• Title/Summary/Keyword: Lethal concentration

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Efficacy Study of Osteradionecrosis Using Fibrin and SDF-1 (피브린과 SDF-1을 사용한 방사성뼈괴사의 효용성연구)

  • Hong-Moon, Jung
    • Journal of the Korean Society of Radiology
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    • v.16 no.6
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    • pp.799-805
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    • 2022
  • Radiation therapy of human tissues, including bone tissue, is accompanied by side effects on normal tissues. It has a more lethal effect on stem cells, which play an essential role in tissue regeneration, including the basal cells constituting the tissue. In this study, the mouse parietal model, which implemented an artificial osteoradionecrosis model on the parietal region of the mouse, was artificially defected and then the bone regeneration was tested. In order to overcome the implemented osteoradionecrosis, a fibrin scaffold, widely used as a biomaterial, and stromal cell-derived factor-1 (SDF-1), which is used as a long-term treatment for damaged, were mixed to verify the osteoradionecrosis regeneration effect on the parietal of mouse. In order to expect a synergistic effect in the fibrin scaffolds, a fibrin scaffolds was prepared after maintaining the concentration of SDF-1 (1 ㎍/ml) in the fibrinogen solution. In this study, after artificially creating a osteoradionecrosis model in the parietal region of mouse, fibrin scaffolds were incorporated to analyze the effect of bone regeneration within 4 weeks, the initial stage of bone regeneration. In conclusion, the combined use of these two substances did not show a dramatic regenerative effect in inducing the regeneration of osteoradionecrosis in the parietal region of mouse. However, positive results were obtained that can be maintain the bone regeneration effect environment at the initial stage. Therefore, the combined use of the fibrin scaffold and SDF-1 is considered to be a suitable candidate for the effect of overcoming osteoradionecrosis.

Antiviral effects of Bovine antimicrobial peptide against TGEV in vivo and in vitro

  • Liang, Xiuli;Zhang, Xiaojun;Lian, Kaiqi;Tian, Xiuhua;Zhang, Mingliang;Wang, Shiqiong;Chen, Cheng;Nie, Cunxi;Pan, Yun;Han, Fangfang;Wei, Zhanyong;Zhang, Wenju
    • Journal of Veterinary Science
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    • v.21 no.5
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    • pp.80.1-80.13
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    • 2020
  • Background: In suckling piglets, transmissible gastroenteritis virus (TGEV) causes lethal diarrhea accompanied by high infection and mortality rates, leading to considerable economic losses. This study explored methods of preventing or inhibiting their production. Bovine antimicrobial peptide-13 (APB-13) has antibacterial, antiviral, and immune functions. Objectives: This study analyzed the efficacy of APB-13 against TGEV through in vivo and in vitro experiments. Methods: The effects of APB-13 toxicity and virus inhibition rate on swine testicular (ST) cells were detected using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT). The impact of APB-13 on virus replication was examined through the 50% tissue culture infective dose (TCID50). The mRNA and protein levels were investigated by real-time quantitative polymerase chain reaction and western blot (WB). Tissue sections were used to detect intestinal morphological development. Results: The safe and effective concentration range of APB-13 on ST cells ranged from 0 to 62.5 ㎍/mL, and the highest viral inhibitory rate of APB-13 was 74.1%. The log10TCID50 of 62.5 ㎍/mL APB-13 was 3.63 lower than that of the virus control. The mRNA and protein expression at 62.5 ㎍/mL APB-13 was significantly lower than that of the virus control at 24 hpi. Piglets in the APB-13 group showed significantly lower viral shedding than that in the virus control group, and the pathological tissue sections of the jejunum morphology revealed significant differences between the groups. Conclusions: APB-13 exhibited good antiviral effects on TGEV in vivo and in vitro.

A Study on the Hazard Area of Bunkering for Ammonia Fueled Vessel (암모니아 연료추진 선박의 벙커링 누출 영향에 관한 연구)

  • Ilsup Shin;Jeongmin Cheon;Jihyun Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.964-970
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    • 2023
  • As part of the International Maritime Organization ef orts to reduce greenhouse gas emissions, the maritime industry is exploring low-carbon fuels such as liquefied natural gas and methanol, as well as zero-carbon fuels such as hydrogen and ammonia, evaluating them as environmentally friendly alternatives. Particularly, ammonia has substantial operational experience as cargo on transport ships, and ammonia ship engines are expected to be available in the second half of 2024, making it relatively accessible for commercial use. However, overcoming the toxicity challenges associated with using ammonia as a fuel is imperative. Detection is possible at levels as low as 5 ppm through olfactory senses, and exposure to concentrations exceeding 300 ppm for more than 30 min can result in irreparable harm. Using the KORA program provided by the Chemical Safety Agency, an assessment of the potential risks arising from leaks during ammonia bunkering was conducted. A 1-min leak could lead to a 5 ppm impact within a radius of approximately 7.5 km, affecting key areas in Busan, a major city. Furthermore, the potentially lethal concentration of 300 ppm could have severe consequences in densely populated areas and schools near the bunkering site. Therefore, given the absence of regulations related to ammonia bunkering, the potential for widespread toxicity from even minor leaks highlights the requirement for the development of legislation. Establishing an integrated system involving local governments, fire departments, and environmental agencies is crucial for addressing the potential impacts and ensuring the safety of ammonia bunkering operations.

Evaluation of Fish Acute Toxicity and Preliminary Risk Assessment of Plant Extracts, Sophora, Neem and Derris (유기농업자재 고삼, 님 및 데리스 추출물의 어류에 대한 독성과 위해성 평가)

  • Park, Kyung-Hun;Oh, Jin-A;Paik, Min-Kyoung;Son, Mi-Yeon;Lim, Joung-Taek;Jin, Jung-hwa;Hong, Soonsung;Cho, Nam-jun;Han, Sang-Gyun;Kim, Byung-Seok
    • The Korean Journal of Pesticide Science
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    • v.19 no.3
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    • pp.255-263
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    • 2015
  • Promoting the organic farming, much of the plant extracts used for controlling pests and fungi have been imported from China, India and Myanmar. But, it is so worrisome that aquatic animals such as muddy loach inhabiting in paddy field and common carps in river exposed to the pests and fungi likely be harmed. This study was conducted in order to evaluate the risks of aquatic animals influenced by the three plant extracts, i.e. Sophora flavescens, Azadirachta indica and Derris elliptica. The toxicities of common carp (Cyprinus Carpio), muddy loach (Misgurnus anguillicaudatus) and PEC (Predicted environmental concentration) exposed to the three plant extracts were estimated by the typical spray volume method. Risks were determined by the toxicity value as 48-hr $LC_{50}$ (Lethal concentration, median) or NOEC (No observed effect concentration) into PEC. 48-hr $LC_{50}$ of Common carp and NOEC by Sophora flavescens extracts was 7.9 and 6.2 mg/L, 26.8 and 21.8 mg/L by Azadirachta indica extracts and 47.0 and < 24.0 mg/L by Derris elliptica extracts, respectively. 48-hr $LC_{50}$ of Muddy loach and NOEC by Sophora flavescens extracts was 16.9 and 10.0 mg/L, 35.6 and 30.0 mg/L by Azadirachta indica extracts, and 73.9 and < 40 mg/L by Derris elliptica extracts, respectively. Therefore, acute toxicities of the three plant extracts for aquatic animals were proved to be very low level. PEC of Sophora flavescens extracts in paddy, drainage and river water was 68.0~3.0, 11.33~0.50 and 3.0~0.0018 mg/L, respectively. TER of Sophora flavescens extracts in the three water was 0.2~5.6, 1.5~33.8 and 2.6~4388.9, respectively. PEC of Azadirachta indica extracts in paddy, drainage and river water was 90.9~1.2, 15.2~0.2 and 4.8~0.00075 mg/L, respectively. TER of Azadirachta indica extracts in the three water was 0.4~29.7, 2.3~178.0 and 4.5~35733.3, respectively. PEC of Derris elliptica extracts in river water was 0.0063 mg/L. TER of Derris elliptica extracts in river water was 5222~15667.

Control of Kimchi Fermentation by the Addition of Natural Antimicrobial Agents Originated from Plants (식물유래 천연항균물질 첨가에 의한 김치의 발효조절)

  • Seo, Hyun-Sun;Kim, Seonhwa;Kim, Jinsol;Han, Jaejoon;Ryu, Jee-Hoon
    • Korean Journal of Food Science and Technology
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    • v.45 no.5
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    • pp.583-589
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    • 2013
  • We investigated the delay of kimchi fermentation by the addition of plant extracts. Fifteen plant extracts were screened for inhibitory activity aginst Lactobacillus plantarum by using an agar well diffusion assay, and determined the minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were determined. The lowest MIC for grapefruit seed extract (GFSE; 0.0313 mg/mL) was determined, followed by Caesalpinia sappan L. extract (CSLE; 0.25 mg/mL), and oregano essential oil (OREO; 1.0 mg/mL). GFSE, CSLE, and OREO were individually added to kimchi, and incubated the samples at 10 for up to 20 days. Results showed that the addition of GFSE (0.3 and 0.5%), CSLE (0.1, 0.3, and 0.5%), or OREO (0.5 and 1.0%) led to a significant increase in the pH of kimchi, and also a significant reduction in the numbers of lactic acid bacteria. Taken together, the addition of natural antimicrobial agents can delay kimchi fermentation.

Effect of X-Irradiation on the Levels of some Sulfhydryl Groups, Protein and Cell Volume of Ehrlich Ascites Tumour Cells (X-선(線) 조사(照射)가 Ehrlich 암세포(癌細胞)의 용적(容積), 단백양(蛋白量) 및 수종(數種) Sulfhydryl 기(基)에 미치는 영향(影響)에 관(關)하여)

  • Yu, Choon-Shik;Choo, Young-Eun
    • The Korean Journal of Physiology
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    • v.3 no.2
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    • pp.9-16
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    • 1969
  • It is well known that a number of -SH and -SS containing substances afford a certain measure of protection against radiation effects in many biological systems, and it is conceivable that inherent -SH levels in Ehrlich ascites tumour (ELD)cells may be of decisive improtance with respect to the development of cellular radiation injury. So far, little effort has been directed to elucidate the changes in levels of different -SH and -SS groups in ELD cells when the tumour-bearing whole animal was subjected to the sublethal dose of X-irradiation. The present study was designed to bring some lights in the possible changes of and relationship between various sulfhydryl levels, such as P-SH, NP-SH and NP-SS, as well as the content of protein and cell volume of ELD cells, after subjecting the ELD mice to 1,200 r of X-irradiation. The animals used in this experiment were all mixed bred mice of $20{\sim}25\;gm$ in body weight (approximately 2 months old) irrespective of sex. 12 mice in one experiment were inoculated intraperitoneally with 0.2 ml of ascites tumour cells $(2{\times}10^6\;cells)$, and on the 7th day of the tumour growth, they were X-irradiated with 1,200 r, using the conventional X-ray machine under the following conditions: 200 Kv at 15 mA, 0.5 mm Cu filter, target-skin distance: 50 cm. Radiation dose was measured with the the Philip integrating dosimeter. At 24, 36, 48 and 60 hours after the X-irradiation, the mice were killed by cervical dislocation, and the tumours were taken out. Freshly withdrawn ascites tumours were placed in ice, and immediately the cell concentration was measured with the Coulter Cell Counter (Model B), and the hematocrit of the tumour cells were also determined. Cell volume was thus calculated by the cell concentration and hematocrit value. P-SH content of ELD cells was measured potentiometrically according to the method of Calcutt & Doxey, and NP-SH and NP-SS contents were measured spectrophotometrically by the method described by Ellman. Protein content of ELD cells was determined with the Folin phenol reagent by Lowry et al. Altogether, 48 experimental mice were used, and 12 mice with the only exception of X-irradiation were used as the control. Results obtained indicate that the contents of all the cellular sulfhydryl groups as well as cell volume and protein content of the ELD cells increase significantly as time progresses after the sub-lethal X-ray dose of 1,200 r was given and that all the increase is in a lineal fashion. The regression lines of the relative values, (i. e., taking each control value as 1) of all the values obtained, and the regression lines of cell volume, protein and NP-SH are identical, whereas those of NP-SS and P-SH appear to be widely seperated. However, the difference of those two lines (NP-SS & P-SH) were found to be not significant statistically (p>0.05). Therefore, it can be concluded from the above results that all the values examined increase in a lineal fashion with no statistically significant difference among them. Also, with the radiation dose of 1,200 r, the ELD cell becomes enlarged and swollen progressively up to 60 hours post-irradiation and it becomes more than two times of the original normal size at 60 hours after the irradiation, and up to this stage, it seems apparent that the cell division has been slow due to the X-irradiation applied in this experiment. It is well understandable that the contents of NP-SH, NP-SS, P-SH and protein of the ELD cells increase in parallel with the increase of the cell volume by the X-ray does used, but it also seems interesting to note that all the cellular substances tested show no appreciable difference in the pattern of increase.

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Toxicity Evaluation of 'Bt-Plus' on Parasitoid and Predatory Natural Enemies (기생성 및 포식성 천적에 대한 작물보호제 '비티플러스'의 독성 평가)

  • Seo, Sam-Yeol;Srikanth, Koigoora;Kwon, Gi-Myon;Jang, Sin-Ae;Kim, Yong-Gyun
    • Korean journal of applied entomology
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    • v.51 no.1
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    • pp.47-58
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    • 2012
  • Effect of a new crop protectant 'Bt-Plus' on natural enemies was analyzed in this study. Tested natural enemies included two parasitic species of $Aphidius$ $colemani$ and $Eretmocerus$ $eremicus$, and four predatory species of $Harmonia$ $axyridis$, $Orius$ $laevigatus$, $Amblyseius$ $swirskii$, and $Phytoseiulus$ $persimilis$. 'Bt-Plus' was formulated by combination of three entomopathogenic bacteria ($Xenorhabdus$ $nematophila$ (Xn), $Photorhabdus$ $temperata$ subsp. $temperata$ (Ptt), $Bacillus$ $thuringiensis$ (Bt)) and bacterial metabolite (BM). All three types of 'Bt-Plus' showed significantly higher toxicities against fourth instar $Plutella$ $xylostella$ larvae than Bt single treatment. Two types of bacterial mixtures ('Xn+Bt' and 'Ptt+Bt') showed little toxicity to all natural enemies in both contact and oral feeding assays. However, 'BM+Bt' showed significant toxicities especially to two predatory mites of $A.$ $swirskii$ and $P.$ $persimilis$. The acaricidal effects of different bacterial metabolites were evaluated against two spotted spider mite, $Tetranychus$ $urticae$. All six BM chemicals showed significant acaricidal effects. The BM mixture used to prepare 'Bt-Plus' showed a high acaricidal activity with a median lethal concentration at 218.7 ppm (95% confidence interval: 163.2 - 262.3). These toxic effects of bacterial metabolites were also proved by cytotoxicity test against Sf9 cells. Especially, benzylideneacetone, which was used as a main ingredient of 'BM+Bt', showed high cytotoxicity at its low micromolar concentration.

Mitigation Effect of Drought Stress by Plant Growth-promoting Bacterium Bacillus sp. SB19 on Kale Seedlings in Greenhouse (식물생장촉진 Bacillus sp. SB19 균주의 케일 처리에 대한 가뭄 스트레스 완화 효과)

  • Kim, Dayeon;Lee, Sang-Yeob;Kim, Jung-Jun;Han, Ji-Hee
    • Korean Journal of Organic Agriculture
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    • v.24 no.4
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    • pp.833-847
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    • 2016
  • Drought stress is a major agricultural limitation to crop productivity worldwide, especially by which leafy vegetables, plant leaves eaten as vegetable, could be more lethal. The study was carried out to know the effect of drought tolerance plant growth promoting bacteria (PGPB) on water stress of kale seedlings. A total of 146 morphologically distinct bacterial colonies were isolated from bulk soil and rhizosphere soil of leafy vegetables and screened for plant growth promoting microbioassay in greenhouse. Out of them the isolate SB19 significantly promoted the growth of kale seedlings in increasement of about 42% of plant height (14.1 cm), 148% of leaf area ($19.0cm^2$) and 138% of shoot fresh weight (1662.5 mg) attained by the bacterially treated plants compared to distilled water treated control (9.9 cm, $7.7cm^2$, 698.8 mg). Shoot water content of SB19 treated kale seedlings (1393.8 mg) was also increased about 152% compared with control (552.5 mg). The SB19 isolated from bulk soil of kale plant in Iksan, Korea, was identified as species of Bacillus based on 16S rRNA gene sequencing analysis. We evaluated the effect of drought tolerance by the Bacillus sp. SB19 on kale seedlings at 7th and 14th days following the onset of the water stress and watering was only at 7th day in the middle of test. In the survey of 7th and 14th day, there were mitigation effect of drought stress in kale seedlings treated with $10^6$ and $10^7cell\;mL^{-1}$ of SB19 compared to distilled water treated control. Especially, there were more effective mitigation of drought damage in kale seedlings treated with $10^7cell\;mL^{-1}$ than $10^6cell\;mL^{-1}$. Further, although drought injury of bacterially treated kale seedlings were not improved at 14th day compared with 7th day, drought injury of $10^7cell\;mL^{-1}$ of SB19 treated kale seedlings were not happen rapidly but developed over a longer period of time than $10^6cell\;mL^{-1}$ of SB19 or control. The diffidence of results might be caused by the concentration of bacterial suspension. This study suggests that beneficial plant-microbe interaction could be a important role of enhancement of water availability and also provide a good method for improving quality of leafy vegetables under water stress conditions.

Pathogenicity bioassay of entomopathogenic nematode, Steinernema carpocapsae GSN1 strain (Nematoda: Steinernematidae) on the shiitake fungus moth, Morophagoides moriutii (Lepidoptera: Tineidae) (표고버섯좀나방에 대한 곤충병원성 선충의 병원성 검정)

  • Kim, Hyeong Hwan;Kim, Dong Hwan;Cho, Myung Rae;Yang, Chang Yeol;Kang, Taek Jun;Jeon, Sung Wook;Song, Jin Sun;Jung, Young Hak;Park, Hae Woong;Park, Chung Gyoo;Choo, Ho Yul
    • Journal of Mushroom
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    • v.12 no.4
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    • pp.357-362
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    • 2014
  • Pathogenicity of Steinernema carpocapsae GSN1 strain was evaluated against Morophagoides moriutii larvae. In Petridish tests, insect mortality by the nematode was dose dependent, which increased with dose from 5 to 160 infective juveniles(IJs)/larva. Pathogenicity against fourth-instar larvae was higher than the rate of corresponding second- and third-instar larvae, showing 100% insect mortality with the dose of 40 IJs/$4^{th}$ instar larva and 80 IJs/$2^{nd}$ or $3^{rd}$ instar larvae. Lethal concentration values at 50% ($LC_{50}$) of S. carpocapsae GSN1 strain were 4.2 IJs/$2^{nd}$ instar larva; 8.5 IJs/$3^{rd}$ instar larva; and 2.3 IJs/$4^{th}$ instar larva, respectively. The number of nematodes established in M. moriutii larvae after infection increased in the increment of dose and insect developmental stage. The highest number of nematodes was harvested from fourth instar larvae of M. moriutii at a dose of 160 IJs per larva, showing 22.5 nematodes per insect larva. Nematode reproductive capacity was related to insect developmental stage, showing 6,335 IJs/$2^{nd}$ instar larva, 21,660 IJs/$3^{rd}$ instar larvae, and 88,700 IJs/$4^{th}$ instar larvae.

Hemopoietic and Radioprotective Effects of Shenrong Fuzheng Tang(S.F.T.;蔘茸扶正湯) (삼용부정탕(蔘茸扶正湯)의 방사선(放射線) 조사(照射)로 손상(損傷)된 조직(組織) 회부(恢復) 및 조혈촉진(造血促進) 효과(效果))

  • Kim, Jeong-Su;Choe, Seung-Hun;An, Gyu-Seok
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.3 no.1
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    • pp.129-147
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    • 1997
  • Radiotherapy is an irreplaceable method of cancer treatment. But it has several side effects, especially damages to the hemopoietic and Immune system. Therefore radioprotectors are required to treat cancer successfully. A lot of Herbs and Herbal prescriptions are reported to have radioprotective effects. Above all, those to support the healthy energy and strengthen the body resistance are found more effective. This study was performed to evaluate the radioprotective effects of prescription Shenrong Fuzheng Tang(S.F.T.), which consists of 16 kinds of herbs. We investigated proliferation of murine splenocytes, secretion of colony-stimulating-factors(CSFs), immunocompetence after irradiation in-vitro, and Endogenous spleen colony assay, survival assay in-vivo. When splenocytes were cultured with Shenrong Fuzheng $Tang(S.F.T.)(500{\mu}g/ml)$, proliferation was enhanced 5.7 times compared to control cultured with medium alone(p<0.05) and, showed highest proliferation at 4th day after incubation. In order to evaluate stimulation of hemopoiesis of Shenrong Fuzheng Tang(S.F.T.), the supernatant of splenocytes cultured with optimal concentration of Shenrong Fuzheng Tang(S.F.T.) was used to measure CSFs secretion. The result showed enhanced secretion of colony-stimulating-factors (CSFs) compared to control(p<0.05). To evaluate the protective effect of lymphocytes from irradiation, proliferation of splenocytes stimulated by LPS and ConA after incubation with Shenrong Fuzheng Tang(S.F.T.) for 24h Prior to Irradiation$(1{\sim}3\;Gy)$ was measured. The results showed higher proliferation of Shenrong Fuzheng Tang(S.F.T.) treated cells than that of non-treated cells. And percentage increases of irradiated splenocytes per non-irradiated splenocytes were also higher in Shenrong Fuzheng Tang (S.F.T.)-treated cells than control. Endogenous spleen colony assay. to evaluate the protection of hemopoietic cells from irradiation, showed increased number of colonies(p=0.03) in Shenrong Fuzheng Tang(S.F.T.) treated murine spleen$(10.3{\pm}1.9)$ compared to non-treated murine spleen$(3.4{\pm}0.8)$. Survival time of mice irradiated with lethal dose of ${\gamma}-ray(9Gy)$ was prolonged in Shenrong Fuzheng Tang(S.F.T.) treated group prior to irradiation as compared to non-treated group. According to these results we can suggest that prescription Shenrong Fuzheng Tang(S.F.T.) has radioprotective effects and can be used to protect the hemopoietic and immune system from damages of anti-cancer radiotherapy.

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