• Title/Summary/Keyword: Dose-rate effects

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Effect of Inhibitor of Nitric Oxide Synthesis on the Ischemic Reconditioning in Isolated Heart of Rat. (NO 억제제가 허혈전처치의 심장 보호효과에 미치는 영향)

  • 유호진;조은용
    • Journal of Chest Surgery
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    • v.29 no.8
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    • pp.807-815
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    • 1996
  • The protective effect of'ischemic preconditioning'on ischemid-reperfusion injury of heart has been reported in various animal species. but without known mechAnism in detail, In An attempt to investigate the cardioprotective mechanism of ischemic preconditioning, we examined the effects of nitric oxide(UO) synthesis in preconditioned heart of rat The isolated hearts perfused by Langendorfr's method were ex- posed to 30min global ischemia followed by 30min reperfusion with oxygenated Krebs-Henseleit(K-H) sol- ution. Ischemic preconditioning was performed with three episodes of Sm n ischemia and Smin repeyfusion before the induction of prolong ischemia(30min)-reperfusion(30min). Ischemic preconditioning prevented the depression of cardiac function(left ventricular pressure .K heart rate) observed in the ischemia- reperfusion hearts and reduced the release of lactate dehydrogenase during the reperfusion period. On electromicroscopic pictures, myocardial ultrastructures wore relatively well preserved in isthemic preconditioned hearts. N6_nitro-L-arginine methyl ester(L-NAME) an inhibitor of L-arginine citric oxide pathway, was infused at a rate O.Smllmin In a dose of 10mg kg-1 before the initial ischemic preconditioning. neither the protection of cardiac function nor the reduction of LDH releAse in ischemic preconditioning hearts was altered in the presence of added L-NAME On ultrastructural finding, the preservation of morphology in ischemic preconditioning heart was not change by the pretreatment of L-UAME. The failure of the WO synthesis inhibitor to reduce t e effect of ischemic preconditioning may be related to be species specific in that NO may allot be the trigger for ischemic preconditioning in rats.

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The Effects of Mixer Geometry on Hydraulic Turbulence : Computational Modeling (3-D 전산유체를 이용한 급속혼화조 형상에 따른 난류 유동장 연구)

  • Park, No-Suk;Kim, Sung-Hoon;Park, Heekyung
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1173-1182
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    • 2000
  • The rapid mixing process has been considered as an important step in water treatment. Since the coagulant dispersion into raw water by rapid mixer can influence on the flocculation and filtration efficiency, many researchers have developed various devices and mixing methodologies. Until now, they focused attention on only coagulant dose, pH. rotating velocity and G value but overlooked the real turbulent flow and mixer geometry in rapid mixer. Therefore this paper questions the significance of turbulent flows in rapid mixer and focuses on the analysis of turbulent fluid in various mixer geometry with CFD(Computational Fluid Dynamics). The results of the jar-tests using various geometries indicate that the turbidity removal rate in a circular jar without baffle is higher than that of a circular with baffle. And the turbidity removal rate in Hudson jar is also founded to be higher than in the circular jar with baffle. The CFD simulation of velocity fields in jar demonstrates that the differences of removal rates among the various geometries are largely due to the formation of the different turbulent fluids fields with different geometries.

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Screening for the 3' UTR Polymorphism of the PXR Gene in South Indian Breast Cancer Patients and its Potential role in Pharmacogenomics

  • Revathidevi, Sundaramoorthy;Sudesh, Ravi;Vaishnavi, Varadharajan;Kaliyanasundaram, Muthukrishnan;MaryHelen, Kilyara George;Sukanya, Ganesan;Munirajan, Arasambattu Kannan
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.8
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    • pp.3971-3977
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    • 2016
  • Background: Breast cancer, the commonest cancer among women in the world, ranks top in India with an incidence rate of 1,45,000 new cases and mortality rate of 70,000 women every year. Chemotherapy outcome for breast cancer is hampered due to poor response and irreversible dose-dependent cardiotoxicity which is determined by genetic variations in drug metabolizing enzymes and transporters. Pregnane X receptor (PXR), a member of the nuclear receptor superfamily, induces expression of drug metabolizing enzymes (DMEs) and transporters leading to regulation of xenobiotic metabolism. Materials and Methods: A genomic region spanning PXR 3' UTR was amplified and sequenced using genomic DNA isolated from 96 South Indian breast cancer patients. Genetic variants observed in our study subjects were queried in miRSNP to establish SNPs that alter miRNA binding sites in PXR 3' UTR. In addition, enrichment analysis was carried out to understand the network of miRNAs and PXR in drug metabolism using DIANA miRpath and miRwalk pathway prediction tools. Results: In this study, we identified SNPs rs3732359, rs3732360, rs1054190, rs1054191 and rs6438550 in the PXR 3; UTR region. The SNPs rs3732360, rs1054190 and rs1054191 were located in the binding site of miR-500a-3p, miR-532-3p and miR-374a-3p resulting in the altered PXR level due to the deregulation of post-transcriptional control and this leads to poor treatment response and toxicity. Conclusions: Genetic variants identified in PXR 3' UTR and their effects on PXR levels through post-transcriptional regulation provide a genetic basis for interindividual variability in treatment response and toxicity associated with chemotherapy.

Effect of Paraffin Oil on Prolongation of Green Period in Zoysiagrass (파라핀오일 처리가 한국잔디의 녹색기간 연장에 미치는 영향)

  • Lee, Dong-Woon;Lee, Suk-Jun;Lee, Chae-Min;Choi, Tae-Hyuk;Lee, Sang-Hoon;Choi, Dae-Hong;Chang, Tae-Hyun
    • Asian Journal of Turfgrass Science
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    • v.26 no.1
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    • pp.35-43
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    • 2012
  • These studies were carried out to ascertain the effects of paraffin oil on prolongation of the green leaf color period in Zoysiagrass. Fifty-fold diluted 98% paraffin oil treatment obtained the lowest reduction rate of green color. In early October we sprayed 50-fold, 100-fold and 200-fold diluted 98% paraffin oil in a Zoysia japonica field in Hapcheon of Gyeongnam and Sangju of Gyeongbuk and in a Z. matrella field in Gumjung of Busan and Anseong of Gyeonggii. Leaf color maintained for 60 days after treatment in Zoysia japonica. Leaf color remained for 60 days after treatment in Anseong, Hapcheon and Sangju when treated in the mid-October. Chlorophyll content was higher in paraffin oil treatment areas than in control areas in early October. Weight reduction rate was lower in the paraffin oil treated than in untreated leaves of Zoysiagrass when sprayed in Gumjung and Anseong in early October and mid-October, respectively. The chlorophyll content in leaves of Z. japonica was increased by increasing the spray volume of paraffin oil in the same dose treated in Lexington, Kentucky, USA. Paraffin oil can be used to prolongate of Zoysiagrass leaf color.

Effects of Daidzein on Body Weight Gain, Serum IGF-I Level and Cellular Immune Function in Intact Male Piglets

  • Wang, Genlin;Zhang, Xiangying;Han, Zhaoyu;Liu, Zhaobin;Liu, Weirong
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.7
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    • pp.1066-1070
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    • 2002
  • 10 male piglets at 5-6 weeks old with similar body weight (BW) were randomly assigned into the experimental (EXP) and control (CON) groups. The animals in EXP received intro-muscular injection with daidzein (DA) at the dose of 0.5 mg DA per kg start BW on day 1. The same procedures were repeated once every 3 days for eight times. The animals in CON received the injection only with same volume of control peanut oil. The animals were weighted on day 14 and 28 and the blood samples were obtained at different stages of the treatment for determining IGF-I levels and blood parameters. At the end of the experiment, the thymus and spleen from all the animals were surgically taken out and weighted. The results showed that BW and average daily gain (ADG) were not significantly different between the groups in term of the whole period, but ADG between days 14-28 was higher in EXP than in CON (p<0.05). On days 18, 21 and 25, IGF-I levels in EXP group were 20.53% (p<0.05), 15.92% (p>0.05) and 23.46% (p<0.05), respectively, higher than those in CON. The weights of thymus and spleen, the ratios of their weights to BW and red blood count (RBC) did not significantly differ between the groups at all stages. White blood count (WBC) in EXP steadily increased from day 22, reached its apex on day 24, which was higher than in CON (p<0.05) and its own levels on day 20 and 22 (p<0.01 or p<0.05), and remained higher on the later time (p=0.058). The results of percentage of T-Lymphocytes also demonstrated similar trend to WBC, but TLymphocyte transformation rate (%) appeared no significant change between the groups. In conclusion, Daidzein could stimulate male piglet growth and elevate serum IGF-I levels at certain stages of the treatment. It could also increase WBC and T-Lymphocyte rates, but had no significant impacts on RBC and T-Lymphocyte transformation rate.

The Effects Of Calcified Nodule Formation On Co-Cultre Of Periodontal Ligament Cells And Gingival Fibroblasts (치주인대세포와 치은 섬유아세포의 혼합배양이 석회화 결정형성에 미치는 영향)

  • In, Young-Mi;Park, Joon-Bong;Lee, Man-Sup;Kwon, Youg-Hyuk
    • Journal of Periodontal and Implant Science
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    • v.26 no.1
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    • pp.89-102
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    • 1996
  • The goal of periodontal therapy is to regenerate the loss of periodontal attachment appratus. Current theories suggest the cells of the periodontium have the capacity, when appropriately triggered, to actively participate in restoring connective tissues, including mineralized tissues. This study was performed to define the hard tissue regeneration effect of periodontal ligament(PDL) cells in vitro and the effect of rate of the composition in gingival fibroblasts(GF) on the hard tissue regeneration capacity of PDL cells. For this study, Cell growth rate, alkaline phosphatase(Al.Pase) levels and the ability to produce mineralized nodules in co-culture of PDL cells and GF were examined. The results were as follows : 1. At 7 and 15 days, Cell growth of co-culture of PDL and GF(50 : 50) was greater than that of PDL cells or GF alone(P>0.05). 2. Measurements of ALPase levels indicated that PDL cells had significantly higher activity when compared with that of co-culture groups and GF only(p<0.05). And, ALPase activity in 10 days was higher than that of 7 days(P>0.05) 3. The tendency of formation of the mineralized nodule were observed dose-depend pattern of PDL cells. There was statistically significant difference among group 1(PDL 100%), 2(PDL 70% : GF 30%), and 3(PDL 50% : GF 50%)(P<0.01). But, there was no difference among group 3, 4(PDL 30% GF 70%), and 5(GF 100%). 4. Also, the number of nodule was greater in co-culture of PDL 70% and GF 30% than in culture of PDL 70%(P<0.05) From the above results, it is assumed that the co-culture of PDL cells and GF stimulates the cell growth, which is not that of PDL cells but GF. And, the activity of ALPase depends on the ratio of PDL cells, and ALPase may relate to the initial phase of nodule formation. Also, it is thought that the calcified nodule formation principally depends on PDL cells, is inhibited by GF, and affected by cell density.

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Radiation Therapy for Primary Eyelid Cancers in Tunisia

  • Belaid, A;Nasr, C;Benna, M;Cherif, A;Jmour, O;Bouguila, H;Benna, F
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3643-3646
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    • 2016
  • Management of eyelid cancers is based on surgery and/or radiotherapy (RT). The treatment objective is to control tumors with acceptable functional and esthetic outcomes. The aim of this study was to evaluate the results of radiation therapy in management of epithelial eyelid cancers, reviewing retrospectively the clinical records of patients treated in our institution from January 1989 to December 2013. We focused on clinical and histological features, treatment characteristics, tolerance and disease control. One hundred and eight patients (62 men and 46 women) were enrolled, with a mean age of 61 years [ranges 15-87]. The most frequent tumor location was the inner canthus (42.6%). Median tumor size was 21 mm [ranges 4-70]. Histological type was basal cell carcinoma in 88 cases (81.5%), squamous cell carcinoma in 16 (14.8%) and sebaceous carcinoma in 4 (3.7%). Radiation therapy was exclusive in 67 cases (62%) and post-operative for positive or close margins in the remaining cases. Kilovoltage external beam radiotherapy (KVRT) was used in 63 patients (58.3%) and low-dose-rate interstitial brachytherapy in 37 (34.3%). Eight (7.4%) were treated with cobalt or with a combination of KVRT-cobalt, KVRT-electron beams, KVRT-brachytherapy or cobalt-electron beams. The total delivered radiation doses were 70 Gy (2 Gy/fraction) in 62 patients (57.4%), 66 Gy (2 Gy/fraction) in 37 (34.3%) and 61.2 Gy (3.4Gy/fraction) in 9 (8.3%). After a median follow-up of 64 months, we noted 10 cases of local recurrences(9.2%): 7 after exclusive and 3 after post-operative RT. No local recurrence occurred in patients treated with brachytherapy. Actuarial 5-year local recurrence-free rate, disease-free survival and overall survival were respectively 90%, 90% and 97%. T-stage was found to be a significant factor for recurrence (p=0.047). All acute radiation-related reactions were scored grade I or II. Delayed effects were eye watering in 24 cases (22.2%), eye dryness in 19 (17.6%), unilateral cataract in 7 (6.4%) and ectropion in 4 (3.7%). Radiation therapy and especially brachytherapy is an efficient treatment of eyelid cancers, allowing eye conservation and functional preservation with good local control rates and acceptable toxicity.

Environmental and Genetic Aspects of Obesity in Broilers (육계의 비만현상에 관한 고찰)

  • 김재홍
    • Korean Journal of Poultry Science
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    • v.9 no.1
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    • pp.1-16
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    • 1982
  • Excessive fat deposition, particularly in the abdominal region, has become a problem in broiler production. When the caloric intake exceeds the body demands for energy, excess food is stored as fat in broilers. Researchers have shown that fat deposition varies with breed, strain, sex age, nutrition, exercise, ambient temperature and rearing systems. These factors affect fat deposition through their effects on the size or the number of adipose cells or a combination of both. In some measurements on live birds to predict body fat, the wet weight and percentage fat of skin in pectoral feather tract are significantly correlated with percentage abdominal fat. But these correlation coefficients are not so high. Therefore, correlation coefficients indicate that these measurements on live birds ate not useful for estimating body fat weight and percentage. Most reports show that an increase in the proportion of carcass fat, when measured at a given age, is correlated with selection for increased body weight. On the other hand some research results show that selection for body$.$weight gain dose not lead to an alteration in the proportion carcass fat when measured at a given body weight. Besides, selection for improved food conversion efficiency alone resulted in a decrease in carcass fat and an increase in protein and water when measured at either a given age or body weight, Thus eventhough it is uncertain whether carcass fat is increasing as a result of body-weight selection in broilers: however it is clear that selection for improved food conversion efficiency, either alone or in combination with growth rate, should result in leaner carcasses than selection for growth rate alone.

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Gastrointestinal and Hepatic First-pass Effects of Triflusal in Rats (흰쥐에서 트리플루살의 위장관 및 간 초회통과효과)

  • Cho, Hea-Young;Jeong, Tae-Jin;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.31 no.4
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    • pp.265-271
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    • 2001
  • In order to elucidate the influence of intestinal and hepatic first-pass effect on the pharmacokinetics of triflusal, the biotransformation of triflusal in the gastrointestinal tract and liver was designed. Moreover, we tried to establish an HPLC method applicable for bioassay and available to pharmacokinetics, not only with the simultaneous determination of triflusal and its active metabolite, 2-hydroxy-4-trifluoromethyl benzoic acid (HTB), but also with improving sensitivity. After the administration of triflusal (10 mg/kg) and HTB (10 mg/kg) into femoral vein, portal vein (only triflusal) and oral route (only triflusal), pharmacokinetic parameters were investigated from the plasma concentration-time profiles of triflusal and HTB in rats. An HPLC method was developed for the simultaneous determination of triflusal and HTB in rat plasma, urine and bile. The HPLC analysis was carried out using a C18 column and acetonitrile-methanol-water (25:10:65, v/v/v) as the mobile phase and UV detection at 234 nm. Furosemide was used as the internal standard. The calibration curves were linear over the concentration range $0.05-5.0\;{\mu}g/ml$ for triflusal and $0.2-200.0\;{\mu}g/ml$ for HTB with correlation coefficients greater than 0.999 and with intra-day or inter-day coefficients of variation not exceeding 10.0%. This assay procedure was applied to the study of metabolite pharmacokinetics of triflusal and HTB in rats. It was supposed that triflusal was almost metabolized in vivo because urinary and biliary excreted amounts of triflusal could be ignored as it was lower than 1.2% of the administered dose. According to the gastrointestinal and hepatic biotransformation pathways of triflusal, it was found that triflusal was hydrolyzed by about 5% in intestine and metabolized by about 53% in liver, and that the bioavailability of triflusal after oral administration of triflusal was 0.44, and also that the fraction of total elimination rate of triflusal which formed HTB in liver $(F_{mi},\;%)$ was about 98%. These results showed that triflusal was almost metabolized in liver, and the total elimination of triflusal in the body was dependent to the formation rate of HTB from triflusal in liver.

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Antioxidant effect of ethanol extract from Poria cocos depending on cultivation methods (재배방법을 달리한 복령 에탄올추출물의 항산화 효과)

  • Kim, Yoo-Jin;Park, Hae-Jin;Lee, Jin Sang;Do, Eunju;Sohn, Hyeong Rack;Jeon, Seon Man;Yeum, Jeong Hyun;Kim, Mi Ryeo
    • The Korea Journal of Herbology
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    • v.31 no.5
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    • pp.107-114
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    • 2016
  • Objectives : Poria cocos Wolf has been widely used in Korean medicine as a medicinal fungus. In this study, we investigated that comparative anti-oxidant effects of ethanol extract from wild Poria cocos (WP) and plastic bag-cultivated Poria cocos (PBP).Methods : Total polyphenol and flavonoid contents in WP and PBP extract were monitored. And DPPH, ABTS, hydroxyl (·OH) free radical scavenging capacity, reducing power and xanthine oxidase inhibition activities of them were determined at 5, 1, 0.5 mg/ml concentrations.Results : Higher total polyphenol contents were found in the PBP extract (52.07±0.6 mg/TAEg) than in the WP extract (28.44±0.26 mg/TAEg). The flavonoid contents in WP and PBP extract were 17.29±0.30 mg/ RUEg, 21.36±0.40 mg/ RUEg, respectively. Also, DPPH, ABTS and ·OH free radical scavenging capacity of PBP extract in treated concentrations (5, 1, 0.5 mg/ml) significantly increased compared to those of WP-treated group. In particular, DPPH, ABTS free radical scavenging capacity and reducing power of PBP extract at 5 mg/ml concentration were similar to positive control (BHA or vit. C). Xanthine oxidase (XO) inhibition rate in both extract increased dose dependently. But it was significantly increased in PBP-treated group, only at 5 mg/ml, compared to those of WP-treated group. Then, their inhibition rate by PBP was similar to positive control (BHA).Conclusions : These results suggest that PBP extract is superior to WP extract in anti-oxidant capacity thus PBP can be applied in variable antioxidative products as a substitute for WP.