• Title/Summary/Keyword: radiation dose

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Correlation Between Response to Induction Chemotherapy and Subsequent Radiotherapy in Previously Untreated Patients with Squamous Cell Carcinomas of the Head and Neck (두경부의 악성종양(편평상피암) 환자에서 유도화학요법에 의한 종양의 관해와 방사선치료에 의한 관해의 상호 관계)

  • Park Woo Yoon;Yoo Seong Yul;Koh Kyoung Hwan;Cho Chul Koo;Park Young Hwan;Shim Youn Sang;Oh Kyung Kyoon;Lee Yong Sik
    • Radiation Oncology Journal
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    • v.8 no.2
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    • pp.207-212
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    • 1990
  • To determine the correlation between the response to induction chemotherapy and subsequent radiotherapy we analyzed the clinical records of 60 patients with locally advanced carcinoma of the head and neck retrospectively who had completed a full course ($2\~3$ cycle) of induction chemotherapy and curative radiotherapy in Korea Cancer Center Hospital between 1986 and 1989. Chemotherapy was administeredd with CDDP+Bleomycin (BP) in 20, CDDP+5-FU (FP) in 37, and hybrid of BP and FP in three patients. Radiotherapy was giver conventionally with a dose of 65 to 75 Gy or more over seven to eight weeks according to the size of lesion. Response rates following induction chemotherapy were $80\%$ for the tumors and $879\%$ for the nodes whereas complete reponse rates were $12\%\;and\;13\%$, respectively. Six months after radiotherapy $67\%$ of the tumors and $77\%$ of the nodes achieved a complete response. Among the 48 tumor responders and the 31 nodal responders to chemotherapy,39 ($81\%$) and 28 ($90\%$), respectively, achieved complete response after radiotherapy. Thus, whether or not the tumor and node respond to induction chemotherapy was predictive of the response to subsequent radiotherapy (p<0.0005 in tumor, p<0.0001 in node). By reanalyzing according to disease subsets (i.e. primary site, T-stage, N-stage) this relationship was not observed at T1-T2 disease (p>0.3). Therefore the tumor or node's response to induction chemotherapy is a predictor for subsequent radiotherapy except in T1-T2 tumors, and complete response to radiotherapy can be expected despite the failure of induction chemotherapy in $T_1-T_2$ tumors.

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Cellular Antioxidant Activity and Whitening Effects of Dendropanax morbifera Leaf Extracts (황칠나무 잎 추출물의 세포 항산화 활성과 미백활성 측정)

  • Park, Su Ah;Park, Jun;Park, Chan Il;Jie, Young Jong;Hwang, Yun Chan;Kim, Yong Hyun;Jeon, So Ha;Lee, Hye Mi;Ha, Ji Hoon;Kim, Kyeong Jin;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.41 no.4
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    • pp.407-415
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    • 2013
  • In this study, we investigated the antioxidant activities on HaCaT and the whitening effects on B16F1 melanoma cells of Dendropanax morbifera leaf extract. In an antioxidative activity assay using HaCaT cells, the ethyl acetate ($50{\mu}g/ml$) and aglycone fractions ($25{\mu}g/ml$) of the D. morbifera leaf extract didn't exhibit any characteristics of cytotoxicity. When HaCaT cells were exposed to a single large dose ($800mJ/cm^2$) of UVB, the extracts protected the cells against UVB radiation. When HaCaT cells were treated with 10 mM $H_2O_2$ and $4{\mu}M$ rose bengal, the ethyl acetate ($6.25{\sim}50{\mu}g/ml$) and aglycone ($6.25{\sim}25{\mu}g/ml$) fractions protected the cells against oxidative damage in a concentration dependent manner. When the whitening effects of D. morbifera leaf extract were tested in melanoma B16/F1 cells treated with the a-melanocyte stimulating hormone (${\alpha}$-MSH), the extracts inhibited ${\alpha}$-MSH-stimulated intra/extracellular melanogenesis in a concentration dependent manner. The inhibitory effects of the ethyl acetate and aglycone fractions of D. morbifera leaf extract were 21% and 44% at $25{\mu}g/ml$, respectively. Both are more effective than arbutin (15% at $25{\mu}g/ml$) which is known as a whitening agent. These results indicate that fractions of the D. morbifera leaf can function as cell protectants and natural antioxidants in biological systems, particularly skins exposed to UV radiation by quenching and/or scavenging $^1O_2$ and other ROS, and protecting cells against ROS. In addition, fractions of the D. morbifera leaf can be applied to new whitening cosmetics because of their inhibitory effects on ${\alpha}$-MSH stimulated melanogenesis in B16F1 melanoma cells.

Cellular Protective Effect and Liposome Formulation for Enhanced Transdermal Delivery of Persicaria hydropiper L. Extract (여뀌 추출물의 세포 보호 작용과 피부 흡수 증진을 위한 리포좀 제형 연구)

  • Kim, Jung-Eun;Lee, Hye-Jin;Lim, Myoung-Sun;Park, Min-A;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.1
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    • pp.15-31
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    • 2012
  • In our previous studies, the antioxidant, anti-aging, and antibacterial activities of Persicaria hydropipier L. extract, and the moisturizing effect of cream containing P. hydropipier extract were investigated. In this study, the cellular protective effects of P. hydropipier extract and isoquercitrin, main component from P. hydropipier in $^1O_2$-induced photohemolysis of human erythrocytes and ultraviolet B (UVB)-exposed HaCaT cells were investigated. Liposomes such as ethosome and elastic liposome for enhanced transdermal delivery were prepared. Size, loading efficiency, stability, and cumulative permeated amounts of ethosomes and elastic liposomes were evaluated. P. hydropipier extract and isoquercitrin showed more prominent cellular protective effect than (+)-${\alpha}$-tocopherol, known as lipid antioxidant at $5{\mu}g/mL$. P. hydropipier extract didn't show any characteristics of cytotoxicity at $50{\mu}g/mL$. When HaCaT cells were exposed to a single large dose ($400mJ/cm^2$) of UVB, the extract protected the cells against UVB radiation in a concentration dependent manner ($12.5{\sim}50{\mu}g/mL$). Cell viability of HaCaT cells exposed to UVB $400mJ/cm^2$ was increased by treatment with P. hydropipier extract or isoquercitrin from 36 % (cell viability of positve control groups) to 90 % (cell viability of P. hydropipier extract or isoquercitrin- treated groups). The size of 0.04 % P. hydropiper extract loaded ethosomes was 173.0 nm and the loading efficiency was 55.58 %. 0.04 % P. hydropiper extract loaded ethosomes were stable with as monodisperse particles for 1 week. The ethosome exhibited more skin permeability than general liposome and ethanol solution. The optimal ratio of lipid to surfactant ($Tego^{(R)}$ care 450) of 0.1 % P. hydropiper extract loaded elastic liposomes was observed to be 95 : 5. Vesicle size of 0.1 % P. hydropiper extract loaded elastic liposome was 176.5 nm. The deformability index of the elastic liposome was 16.4. The loading efficiency was 68.8 %. The elastic liposome containing P. hydropiper extract showed more skin permeability than liposome without surfactant ($Tego^{(R)}$ care 450).

Prophylactic Cranial Irradiation for Acute Lymphoblastic Leukemia in Childhood (소아 급성 림프모구성 백혈병의 예방적 전뇌 방사선조사)

  • Kim, In-Ah;Choi, Ihl-Bhong;Kang, Ki-Mun;Shinn, Kyung-Sub;Kim, Hack-Ki
    • Radiation Oncology Journal
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    • v.14 no.2
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    • pp.137-147
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    • 1996
  • Purpose : This report is the result f retrospective analysis for children who received prophylactic cranial irradiation combined with intrathecal chemotherapy. Materials and Methods : Ninety children with ALL who had got bone marrow remission after induction chemotherapy received PCI. All but 3 children were treated with a dose of 1800 cGy as a standard regimen. While the PCI was given, all patients received intrathecal chemotherapy. Results : Nine of 90 patients experienced CNS relapse during the duration of follow-up ranged from 36 to 96 months (median 60 months). Three children experienced BM relapse prior to CNS relapse. Therefore, CNS relapse rate as the first adverse event was $6.7\%$. Median time interval of CNS relapse was 16 months from the first day of hematologic complete remission. Eighty-nine percent of patients who had CNS relapse were associated with hematologic relapse. and $78\%$ of CNS relpase occurred during maintenance chemotherapy (on-therapy relapse). The CNS RFS at 2 and 5 years are $68\%$ and $42\%$, respectively with median of 43 months. The Prognostic factors affecting CNS RFS are initial WBC count (cut-off point of 50,000/ul), FAB subtype and CALGB risk criteria. The DFS at 2 and 5 years are 61 and $39\%$, respectively with median of 34 months. The prognostic factors affecting DFS are initial WBC count (cut-off point of 50,000/ul), FAB subtype, POG and CALGB risk criteria. Conclusions : In our study, $6.7\%$ of CNS relapse rate as a first adverse event was comparable with other studies. Various risk criteria was based on age at diagnosis and initial WBC count such as POG and CALGB criteria, had prognostic significance for CNS RFS and DFS. Prospective randomized trial according to prognostic subgroup based on risk criteria and systematic study about neuropsychologic function for long term survivors, are essential to determine the most effective and least toxic form of CNS prophylaxis.

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Antioxidant and Neuroprotective Effects of Green Tea Seed Shell Ethanol Extracts (녹차씨껍질 에탄올 추출물의 항산화 활성 및 신경세포 보호 효과)

  • Sung, Nak-Yun;Song, Hayeon;Ahn, Dong-Hyun;Yoo, Yung-Choon;Byun, Eui-Baek;Jang, Beom-Su;Park, Chulhwan;Park, Won-Jong;Byun, Eui-Hong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.958-965
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    • 2016
  • The objective of this study was to evaluate the antioxidant activity of green tea seed shell as an industrial byproduct. Green tea seed shell extract (GTSSE) was obtained by ethanol extraction, and the yield was $1.4{\pm}0.22%$. The radical scavenging activities [1,1-diphenyl-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)], xanthine oxidase inhibition activity, and reducing power of GTSSE dose-dependently increased. To estimate the neuroprotective effect of GTSSE, viability was tested in HT22 mouse hippocampal cells. GTSSE treatment induced cytotoxicity at a concentration higher than $100{\mu}g/mL$ but not at a concentration lower than $50{\mu}g/mL$. Using this optimal concentration range, GTSSE treatment significantly increased cell viability in $H_2O_2$-treated HT22 cells. Further, GTSSE treatment increased superoxide dismutase activity and decreased the malonaldehyde level, a product of lipid peroxidation, in HT22 cells. Therefore, these results indicate that green tea seed shell extract may be useful for the development of antioxidant materials and have potential activity to prevent and treat neuro-degenerative diseases such as Alzheimer's disease.

Calculation of Derived Investigation Levels for Uranium Intake (우라늄 섭취의 유도조사준위 산출)

  • Lee, Na-Rae;Han, Seung-Jae;Cho, Kun-Woo;Jeong, Kyu-Hwan;Lee, Dong-Myung
    • Journal of Radiation Protection and Research
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    • v.38 no.2
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    • pp.68-77
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    • 2013
  • Derived Investigation levels(DILs) were calculated to protect the workers from the effects of both radiological hazard and chemical toxicity by uranium intake. Investigation Levels(ILs) of committed effective dose of 2 mSv $y^{-1}-6$ mSv $y^{-1}$ and uranium concentration of 0.3 ${\mu}g$ $g^{-1}$ in kidney, based on Korean Nuclaer Safety Act, Korean Occupational Safety and Health Act and current scientific studies of uranium intake were assumed. DILs of radiological hazard and chemical toxicity were then calculated based on the concentration of uranium in air of workplace, the lung monitoring and urine analysis, respectively. As a result, in case of the nuclear fuel fabrication plant where 3.5% enriched uranium is handled, derived investigation level(DIL) for the control of the concentration of uranium in the air of workplace assumed with 15-min acute inhalation was 0.6 mg $m^{-3}$ for all types of uranium. DILs for the control of the average concentration of uranium in air of workplace, assuming an 8-hour workday, were 15.21 ${\mu}g$ $m^{-3}$ of Type F uranium, 0.41-1.23 Bq $m^{-3}$ and 0.13-0.39 Bq $m^{-3}$ for Type M and Type S uranium, respectively. DILs for the lung monitoring assumed with a period of 6-month interval were 0.37-1.11 Bq and 0.39-1.17 Bq in acute and chronic inhalation for Type M, respectively and 0.30- 0.91 Bq and 0.19-0.57 Bq in acute and chronic inhalation for Type S, respectively. Since a detection limit of typical germanium detector for the measurement of 235U activity is 4 Bq, DILs calculated for the lung monitoring were not appropriate. DILs for urine analysis, for which an interval was assumed to be 1 month, were 14.57 ${\mu}g$ $L^{-1}$ based on chemical toxicity after acute inhalation. In addition, acute and chronic inhalation of Type M were calculated 2.85-8.58 ${\mu}g$ $L^{-1}$ and 1.09-3.27 ${\mu}g$ $L^{-1}$ based on the radiological hazard, respectively.

Concurrent Docetaxel/Cisplatin and Thoracic Radiotherapy for Locally Advanced Non-Small Cell Lung Cancer (국소 진행성 비소세포 폐암에서 Docetaxel Cisplatin을 사용한 화학-방사선 동시치료의 효과)

  • Jang, Tae Won;Park, Jung Pil;Kim, Hee Kyoo;Ok, Chul Ho;Jeung, Tae Sig;Jung, Maan Hong
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.3
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    • pp.257-264
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    • 2004
  • Background : There are many combinations of treatment for locally advanced non-small cell lung cancer (NSCLC). Recent studies have showed the efficacy of concurrent chemoradiotherapy (CCRT) in NSCLC. At present, however, there is no consensus about the optimal dosages and timing of radiation and chemotherapeutic agents. The aims of study were to determine the feasibility, toxicity, response rate, and survival rate in locally advanced NSCLC patients treated with doxetaxel and cisplatin based CCRT. Method : Sixteen patients with unresectable stage III NSCLC were evaluated from May 2000 until September 2001. Induction chemoradiotherapy consisted of 3 cycles of docetaxel (75 $mg/m^2/IV$ on day 1) and cisplatin (60 $mg/m^2/IV$ on day 1) chemotherapy every 3 weeks and concomitant hyperfractionated chest irradiation (1.15 Gy/BID, total dose of 69 Gy) in 6 weeks. Patient who had complete or partial response, and stable disease were applied consolidation chemotherapy of docetaxel and cisplatin. Results : All patients showed response to CCRT. Four patients achieved complete response (25%), partial responses in 12 patients (75%). The major common toxicities were grade III or more of neutropenia (87.3%), grade III esophagitis (68.8%), pneumonia (18.8%) and grade III radiation pneumonitis (12.5%). Thirteen patients were ceased during follow-up period. Median survival time was 19.9 months (95% CI; 4.3-39.7 months). The survival rates in one, two, and three years are 68.7%, 43.7%, and 29.1%, respectively. Local recurrence was found in 11 patients (66.8%), bone metastasis in 2, and brain metastasis in 1 patient. Conclusion : The response rate and survival time of CCRT with docetaxel/cisplatin in locally advanced NSCLC were encouraging, but treatment related toxicities were high. Further modification of therapy seems to be warranted.

Development of Manual Multi-Leaf Collimator for Proton Therapy in National Cancer Center (국립암센터의 양성자 치료를 위한 수동형 다엽 콜리메이터 개발)

  • Lee, Nuri;Kim, Tae Yoon;Kang, Dong Yun;Choi, Jae Hyock;Jeong, Jong Hwi;Shin, Dongho;Lim, Young Kyung;Park, Jeonghoon;Kim, Tae Hyun;Lee, Se Byeong
    • Progress in Medical Physics
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    • v.26 no.4
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    • pp.250-257
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    • 2015
  • Multi-leaf collimator (MLC) systems are frequently used to deliver photon-based radiation, and allow conformal shaping of treatment beams. Many proton beam centers currently make use of aperture and snout systems, which involve use of a snout to shape and focus the proton beam, a brass aperture to modify field shape, and an acrylic compensator to modulate depth. However, it needs a lot of time and cost of preparing treatment, therefore, we developed the manual MLC for solving this problem. This study was carried out with the intent of designing an MLC system as an alternative to an aperture block system. Radio-activation and dose due to primary proton beam leakage and the presence of secondary neutrons were taken into account during these iterations. Analytical calculations were used to study the effects of leaf material on activation. We have fabricated tray model for adoption with a wobbling snout ($30{\times}40cm^2$) system which used uniform scanning beam. We designed the manual MLC and tray and can reduce the cost and time for treatment. After leakage test of new tray, we upgrade the tray with brass and made the safety tool. First, we have tested the radio-activation with usually brass and new brass for new manual MLC. It shows similar behavior and decay trend. In addition, we have measured the leakage test of a gantry with new tray and MLC tray, while we exposed the high energy with full modulation process on film dosimetry. The radiation leakage is less than 1%. From these results, we have developed the design of the tray and upgrade for safety. Through the radio-activation behavior, we figure out the proton beam leakage level of safety, where there detects the secondary particle, including neutron. After developing new design of the tray, it will be able to reduce the time and cost of proton treatment. Finally, we have applied in clinic test with original brass aperture and manual MLC and calculated the gamma index, 99.74% between them.

Study on the Physical Properties of the Gamma Beam-Irradiated Teflon-FEP and PET Film (Teflon-FEP 와 PET Film 의 감마선 조사에 따른 물리적 특성에 관한 연구)

  • 김성훈;김영진;이명자;전하정;이병용
    • Progress in Medical Physics
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    • v.9 no.1
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    • pp.11-21
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    • 1998
  • Circular metal electrodes were vacuum-deposited with chromium on the both sides of Teflon-FEP and PET film characteristic of electret and the physical properties of the two polymers were observed during an irradiation by gamma-ray from $\^$60/Co. With the onset of irradiation of output 25.0 cGy/min the induced current increased rapidly for 2 sec, reached a maximum, and subsequently decreased. A steady-state induced current was reached about in 60 second. The dielectric constant and conductivity of Teflon-FEP were changed from 2.15 to 18.0 and from l${\times}$l0$\^$-17/ to 1.57${\times}$10$\^$-13/ $\Omega$-$\^$-1/cm$\^$-1/, respectively. For PET the dielectric constant was changed from 3 to 18.3 and the conductivity from 10$\^$-17/ to 1.65${\times}$10$\^$-13/ $\Omega$-$\^$-1/cm$\^$-1/. The increase of the radiation-induced steady state current I$\^$c/, permittivity $\varepsilon$ and conductivity $\sigma$ with output(4.0 cGy/min, 8.5 cGy/min, 15.6 cGy/min, 19.3 cGy/min) was observed. A series of independent measurements were also performed to evaluate reproducibility and revealed less than 1% deviation in a day and 3% deviation in a long term. Charge and current showed the dependence on the interval between measurements, the smaller the interval was, the bigger the difference between initial reading and next reading was. At least in 20 minutes of next reading reached an initial value. It may indicate that the polymers were exhibiting an electret state for a while. These results can be explained by the internal polarization associated with the production of electron-hole pairs by secondary electrons, the change of conductivity and the equilibrium due to recombination etc. Heating to the sample made the reading value increase in a short time, it may be interpreted that the internal polarization was released due to heating and it contributed the number of charge carriers to increase when the samples was again irradiated. The linearity and reproducibility of the samples with the applied voltage and absorbed dose and a large amount of charge measured per unit volume compared with the other chambers give the feasibility of a radiation detector and make it possible to reduce the volume of a detector.

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The Effects of Vitamin C on the Activity of Liver Enzymes and Hepatic Damage in Rats Treated with Radiation and Aflatoxin $B_1$ (Vitamin C가 방사선과 Aflatoxin $B_1$을 투여한 흰쥐의 간 기능 효소 활성 및 간 손상에 미치는 효과)

  • Kang, Jin-Soon
    • The Korean Journal of Food And Nutrition
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    • v.23 no.1
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    • pp.30-38
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    • 2010
  • This study was conducted to determine the effects of vitamin C on the activity of liver function enzymes and electromicrographic changes in white rats treated with aflatoxin $B_1(AFB_1)$ or X-ray and $AFB_1$. Six week-old male Sprague-Dawley rats were randomly divided into five groups: a control group, $AFB_1$ treated group, $AFB_1$ treated group with vitamin C, X-ray and $AFB_1$ co-treated group, X-ray and $AFB_1$ co-treated group with vitamin C. On the first day of the experiment, only one dose of X-rays was exposed to the entire liver at 1,500 cGy. Next, vitamin C was injected at 10 mg/kg body weight by intraperitoneal injection, followed 1 hr later by the administration of 0.4 mg/kg of $AFB_1$ by intraperitoneal injection. These treatments were then administered every three days over a period of 15 days. On the 16th day of treatments, the animals were sacrificed. Analysis of the activity of the liver function enzymes, GOT, ALK phatase and LDH, in the sera of rats revealed that they were somewhat increased by $AFB_1$ treatment, X-ray and $AFB_1$ co-treatment when compared to the control group. Furthermore, the activity of these enzymes decreased in response to administration of vitamin C. Especially, the levels of GOT were remarkably decreased in the $AFB_1$ treated group treated with vitamin C when compared to the group treated with $AFB_1$ alone(p<0.001). Electromicrographic analysis revealed cloudy swelling, necrosis, vesicular degeneration and fat accumulation of hepatocytes in response to treatment with $AFB_1$ or co-treatment with X-ray and $AFB_1$. However, the destruction of hepatic cells was considerably lower in the vitamin C-treated group. These results indicate that vitamin C had ameliorating effects on the hepatic cell damage.