• Title/Summary/Keyword: salt sensitivity

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Characterization of two plasma membrane protein 3 genes (PutPMP3) from the alkali grass, Puccinellia tenuiflora, and functional comparison of the rice homologues, OsLti6a/b from rice

  • Chang-Qing, Zhang;Shunsaku, Nishiuchi;Shenkui, Liu;Tetsuo, Takano
    • BMB Reports
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    • v.41 no.6
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    • pp.448-454
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    • 2008
  • Two full-length cDNAs, PutPMP3-1 and PutPMP3-2, encoding PMP3 family proteins were isolated from Puccinellia tenuiflora, a monocotyledonous halophyte. Expression of both genes was induced by low temperature, salt stress, dehydration, ABA, and $NaHCO_3$. Transcripts of PutPMP3-2 were more strongly induced by these stresses relative to those of PutPMP3-1, particularly under low temperature and dehydration conditions. Expression of PutPMP3-1 and PutPMP3-2 in yeast mutants lacking the PMP3 gene can functionally complement the membrane hyper-polarization and salt sensitivity phenotypes resulting from PMP3 deletion. To compare the functions of PutPMP3-1 and PutPMP3-2, the orthologous genes in rice (OsLti6a and OsLti6b) were isolated. Both OsLti6a and OsLti6b could functionally complement the loss of PMP3 in yeast. PutPMP3-2 and OsLti6a were more effective in reversing membrane hyperpolarization than PutPMP3-1 and OsLti6b. However, the four yeast transformants each showed similar levels of salt tolerance. These results imply that these PMP3 family members don't function identically under different stress tolerance conditions.

Ecotoxicity Evaluation of PFCs using Marine Invertebrate, Sea Urchin (Mesocentrotus nudus) (둥근성게(Mesocentrotus nudus)를 이용한 과불화화합물의 생태독성평가)

  • Choi, Hoon;Lee, Ju-Wook;Lee, Seung-Min;Jeon, Hyung-Ju;Heo, Seung;Hwang, Un-Ki
    • Journal of Marine Life Science
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    • v.6 no.2
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    • pp.80-87
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    • 2021
  • In this study, the toxic effects of PFOA and PFOS potassium salt on Mesocentrotus nudus using 10 min-fertilization rate and 48 h-normal embryogenesis were confirmed through the calculation of toxicity values such as Non-observed effective concentration, Low-observed effective concentration, and 50% of effective concentration. The case of 10 min-fertilization rate and 48 h-normal embryogenesis showed the concentration-dependent reduction pattern when exposed to PFOA and PFOS potassium salt, in tested concentration, respectively. The EC50 values of 10 min-fertilization rates for PFOA and PFOS potassium salt were 1346.43 mg/l and 536.18 mg/l, respectively, and the EC50 values of 48 h-normal embryogenesis were 42.67 mg/l and 17.81 mg/l, respectively. Both toxicity test methods showed high toxicity sensitivity to PFOS potassium salt. Recent studies have shown that the concentration of PFOA and PFOS in the marine environment has continuously decreased, and it is not enough to show acute toxicity to sea urchin. However, PFOA and PFOS have a very long half-life and can accumulate throughout the life of marine life, so it is still observed at a high concentration in shellfish. Therefore, a study on chronic toxicity through the whole-life cycle of marine organisms in coastal environments should be needed.

Development of Inductive and Capacitive Type Intraocular Pressure (IOP) Sensor to Improve Sensitivity and Minimize Size (민감도 향상과 센서 소형화를 위한 자기 및 용량형 안압센서의 개발)

  • Jang, Cheol In;Shin, Kyeong-Sik;Yun, Kwang-Seok;Kim, Yong Woo;Kang, Ji Yoon;Lee, Soo Hyun
    • Journal of Sensor Science and Technology
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    • v.23 no.6
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    • pp.409-415
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    • 2014
  • We had presented an inductive type intraocular pressure sensor (L-sensor) in previous work. The distance between a micro coil and a ferrite on the membrane was modulated by pressure, and as a result the inductance and resonant frequency were changed. However, L-sensor has some problems to implant in eyes. First problem is low sensitivity. When L-sensor was implanted in rabbit's eyes, resonant frequency of L-sensor was very hard to detect. Second problem is biocompatibility. Size of L-sensor is $6{\times}7{\times}1.2mm$. When L-sensor was implanted in the eyes, it caused the inflammation. Therefore, this study suggests an inductive and capacitive type IOP sensor (LCsensor). The sensitivity of the LC-sensor 27.3 kHz/mmHg under 60mmHg. It is much larger than 14 kHz/mmHg of the L-sensor. And the size of LC-sensor is 47% smaller than L-sensor. After 2 weeks from the implantation of LC-sensor into rabbit eyes, we measured the changes of resonant frequency of LC-sensor according to increased IOP by Balanced Salt Solution (BSS) injection. As a result, the sensitivity of LC-sensor in in vivo test is 25 kHz/mmHg. That is similar to the sensitivity of in vitro test.

Prediction of Chemotherapeutic Response in Unresectable Non-small-cell Lung Cancer (NSCLC) Patients by 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) Assay

  • Chen, Juan;Cheng, Guo-Hua;Chen, Li-Pai;Pang, Ting-Yuan;Wang, Xiao-Le
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.3057-3062
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    • 2013
  • Background: Selecting chemotherapy regimens guided by chemosensitivity tests can provide individualized therapies for cancer patients. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium, inner salt (MTS) assay is one in vitro assay which has become widely used to evaluate the sensitivity to anticancer agents. The aim of this study was to evaluate the clinical applicability and accuracy of MTS assay for predicting chemotherapeutic response in unresectable NSCLC patients. Methods: Cancer cells were isolated from malignant pleural effusions of patients by density gradient centrifugation, and their sensitivity to eight chemotherapeutic agents was examined by MTS assay and compared with clinical response. Results: A total of 37 patients participated in this study, and MTS assay produced results successfully in 34 patients (91.9%). The sensitivity rates ranged from 8.8% to 88.2%. Twenty-four of 34 patients who received chemotherapy were evaluated for in vitro-in vivo response analysis. The correlation between in vitro chemosensitivity result and in vivo response was highly significant (P=0.003), and the total predictive accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for MTS assay were 87.5%, 94.1%, 71.4%, 88.9%, and 83.3%, respectively. The in vitro sensitivity for CDDP also showed a significant correlation with in vivo response (P=0.018, r=0.522). Conclusion: MTS assay is a preferable in vitro chemosensitivity assay that could be use to predict the response to chemotherapy and select the appropriate chemotherapy regimens for unresectable NSCLC patients, which could greatly improve therapeutic efficacy and reduce unnecessary adverse effects.

Putative fructose-1,6-bisphosphate aldolase 1 (AtFBA1) affects stress tolerance in yeast and Arabidopsis

  • Moon, Seok-Jun;Shin, Dong-Jin;Kim, Beom-Gi;Byun, Myung-Ok
    • Journal of Plant Biotechnology
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    • v.39 no.2
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    • pp.106-113
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    • 2012
  • Glycolysis is responsible for the conversion of glucose into pyruvate and for supplying reducing power and several metabolites. Fructose-1,6-bisphosphate aldolase (AtFBA1), a central enzyme in the glycolysis pathway, was isolated by functional complementation of the salt-sensitive phenotype of a calcineurin (CaN)-deficient yeast mutant. Under high salinity conditions, aldolase activity and the concentration of NADH were compromised. However, expression of AtFBA1 maintained aldolase activity and the NADH level in yeast cells. AtFBA1 shares a high degree of sequence identity with known class I type aldolases, and its expression was negatively regulated by stress conditions including NaCl. The fusion protein GFP-AtFBA1 was localized in the cytosol of Arabidopsis protoplasts. The seed germination and root elongation of AtFBA1 knock-out plants exhibited sensitivity to ABA and salt stress. These results indicate that AtFBA1 expression and aldolase activity is important for stress tolerance in yeast and plants.

Expression of Bacillus subtilis proBA Genes and Reduction of Feedback Inhibition of Proline Synthesis Increases Proline Production and Confers Osmotolerance in Transgenic Arabidopsis

  • Chen, Mingqing;Wei, Hongbo;Cao, JunWei;Liu, Ruijie;Wang, Youliang;Zheng, Congyi
    • BMB Reports
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    • v.40 no.3
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    • pp.396-403
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    • 2007
  • Proline accumulation has been shown to correlate with tolerance to drought and salt stresses in plants. We attempt to introduce the wild-type, mutant, and fusion proBA genes derived from Bacillus subtilis into Arabidopsis thaliana under the control of a strong promoter cauliflower mosaic virus 35S (CaMV35S). The transgenic plants produced higher level of free proline than control and the overproduction of proline resulted in the increased tolerance to osmotic stress in transgenic plants. Besides, the mutation in proBA genes, which were proved to lead $\alpha$-glutamyl kinase ($\alpha$-GK) reduces sensitivity to the end-product inhibition and the fusion of proB and proA also result in increasing proline production and confer osmotolerance in transgenic lines.

Pulse-echo response of ultrasonic transducer fabricated with PZT-polymer 3-3 type composite (PZT-고분자 3-3형 복합압전체 소자로 제작된 초음파 트랜스듀서의 펄스에코 응답특성)

  • 박정학;최헌일;손무현;사공건
    • Electrical & Electronic Materials
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    • v.9 no.10
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    • pp.1053-1059
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    • 1996
  • The pulse-echo response of the piezoceramics PZT-polymer 3-3 type composite transducers with various PVA additions were investigated. The PZT powder was prepared by the molten salt synthesis method. The porous PZT specimens will be used as a filler to make 3-3 type comosite were prepared from a mixture of PZT and polyvinylalcohol(PVA) sphere by utilizing BURPS(Bumout Plastic Sphere) technique. It was shown that the transmitting and receiving sensitivity of 3-3 type piezoelectric composite transducers could be improved than that of solid PZT transducers. The reason is that 3-3 type piezoelectric composite have low dielectric constant, density and acoustic impedance. The distance between transducer and reflector was in good agreement with the distance calculated from the longitudinal velocity of the specimens and receiving time observed pulse-echo responses on the ultrasonic transducer analyzer.

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Influence of Notch Change on Corrosion Fatigue Fracture in F.E.M. Dual phase Steel of SS41 Steel (SS41강의 F.E.M.복합조직강에서 노치변화가 부식피로파괴에 미치는 영향)

  • 도영민;이규천
    • Journal of the Korean Society of Safety
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    • v.16 no.2
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    • pp.44-50
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    • 2001
  • The rotated bending fatigue test was conducted in air md in 3.5% NaCl salt solution to investigate the fatigue fracture behaviour of raw material and F.E.M dual phase steel made from raw material(SS41) by a suitable heat treatment. This study has compared the initial microcrack creation of material by tensile test with that by fatigue test. And the rotated bending test of cantilever type under the condition of 3.5% NaCl salt solution and air has investigated the corrosion fatigue fracture behaviour with the variation of stress concentration factor determined by each of notch shapes. The initial microcrack have been developed in fragile grainboundary with general corrosion occurring in raw material : in the pits built up by corrosion in F.E.M. dual phase steel because pits bring out stress concentration. It is small that the degree of decrease in corrosion fatigue life for F.E.M. dual phase steel compared with raw material because the notch sensitivity of F.E.M. dual phase steel is lower than raw material in reason of characteristics with two-phase construction.

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Piezoelectric properties of porous PZT ceramics for hydrophone Applications (수중청음기 응용을 위한 다공질 PZT 세라믹스의 압전특성)

  • 박정학;이수호;공사건;배진호
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.4
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    • pp.558-561
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    • 1996
  • PZT powders were prepared by the molten salt synthesis method. The porous PZT ceramics were made from a mixture of PZT and polyvinylalcohol(PVA) by BURPS(Burnout Plastic Sphere) technique. The porous PZT bodies were fabricated from the green compacts with various amounts of PVA spheres. The piezoelectric coefficient d$_{33}$ (334~350*10$^{-12}$ C/N)of porous PZT ceramics(364*10$^{-12}$ C/N). The figure of merit(d$_{h}$g$_{h}$) of porous PZT specimens evaluating the sensitivity for ultrasonic transducer applications was improved significantly(11~70times) in comparison with that of single phase PZT ceramics(100*10$^{-15}$ m$^{2}$/N). The thickness mode coupling factor k$_{t}$(0.5~0.6) of porous specimens was comparable with that of single phase PZT ceramics(k$_{t}$=0.7). The mechanical quality factor of porous PZT specimens was smaller than 10, and thus these porous PZT ceramics would be believed as a good candidate for broad band hydrophone applications. (author). 10 refs., 7 figs.igs.igs.

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Acute Toxicity of Pentachlorophenol Sodium Salt, Potassium Dichromate, Sodium Azide to Neocaridina denticulata (Pentachlorophenol Sodium Salt, Potassium Dichromate, Sodium Azide에 대한 새뱅이(Neocaridina denticulata) 급성독성)

  • Lee, Jae-Woo;Moon, Ye-Ryeon;Yoon, Jun-Heon;Choi, Kyung-Hee;Han, Jin-Seok;Ryu, Ji-Sung
    • Environmental Analysis Health and Toxicology
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    • v.25 no.3
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    • pp.223-228
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    • 2010
  • Neocaridina denticulata is a small freshwater shrimp indigenous to Korea. As an indigenous species has long-adapted to particular water environments, the species can be a suitable indicator to assess environmental risks caused by hazard chemicals in the particular site. Thus Neocaridina denticulata, a small freshwater shrimp indigenous to Korea, is worth considering for a test species for such purpose. N. denticulata were exposed to pentachlorophenol sodium salt, sodium azide and potassium dichromate using automatic flow-through system for 96 hours. The 96 hr lethal concentrations ($LC_{50}$) of these chemicals were calculated as $0.53{\pm}0.09\;mg/L$, $2.40{\pm}0.61\;mg/L$ and $1.21{\pm}0.09\;mg/L$ respectively and showed relatively small deviation from repetitive test results. When compared with the toxicity values of other species for each chemical, N. denticulata had moderate or high sensitivity to the toxicity of these chemicals. It can be concluded that N. denticulata is a good test species to evaluate acute toxicity of various hazardous chemicals.