy on psoriatic events is minimal if the radiation field size does not exceed that of the whole breast.

• 공업화학
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• 제34권6호
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• pp.626-632
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• 2023

Acemannan, a highly acetylated glucomannan, was extracted from fresh Aloe vera leaves by ethanol fractionation, resulting in a concentration increase of more than threefold. The presence of acemannan was confirmed using FTIR and ¹H NMR analysis, revealing an average molecular weight of 780 kDa. The flocculating activity of the fractionated aloe gel polysaccharide was assessed through settling tests in a 1% (w/v) bentonite suspension. The results demonstrated that the aloe polysaccharide exhibited remarkable stability within a temperature range of 20~70 ℃. The maximal flocculation rate at different pH levels ranged from 93% to 97%, with an optimal dose for maximum flocculation rate between 0.25 mg/mL. Notably, the minimum dose required for flocculation was achieved at a pH of 3, attributed to the compression of electrostatic repulsion on the surface of bentonite particles. However, the flocs obtained under acidic conditions were less dense and compact, exhibiting lower sedimentation velocity compared to those formed under neutral and alkaline pH conditions. Additionally, the addition of salt showed a slight synergistic effect on flocculation, significantly enhancing the sedimentation velocity. This investigation highlights the potential of Aloe vera polysaccharide as a natural and edible flocculant, offering promising applications in various industries.

• Archives of Pharmacal Research
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• 제11권3호
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• pp.240-243
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• 1988

The hexane extract from Nutmeg, the seed of Myristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by $SiO_2$ column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B (II) and dehydrodiisoeugenol (III) were isolated as active principles. Compounds II and III, with a single treatment (200mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they possess CNS-depressant properties.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.718-722
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• 1998

Scopoletin (7-hydroxy-6-methoxycoumarin), a coumarin, was isolated from the aerial part of Solanum lyratum Thunb. by the activity-guided fractionation employing carbon te trachloride-intoxicated primary cultured rat hepatocytes as a screening system. Its hepatoprotective activity was first evaluated by measuring the release of glutamic pyruvic transaminase and sorbitol dehydrogenase from carbon tetrachloride-intoxicated rat hepatocytes into the culture medium. Scopoletin significantly reduced the releases of glutamic pyruvic transaminase and sorbitol dehydrogenase from the carbon tetrachloride-intoxicated primary cultured rat hepatocytes by 53% and 58%, respectively, from the toxicity in a dose-dependent manner over concentration ranges of 1mcM to 50mcM. Further studies revealed that at the concentration of 10mcM, scopoletin significantly preserved glutathione content by 50% and the activity of superoxide dismutase by 36% and also inhibited the production of malondialdehyde to the degree as seen in the control.

• Biomolecules & Therapeutics
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• 제17권4호
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• pp.412-417
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• 2009

In the course of screening for antioxidant compounds by measuring the radical scavenging effect on DPPH (1,1-diphenyl- 2-picrylhydrazyl), a total extract of the twigs of Vitex rotundifolia (Verbenaceae) was found to show potent antioxidant activity. Subsequent activity-guided fractionation of the methanolic extract led to the isolation of three iridoid compounds, 10-O-vanilloylaucubin (1), 10-O-p-hydroxybenzoylaucubin (2) and aucubin (3), two C-glycoside flavones, vitexin (4) and orientin (5), and a quinic acid derivative, 3,4-di-O-caffeoylquinic acid (6). Their structures were elucidated by spectroscopic studies. Among them, compounds 5 and 6 showed the significant antioxidative effects on DPPH free radical scavenging test. In riboflavin-NBT-light and xanthine-NBT-xanthine oxidase systems, compounds 5 and 6 exhibited the formation of the blue formazan in a dose-dependent manner. Compounds 5 and 6 showed better superoxide quenching activities than vitamin C.

• 생약학회지
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• 제29권4호
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• pp.384-390
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• 1998

The methanol extract of Torilis Fructus showed potent anti-edematous effect in carrageenan-induced paw edema in rats. Systematic fractionation of the extract with hexane, chloroform, ethyl acetate and butanol resulted in potent anti-edematous action only in hexane fraction at an oral dose of 237 mg/kg which is corresponding to 4.8 g of raw Fructus. This hexane fraction showed inhibitory effects at 77 mg/kg p.o on vascular permeability in mice, at 8mg/pouch on leucocyte emigration in rats, and at 120 mg/kg p.o. on adjuvant arthritis model in rats. These results demonstrate that hexane fraction of the extract possesses potent anti-inflammatory effect which may support its traditional uses.