• Title/Summary/Keyword: TPA

Search Result 516, Processing Time 0.031 seconds

Effects of TPA and IAA on Corn Coleoptile Elongation (옥수수 자엽초의 신장에 미치는 TPA와 IAA의 효과)

  • 정은수
    • Journal of Plant Biology
    • /
    • v.35 no.1
    • /
    • pp.77-84
    • /
    • 1992
  • In view of the well-established role of protein kinase C effector element in signal transduction of animal systems, the possibility of diacylglycerol (DAG) and its analog 12-O-tetradecanoylphorbol13-acetate (TPA) having an effect on auxin-induced growih of com coleoptiles was explored. Both DAG and TP A were found to promote cell elongation in the coleoptile tissue_ Treatment of tissue with these protein kinase C-activating agents resulted in increase in the growth rate over the control by about 300%. When 1M was applied to TPA-pretreated coleoptiles. auxin effect appeared synergistic. Morever. coleoptile growth was found to be inhibited by staurosporine and methylated TPA, both of which are known to specifically inhibit protein kinase C. Electrophoretic and autoradiographic patterns of soluble proteins from the coeoptiles indicated that either 1M or TPA tereatment resulted in increased phosphorylation of certain proteins of 205 Kd. 66 Kd and 32 Kd in size. The results obtained from the present work suggest that protein kinase C may be associated with auxin action on cell elongation in the corn coleoptile segments.gments.

  • PDF

Near-IR Spectroscopic Studies of the Hydrogen Bonding Between Thiopropionamide and N,N-Dimethylalkylamide in Carbon Tetrachloride (사염화탄소 중에서 Thiopropionamide와 N,N-Dimethylalkylamide사이의 수소결합에 관한 분광학적 연구)

  • Byung-Chul Kim;Chang-Ju Yoon;Kyuseok Song;Young Sang Choi
    • Journal of the Korean Chemical Society
    • /
    • v.33 no.2
    • /
    • pp.156-163
    • /
    • 1989
  • The $ν_a+amide II$ combination band of thiopropionamide has been recorded for investigation of Hydrogen bonding between thiopropionamide (TPA) and N,N-dimethylalkylamide (DMF, DMA and DMP) in carbon tetrachloride over the range of $5^{\circ}$ to $55^{\circ}$. The combination band of monomeric TPA and hydrogen-bonded TPA can be resolved by Lorentzian-Gaussian product function into monomeric TPA and hydrogen-bonded TPA with amides. The association constants ($K_1$) for the hydrogen-bonded TPA were calculated by the concentrations of the monomeric TPA and the hydrogen-bonded TPA obtained from the computer resolved absorption bands. Thermodynamic parameters for the Hydrogen bonding have been evaluated by the analysis of the temperature dependent spectra. The ${\Delta}$$H^{\circ}$ of hydrogen-bonded TPA with DMF, DMA and DMP have been found to be-12.5, -13.5 and -14.1 kJ/mol, respectively. The corresponding ${\Delta}$$S^{\circ}$for the above system were -15.2, -17.9 and -22.3 J/mol${\cdot}$deg, respectively.

  • PDF

Insights from edTPA in the United States on assessing professional competencies of preservice mathematics teachers (미국 edTPA 평가에서 요구하는 예비 수학 교사의 전문적 역량 분석)

  • Kwon, Oh Nam;Kwon, Minsung;Lim, Brian S.;Mun, Jin;Jung, Won;Cho, Hangyun;Lee, Kyungwon
    • The Mathematical Education
    • /
    • v.62 no.2
    • /
    • pp.211-236
    • /
    • 2023
  • The purpose of this study is to derive implications of preservice mathematics teacher education in Korea by analyzing the case of edTPA used in the preservice teacher training process in the United States. Recently, there has been a growing interest in promoting professional competencies considering not only the cognitive dimension related to knowledge development of preservice mathematics teachers but also the situational dimension considering reality in the classroom. The edTPA in the United States is a performance-based assessment based on lessons conducted by preservice teachers at school. This study analyzes the professional competencies required of preservice mathematics teachers by analyzing handbooks that described the case of edTPA in which preservice mathematics teachers in the United States participate. The edTPA includes planning, instruction, and assessment tasks, and continuous tasks are performed in connection with classes. Thus, the analysis is conducted on the points of linkage between the description of evaluation items and criteria in the planning, instruction, and assessment tasks, as well as the professional competencies required from that linkage. As a result of analyzing the edTPA handbooks, the professional competencies required of preservice mathematics teachers in the edTPA assessment were the competency to focus on and implement specific mathematics lessons, the competency to reflectively understand the implementation and assessment of specific mathematics lessons, and the competency to make a progressive determination of students' achievement related to their learning and their uses of language and representations. The results of this analysis can be used as constructs for competencies that can be assessed in the preservice in the organization of the preservice mathematics teacher curriculum and practice training semester system in Korea.

Effect of Compression Test Conditions on Texture Profile Analysis of Surimi-based Products (압착실험조건이 어육연제품의 조직감 면모분석에 미치는 영향)

  • Lee, Young-Seung;Yoo, Byoung-Seung
    • Korean Journal of Food Science and Technology
    • /
    • v.32 no.1
    • /
    • pp.225-230
    • /
    • 2000
  • The texture profile analysis (TPA) parameters of commercial surimi-based products were evaluated at various compression test conditions. Cylindrical specimens of diameter to length (D/L) ratio of 1.0, 1.5, B.() cm/min were compressed to 50, 65 and 80% using crosshead speeds of 1.7, 3.3, 6.7 cm/min. TPA parameters of three surimi-based products (hardness-1, hardness-2, cohesiveness, springiness, chewiness and gumminess) were analyzed statistically. The TPA parameters were modified by dividing with cross section area and strain. The TPA parameters were affected by D/L and compression ratio except for crosshead speed for all three surimi-based products. The ecommended test conditions for TPA of surimi-based products seem to be D/L of 1.5, compression ratio of 80%, and crosshead speed of 1.7 to 6.7 cm/min.

  • PDF

Induction of Mouse Epidermal ODC by TPA and Inhibition by Plant Flavonoids, in Skin Tumor Promotion (다단계 발암과정 중 Promotion 단계에서의 TPA에 의한 Mouse Epidermal ODC의 유도 및 약물에 의한 차단효과)

  • 김미경;장일식;정문호
    • Journal of Environmental Health Sciences
    • /
    • v.19 no.3
    • /
    • pp.64-73
    • /
    • 1993
  • The study was conducted to investigate the mechanism of tumor promotion as the time courses and the doses of promoter, and the effect of plant fiavonoids on the TPA-induced ODC responses. The results are summarized as follows: 1. A single, toppical application of 17 nmole of the potent tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate, resulted in an induction of mouse epidermal Ornithine Decarboxylase with a peak at 5 hours after treatment and maximized 5.1 times as large as ODC activities of control. 2. Dose-response curve indicated that the tumor promotion increases proportionally between 1.7 and 170 nmole of TPA. This dose dependency relationship indicated that the ability of TPA to stimulate ODC is linked its ability to promote tumors. 3. Naturally occurring plant fiavonoids with anticarcinogenic and antipromotional activities were tested for their abilities to inhibit ODC response induced by skin tumor promoter TPA. Intra peritoneal administration of fiavonoids compounds (rutin, naphthofiavone, baicalein, quercitrin) and herbal drugs (sophorae rios, crataegi fructus, armeniacae semen) inhibited 17 nmole TPA-induced ODC activities in mouse epidermis in vivo.

  • PDF

The Inhibitory Effect of Chlorophyllin is Influenced by Different Promotion Stages in DMBA-TPA-induced Mouse Skin Carcinogenesis

  • Kim, Jin;Yook, Jong-In;Park, Kwang-Kyun;Lee, Eun-Ha;Jung, So-Young;Joon, Yin-Liu;Kyung, Chul-Hong;Kim, Ju;Chung, Won-Yoon
    • Environmental Mutagens and Carcinogens
    • /
    • v.19 no.1
    • /
    • pp.46-55
    • /
    • 1999
  • To develop a chemopreventive strategy based on the different stages of premalignant lesions, we hypothesized that the inhibitory effect of chemopreventive agents is influenced by different promotion stages during carcinogenesis. DMBA-TPA-induced skin carcinogenesis was used with ICR mice and chlorophyllin (CHL) was applied as a chemopreventive agent. In vitro assay was performed with Salmonella typhi. TA100 to observe any anti-mutagenic activity of CHL against DMBA. Pre-initiation and pre-promotion effects of CHL were observed by CHL treatment before initiation and before promotion. To evaluate the inhibitory effect at different promotion stages, each group was divided into three subgroups after TPA promotion for 6, 18 and 24 weeks, respectively ; the first subgroup was immediately sacrificed after termination of TPA, the second subgroup was treated with CHL, and the third subgroup was sacrificed 8 weeks after termination of TPA without CHL treatment. The degrees of epithelial dysplasia, papilloma formation, and invasive carcinoma were observed histologically, and GST-Pi expression was observed immunohistochemically. ODC mRNA level was analyzed by reverse transcriptase-polymerase chain reaction. Results showed : CHL dose-dependently inhibited the mutation of Salmonella typhi. TA100; the incidence of epithelial dysplasia and papilloma formation was lower in pre-initiation and pre-promotion CHL-treated mice than DMBA-TPA-treated mice; no invasive carcinoma developed in pre-initiation CHL-treated groups, while 67% of DMBA-TPA treated mice had carcinomas; GST-Pi expression decreased when CHL was treated before initiation and before promotion; and when CHL was treated after termination of TPA application at 18 and 24- week-TPA promotion stages, respectively, the incidence of epithelial dysplasia and papilloma was markedly reduced compared to non-treated groups. When comparing the incidence of epithelial dysplasia and papilloma between the immediately-sacrificed subgroup and the non-treated group with a waiting period, we speculated that the 18-week-TPA promotion stage might belong to the promoter-independent progression stage. At the 18-week-TPA promotion stage, the level of ODC mRNA in the CHL-treated group was clearly reduced to the level of normal tissue. Taking these results together, CHL showed both anti-initiation and anti-promotion effects, while the inhibitory effect of CHL was prominent in the 18-week-TPA promotion stage. However, CHL seems to be incapable of completely blocking the progression in the 24-week-TPA promotion stage.

Structural Changes on the HL-60 Cells of TPA-induced Adherence by Asadisulphide

  • Ahn, Byung-Zun;Kim, Seon-Hee;Park, Mi-A;You, Kwan-Hee
    • Biomedical Science Letters
    • /
    • v.8 no.1
    • /
    • pp.13-20
    • /
    • 2002
  • Asadisulphide were purified from Ferrula assafoetida by organic solvent extraction and chromatography. Since ethyl acetate extracts of F. assafoetida has the strongest inhibitory effects on adherence of HL-60 cells, it was reextracted with ethyl acetate, hexane, and ethyl ether and chromatographed three times to isolate asadisulphide. HL-60 cells were grouped into untreated control, TPA-treated, asadisulphide-teated and TPA+asadisulphide-treated groups, and structural changes of these cells were observed using light microscope, scanning electron microscope and transmission electron microscope to examine the inhibitory effects of asadisulfide on the TPA-induced adherence of HL-60 cells. Light microscopic observations showed that asadisulphide has inhibitory effects on the cell aggregation, extention of cytoplasmic processes and inhibition of substrate adhesion of HL-60 cells. Using scanning and transmission electron microscope, it was observed that cell surfaces and several ultrastructures of TPA-treated HL-60 cell were different from control group, while there were no remarkable differences between asadisulphide-treated and TPA+asadisulphide-treated group. These results could suggest that asadisulphide has the inhibitory effects on the TPA-induced structural changes of HL-60 cells.

  • PDF

Dissolution Enhancements of Tiaprofenic Acid by ${\beta}-Cyclodextrin$ Complexation (${\beta}-Cyclodextrin$과의 복합체 형성에 의한 Tiaprofenic Acid의 용출증가)

  • Chun, In-Koo;Park, In-Sook
    • Journal of Pharmaceutical Investigation
    • /
    • v.16 no.2
    • /
    • pp.55-67
    • /
    • 1986
  • Inclusion complexation of tiaprofenic acid (TPA) with cyclodextrins $({\alpha}-,\;{\beta}-,\;{\gamma}-CyDs)$ in aqueous solution and in solid phase was investigated by solubility method, measurement of partition coefficient, ultra-violet, circular dichroism, infrared spectroscopies, powder X-ray diffractometry and differential scanning calorimetry. Investigations were made to prepare inclusion complexes of TPA with ${\beta}-CyD$ in solid powdered form by coprecipitation, freeze-drying, spray-drying and co-pulverization methods. The coprecipitation, freeze-drying and spray-drying methods were successful in obtaining inclusion complexes. The results showed that the latter two methods might be originally superior to the former in obtaining powdered inclusion completes. Especially, it was shown by powder X-ray diffractometry that spray-dried ${\beta}-CyD$ alone, TPA-spray-dried ${\beta}-CyD$ physical mixture, and spray-dried $TPA-{\beta}-CyD$ complex were amorphous. The dissolution behaviours of $TPA-{\beta}-CyD$ systems prepared by above four methods were compared with those of TPA alone and $TPA-{\beta}-CyD$ physical mixture, and the rates of dissolution of TPA in pH 1.2 buffer were greatly enhanced by inclusion complexation and copulverization.

  • PDF

Induction of Oocyte Ovulation and Prostaglandin Synthesis by Gonadotropin and Phorbol Ester in vitro in Amphibian (Rana n igromacu la ta) Ovarian Follicles (뇌하수체 호르몬과 포르볼에스터에 의한 참개구리 난자의 배란과 프로스타글라딘 합성유도)

  • 장경자;나철호;소재목;이원교;권혁방
    • The Korean Journal of Zoology
    • /
    • v.39 no.3
    • /
    • pp.266-272
    • /
    • 1996
  • Experiments were carried out to ascertain whether gonadotropin or a phorbol ester (12-O-tetradecanoyl phorbol-13-acetate, TPA) induces oocyte ovulation and stimulates prostaglandin synthesis by Rana ovarian follicles in vitro. Rana nigromaculata collected from underground in spring were utilized for the present experiment. Treatment of frog pituitary homogenate (FPH) or TPA to ovarian fragments in culture induced oocyte ovulation in a dose dependent manner and stimulated prostaglandin F2a (PGF$_2$$\alpha$ synthesis. Both treatruents were more effective in inducing the ovulation and PGF$_2$$\alpha$ secretion by the follicles obtained in May than those in April. A Protein kinase C inactivator, 1-(5-isoquinolinyl-sulfonyl)-2-methyl-piperazine (H-7), or cyclooxygenase inhibitor, indomethacin (IM) suppressed the FPH- or TPA-induced PGF$_2$$\alpha$ production, but IM failed to suppress the FPH- or TPA-induced ovulation. Time course of oocyte ovulation and PGF$_2$$\alpha$ secretion by FPH and TPA treatments were very similar to each other. FPH stimulated progesterone secretion by the follicle but TPA failed to do so. Taken together, the data presented here suggest that protein kinase C (PKC) in follicle play a role in the ovulation process of Rana nigromaculata, probably via prostaglandin synthesis.

  • PDF

A Study on Performance Improvement of Glucose Sensor Adopting a Catalyst Using New Cross Liker (새로운 가교제를 적용한 촉매를 이용한 글루코스 센서의 성능향상 연구)

  • Chung, Yongjin;Kwon, Yongchai
    • Korean Chemical Engineering Research
    • /
    • v.53 no.6
    • /
    • pp.802-807
    • /
    • 2015
  • In this study, we synthesized a new biocatalyst consisting of glucose oxidase (GOx), polyethyleneimine (PEI) and carbon nanotube (CNT) with addition of terephthalaldehyde (TPA) (TPA/GOx/PEI/CNT) for fabrication of glucose sensor that shows improved sensing ability and stability compared with that using other biocatalysts. Main bonding of the new TPA/GOx/PEI/CNT catalyst is formed by Aldol condensation reaction of functional end groups between GOx/PEI and TPA. Such formed bonding structure promotes oxidation reaction of glucose. Catalytic activity of TPA/GOx/PEI/CNT is evaluated quantitatively by electrochemical measurements. As a result of that, large sensitivity value of $41{\mu}Acm^{-2}mM^{-1}$ is gained. Regarding biosensor stability of TPA/GOx/PEI/CNT catalyst, covalent bonding formed between GOx/PEI and TPA prevents GOx molecules from becoming leaching-out and contributes improvement in biosensor stability. With estimation of the biosensor stability, it is found that the TPA/GOx/PEI/CNT catalyst keeps 94.6% of its initial activity even after three weeks.