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1

Yiu, Nai Sum. "Immunomodulatory effects of tryptanthrin on human bronchial epithelial cells." HKBU Institutional Repository, 2005. http://repository.hkbu.edu.hk/etd_ra/586.

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2

Chiu, I.-Fan, and 邱一帆. "I. The apoptotic activity of tryptanthrin derivatives in MCF7 cells II. Inhibition of TCDD-induced aryl hydrocarbon receptor translocation by tryptanthrin derivative DQ181." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/19816042560757980017.

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Abstract:
碩士
國立臺灣大學
藥學研究所
89
I. The apoptotic activity of tryptanthrin derivatives in MCF7 cells Tryptanthrin, indolo[2,1-b]quinazolin-6,12-dione, is a coplanar four-fused ring compound which contains N-phenyl-quinazoline skeleton similar to 2-phenyl-naphthalene. It was illustrated that compounds containing coplanar 2-phenyl-naphthalene skeleton exhibit different biological activites, while the bioactivities would be decreased or lost in unplanar structures. For example, batracylin, containing 2-phenyl-quinolone skeleton,inhibits the growth of carcinoma cell lines. In previous data, tryptanthrin derivatives with different substituents exert different potency of various bioactivities. It draws our attention to screen tryptanthrin derivatives for cytotoxicity and study their apoptotic activity as potential anticancer agents. In the cytotoxic assay, tryptanthrin derivatives, DQ181, DQ166 and EY093, exert cytotoxic activity in cancer cell lines including MCF7, HeLa, A498, SKOV3 cells. Our data showed that cells undergo apoptosis and die. MCF7 cells are the most sensitive to these tryptanthrin derivatives. DQ181 is the most potent compound of those tryptanthrin derivatives. The result suggested that DQ181 may be a new compound developed to treat breast cancer. We further study the mechanism of apoptosis induced by DQ181. The extensive experiments indicated DQ181-induced apoptosis may be via upregulation of the expression of Fas receptor and Fas ligand, resulting in activating caspase-8 mediated pathway. Fas receptor protein overexpresses in two hours but decrease later. Fas ligand protein expression stimulated by DQ181 was elevated in a time dependent manner。 II. Inhibition of TCDD-induced aryl hydrocarbon receptor translocation by tryptanthrin derivative DQ181 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds induce a broad spectrum of biochemical and toxic responses including carcinogenesis. Binding of TCDD to Ah receptor is followed by AhR transport to the nucleus, dimerization with the aryl hydrocarbon nuclear translocator (ARNT), and transcription of a potentially large number of genes containing AhR complex-binding sequences in their promoter regions. Genes encoding cytochrome P450s(CYPs) enzymes are regarded as AhR-regulated genes. Induction of cytochrome P1A1 mRNA is a sensitive marker of AhR—ligand interaction. Our result demonstrates that tryptanthrin derivative DQ181 can inhibit TCDD-induced cytochrome P1A1 mRNA expression regarding to blocking or stablizing AhR-Hsp90 complex followed by inhibition of translocation from cytosol to nuclear. It may interfere with cytochrome P450 1A1-related carcinogenesis.
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3

"Modulatory effects of tryptanthrin on the murine myeloid leukemia cells." 2008. http://library.cuhk.edu.hk/record=b5893599.

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Abstract:
Chan, Hoi Ling.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2008.
Includes bibliographical references (leaves 206-220).
Abstracts in English and Chinese.
ACKNOWLEDGEMENTS --- p.i
ABBREVIATIONS --- p.ii
ABSTRACT --- p.viii
撮要 --- p.xii
PUBLICATIONS --- p.xiv
TABLE OF CONTENTS --- p.xv
Chapter CHAPTER 1: --- GENERAL INTRODUCTION
Chapter 1.1 --- Hematopoiesis & Leukemia --- p.1
Chapter 1.1.1 --- An Overview on Hematopoiesis Development --- p.1
Chapter 1.1.2 --- Leukemia --- p.6
Chapter 1.1.2.1 --- General Symptoms of Leukemia --- p.7
Chapter 1.1.2.2 --- Classification of Leukemia --- p.8
Chapter 1.1.2.3 --- Conventional Treatment against Leukemia --- p.15
Chapter 1.1.2.4 --- Novel Approaches --- p.19
Chapter 1.2 --- The Chinese Medicinal Herb-Banlangen (板藍根) --- p.24
Chapter 1.2.1 --- An Overview on Natural Indigo Compounds Derived from Banlangen --- p.24
Chapter 1.2.2 --- Tryptanthrin --- p.29
Chapter 1.2.2.1 --- Anti-bacterial Activity of Tryptanthrin --- p.29
Chapter 1.2.2.2 --- Anti-tumor Activity of Tryptanthrin --- p.31
Chapter 1.2.2.3 --- Anti-inflammatory Activity of Tryptanthrin --- p.33
Chapter 1.2.2.4 --- Cutting Edges of Tryptanthrin as a Drug --- p.34
Chapter 1.2.2.5 --- Metabolism of Tryptanthrin --- p.35
Chapter 1.3 --- Aims and Scopes of This Investigation --- p.37
Chapter CHAPTER 2: --- MATERIALS AND METHODS
Chapter 2.1 --- Materials --- p.39
Chapter 2.1.1 --- Animals --- p.39
Chapter 2.1.2 --- Cell Lines --- p.39
Chapter 2.1.3 --- "Cell Culture Medium, Buffers and Other Reagents" --- p.41
Chapter 2.1.4 --- Reagents for 3H-Thymidine Incorporation Assay --- p.45
Chapter 2.1.5 --- Reagents and Buffers for Flow Cytometry --- p.46
Chapter 2.1.6 --- Reagents for DNA Extraction --- p.49
Chapter 2.1.7 --- Reagents for Measuring Caspase Activity --- p.50
Chapter 2.1.8 --- Reagents for Total RNA Isolation --- p.53
Chapter 2.1.9 --- Reagents and Buffers for Reversed Transcription-PCR --- p.54
Chapter 2.1.10 --- Reagents and Buffers for Real Time-PCR --- p.59
Chapter 2.1.11 --- Reagents and Buffers for Gel Electrophoresis of Nucleic Acids --- p.59
Chapter 2.1.12 --- "Reagents, Buffers and Materials for Western Blot Analysis" --- p.61
Chapter 2.2 --- Methods --- p.70
Chapter 2.2.1 --- Culture of the Tumor Cell Lines --- p.70
Chapter 2.2.2 --- "Isolation, Preparation and Culture of Mouse Peritoneal Macrophages" --- p.70
Chapter 2.2.3 --- Determination of Cell Viability --- p.71
Chapter 2.2.4 --- Determination of Cell Proliferation by [3H]-TdR Incorporation Assay --- p.72
Chapter 2.2.5 --- Determination of Anti-leukemia Activity In Vivo --- p.73
Chapter 2.2.6 --- Analysis of Cell Cycle Profile/DNA Content by Flow Cytometry --- p.74
Chapter 2.2.7 --- Measurement of Apoptosis --- p.75
Chapter 2.2.8 --- Determination of the Mitochondrial Membrane Potential --- p.77
Chapter 2.2.9 --- Measurement of Caspase Activity --- p.78
Chapter 2.2.10 --- Study of Intracellular Accumulation of Reactive Oxygen Species --- p.79
Chapter 2.2.11 --- Gene Expression Study --- p.80
Chapter 2.2.12 --- Protein Expression Study --- p.83
Chapter 2.2.13 --- Measurement of Cell Differentiation --- p.87
Chapter CHAPTER 3: --- STUDIES ON THE ANTI-PROLIFERATIVE EFFECT OF TRYPTANTHRIN AND INDIRUBIN-3'-OXIME ON MYELOID LEUKEMIA CELLS
Chapter 3.1 --- Introduction --- p.90
Chapter 3.2 --- Results --- p.94
Chapter 3.2.1 --- Effects of Indirubin-3'-oxime and Tryptanthrin on the Proliferation of Myeloid Leukemia Cell Lines of Human and Murine Origins In Vitro --- p.94
Chapter 3.2.2 --- Kinetic and Reversibility Studies of the Anti-proliferative Effect of Tryptanthrin on Murine Myelomonocytic Leukemia WEHI-3B JCS Cells In Vitro --- p.108
Chapter 3.2.3 --- Cytotoxic Effect of Tryptanthrin on Murine Myelomonocytic Leukemia WEHI-3B JCS Cells In Vitro --- p.113
Chapter 3.2.4 --- Cytotoxicity of Tryptanthrin on Non-Cancer Cell Line and Primary Myeloid Cells In Vitro --- p.115
Chapter 3.2.5 --- Effects of Tryptanthrin on the Cell Cycle Profile of the Murine Myelomonocytic Leukemia WEHI-3B JCS Cells In Vitro --- p.118
Chapter 3.2.6 --- Effects of Tryptanthrin on the Expression of Cell Cycle Related Genes in Murine Myelomonocytic Leukemia WEHI-3B JCS Cells In Vitro --- p.123
Chapter 3.2.7 --- Expression of CDK-inhibitors in Tryptanthrin-treated Murine Myeloid Leukemia WEHI-3B JCS Cells --- p.126
Chapter 3.2.8 --- Effects of Tryptanthrin on the In Vivo Tumorigenicity of the Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.128
Chapter 3.2.9 --- In Vivo Anti-tumor Effect of Tryptanthrin on Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.130
Chapter 3.3 --- Discussion --- p.132
Chapter CHAPTER 4: --- STUDIES ON THE APOPTOSIS-INDUCING EFFECT OF TRYPTANTHRIN ON MURINE MYELOMONOCYTIC LEUKEMIA WEHI-3B JCS CELLS
Chapter 4.1 --- Introduction --- p.139
Chapter 4.2 --- Results --- p.143
Chapter 4.2.1 --- Induction of DNA Fragmentation by Tryptanthrin in the Murine Myelomonocytic Leukemia WEHI-3B Cells In Vitro --- p.143
Chapter 4.2.2 --- Induction of Phosphatidylserine Externalization by Tryptanthrin in Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.145
Chapter 4.2.3 --- Change of Mitochondrial Membrane Potential of Tryptanthrin- treated Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.147
Chapter 4.2.4 --- Induction of Caspase Activity in Tryptanthrin-treated Murine Myelomonocytic Leukemia WEHI-3B JCS cells --- p.150
Chapter 4.2.5 --- Induction of Reactive Oxygen Species in Tryptanthrin-treated Murine Myelomonocytic Leukemia WEHI-3B JCS cells --- p.155
Chapter 4.2.6 --- Expression of Bcl-2 Family Proteins in the Tryptanthrin-treated Murine Myelomonocytic Leukemia WEHI-3B JCS cells --- p.160
Chapter 4.2.7 --- Effects of Tryptanthrin on the mRNA Expression of Bcl-2 Family Proteins in Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.163
Chapter 4.2.8 --- Expression of Fas and Fas Ligand Proteins in Tryptanthrin-treated Murine Myelomonocytic Leukemia WEHI-3B JCS cells --- p.167
Chapter 4.2.9 --- Expression of Pro-Apoptotic Protein in Tryptanthrin- treated Murine Myelomonocytic Leukemia WEHI-3B JCS cells --- p.170
Chapter 4.2 --- Discussion --- p.173
Chapter CHAPTER 5: --- STUDIES ON THE DIFFERENTIATION-INDUCING ABILITY OF TRYPTANTHRIN ON MURINE MYELOMONOCYTIC LEUKEMIA WEHI-3B JCS CELLS
Chapter 5.1 --- Introduction --- p.184
Chapter 5.2 --- Results --- p.186
Chapter 5.2.1 --- Morphological Studies on Tryptanthrin-treated Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.186
Chapter 5.2.2 --- Effects of Tryptanthrin on the Cell Size and Granularity of the Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.189
Chapter 5.2.3 --- Effects of Tryptanthrin on Induction of NBT-reducing Activity in the Murine Myelomonocytic Leukemia WEHI-3B JCS Cells --- p.191
Chapter 5.3 --- Discussion --- p.195
Chapter CHAPTER 6: --- CONCLUSIONS AND FUTURE PERSPECTIVES --- p.198
REFERENCES --- p.206
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4

Lin, Yeh-Ssu, and 林曄思. "The Effect of Tryptanthrin in MCF-7 Breast Cancer Cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/08668569688413462113.

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Abstract:
碩士
國立臺灣大學
藥學研究所
97
Multidrug resistance (MDR), the resistance of tumor cells to anticancer agents, remains a major cause of treatment failure for cancer patients. MDR usually occurs with alteration of function and expression of some proteins and enzymes, for example P-gp (P-glycoprotein), MRP (multidrug resistance-related protein), topoisomerase and glutathione. Recently, the genes which show differential expressions in MCF-7/WT and its doxorubicin-resistant counterpart MCF-7/ADR include ER-α (estrogen receptor α), ER-β (estrogen receptor β), PR (progesterone receptor), VEGF(vascular endothelial growth factor), HIF-1α ( hypoxia-inducible factor-1α ) , FoxO1(forkhead box-containing protein,O subfamily), C/EBP β(CCAAT/enhancer-binding protein β), CtBP1(C-terminal binding protein 1), dicer 1, argonaute 2, PIM-1 and PKc α (protein kinase c α). Our lab previously demonstrated that tryptanthrin could reverse the resistance to doxorubicin in MCF-7/ADR. In order to extensively understand the mechanisms of multidrug resistance, MCF-7/WT and MCF-7/ADR were treated with trptanthrin to examine the changes in expression of the above genes in this study, using RT-PCR, realtime-PCR and Western blot. Results show that tryptanthrin suppresses the expression of nuclear receptor genes in MCF-7/WT. The expression of ER-α is 50% down. Furthermore, the binding of SP1 family proteins to ER-α promoter site IEF-1 decreases upon tryptanthrin treatment. In mRNA level, tryptanthrin inhibits the expression of PR prior to the expression of ER-α. As PR is downstream protein of ER-α, it seems that tryptanthrin acts on PR and ER-α via different pathways. When ER-α expression was knockdowned by siRNA in MCF-7/WT, the expression of MDR1 gene did not induced, suggesting the decrease in ER-α was not related to MDR1 gene expression in MCF-7/ADR.
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5

Danz, Henning. "Untersuchungen zur antiinflammatorischen Wirkung und zur Analytik von Tryptanthrin in Isatis tinctoria L. /." 2001. http://www.gbv.de/dms/bs/toc/328938807.pdf.

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6

Chung, Chia-Hua, and 鍾佳華. "Effects of tryptanthrin on human hepatoma growth in vitro and in vivo." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/81248671303080476799.

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Abstract:
碩士
國立中興大學
食品暨應用生物科技學系所
99
Hepatocellular carcinoma is a common tumor in Asia and Africa area. Tryptanthrin is a weakly basic alkaloid and has been reported to have various functions, such as anti-microorganisms, anti-parasites, immunomodulatory, anti-inflammatory and anti-tumor activity in vitro. In this study, we examined the efficacy of tryptanthrin in suppression hepatoma growth and further investigated the mechanism by which tryptanthrin alter tumor cell growth. Tryptanthrin significantly inhibited human hepatoma cell proliferation in vitro. However, our data showed that tryptanthrin did not alter expression or activity of caspase proteins, which was different from previous studies on this compound. Tryptanthrin increased intracellular reactive oxygen species and decreased the expression of growth-related proteins. Furthermore, the levels of apoptosis-related protein in the cytoplasmic and nuclear fractions were significantly increased by tryptanthrin treatment. Fluorescence microscope observation further discovered the nuclear translocation of apoptosis-related proteins and their nuclear condensation in tryptanthrin-treated cells. We suggest that tryptanthrin enhanced reactive oxygen species level that led to loss of mitochondrial potential in human hepatoma cells, followed by the activation of apoptotic protein release. The in vivo study subsequently showed that tryptanthrin supplementation inhibited tumor growth in BALB/c nu/nu athymic mice with human hepatoma cell xenograft. Tryptanthrin supplementation increased the number of apoptosis-related protein cells in tumors. The present study suggested that tryptanthrin may have anti-tumor potential in humans.
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7

曾詩韻. "The mechanism of tryptanthrin derivatives DQ150 and EY083 on inhibition of multidrug resistance." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/04382688704669895471.

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碩士
國立臺灣大學
藥學研究所
88
The resistance of tumor cells to anticancer agents remains a major cause of treatment failure for cancer patients. Agents as adjuvants to overcome MDR become a new trend in chemotherapy. We have evaluated the tryptanthrin derivatives DQ150 and EY083 for their reversing activity against P-glycoprotein-(P-gp) and MRP-mediated MDR in breast cancer cell lines MCF7, adriamycin-resistant MCF7/adr and etoposide-resistant MCF7/vp. Using MTT assay, 10-6M of DQ150 and EY083 had a 6-fold and 2-fold decrease in adriamycin IC50, respectively, in MCF7/adr. At mRNA level, DQ150 is more efficient than EY083 to diminish mdr1 (coding for P-gp, a membrane drug efflux pump) and glutathione S-transferase π (a drug detoxification enzyme) overexpression. Nevertheless, a large amount reduction of P-gp expression was observed using western blotting when MCF7/adr cells was treated with EY083 at 10-6M. DQ150 inhibits topoisomerase IIα and β completely, whereas EY083 partially inhibits topo IIα and does not inhibit topo IIβ at all. The compounds DQ150 and EY083 do not influence the mdr1 genomic DNA amplification. On the other hand, DQ150 and EY083 suppress the mdr1 gene at transcriptional level regarding to the influence on the mdr1 promoter regulation by AP-1 and p53. AP-1-DNA interaction was affected by the treatment with DQ150 and EY083 through the mobility shift assay. The amount of p53 decreased significantly when MCF7 were treated with DQ150 and EY083. Taken together, DQ150 and EY083 are likely to reverse P-glycoprotein, GSTπ and topoisomerase II-mediated MDR phenotype and may be as potential anticancer adjuvants in the future. Interestingly, in the MCF7/vp presenting MRP-mediated MDR, 10-6M EY083, but not DQ150, decreased etoposide IC50 15-fold. At mRNA level, EY083 diminished MRP overexpression. The differential inhibition of MRP mRNA expression between DQ150 and EY083 needs future study to unveil the correlation between P-gp- and MRP-mediated MDR.
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8

Yu, Sung-Tsai, and 尤松材. "The mechanism of tryptanthrin derivatives DQ150 and EY083 on inhibition of multidrug resistance." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/68672566595965765092.

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碩士
國立臺灣大學
藥學研究所
89
Chemotherapy is a common and effective treatment for tumors. However, the resistance of tumor cells to anticancer agents remains a major cause of treatment failure in cancer patients. Increased expression in tumor cells of plasma membrane proteins such as the P-glycoprotein (P-gp) or the multidrug resistance-associated protein 1 (MRP1) is often associated with such multidrug resistance (MDR) phenotype. P-glycoprotein and MRP1 both belong to membrane transport proteins of the large ATP-binding cassette (ABC) superfamily but share less than 20% amino acid identity. We have evaluated the tryptanthrin derivatives DQ150 and EY083 for their reversing activity against P-gp and MRP-mediated MDR in breast cancer cell lines MCF-7 and its counter parts, adriamycin-resistant MCF-7 (MCF-7/adr) and etoposide-resistant MCF-7 (MCF-7/vp). Using RT-PCR assay, 10-6M DQ150 is more efficient than 10-6M EY083 to decrease MDR1, glutathione S-transferase π (a drug detoxification enzyme) and MRP1 mRNA overexpression. When MCF-7/adr cells were treated with DQ150 at 10-6M for 5 days, we observed a large amount of reduction of P-gp and GSTπ protein in parallel with decreases in mRNA. In MCF-7/vp, MRP1 protein decreases when treated with 10-6M DQ150. Many studies have provided evidence implicating complex formation for transcriptional regulation of the MDR1 and MRP1 gene promoters in human cancer cells. In addition, wild type p53 can modulate promoter activity of the human MDR1 and MRP1 genes. In MCF-7/adr cells, AP-1 and SP-1, interacting with MDR1 gene promoter, were affected by EY083 at 10-6M through the gel mobility shift assay, while it was not observed when treated with DQ150. However, DQ150 enhanced the NF-κB/p65 and c-Fos transcription factors interacting with the negatively regulatory CAAT region of the MDR1 gene promoter in MCF-7/adr. On the other hand, DQ150 is more efficient than EY083 in the interfering with the interaction of SP-1 and MRP1 gene promoter in MCF-7/vp. The amount of mutant p53 decreased significantly when MCF-7/adr and MCF-7/vp were treated with DQ150 and EY083 at 10-6M. Take together, we conclude that different mechanisms may be involved in the inhibition of MDR1 expression by DQ150 and EY083, while these two compounds inhibit MRP1 expression through similar pathways
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9

Chang, Hsin Ning, and 張心寧. "The anti-psoriatic effect and mechanism of indigo naturalis and its active component, tryptanthrin." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107CGU05521026%22.&searchmode=basic.

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10

Chang, Ya-Lin, and 張雅琳. "Tryptanthrin, a natural product, exhibits novel antifungal activity and cell cycle arrest against Cryptococcus species." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/m87w7q.

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碩士
國立臺灣大學
植物病理與微生物學研究所
106
This study aims to identify bioactive compounds that exert novel antifungal activity alone or exhibit synergistic effect with an existing antifungal agent against human fungal pathogens Cryptococcus and Candida. We screened several compound libraries including natural products, agricultural fungicides and FDA-approved drugs in order to identify compounds that exert antifungal activity. Among selected compounds, tryptanthrin secreted from Nocardiopsis alba, an actinobacterium existed in the intestine of honeybee, was chosen for further characterization because of its potent inhibition activity against Cryptococcus species with the minimal inhibition concentration (MIC) of 2 ug/mL for C. neoformans and 4 ug/mL for C. gattii. We further found that tryptanthrin showed synergistic effect with FK506, an immunosuppressant, based on broth dilution and checkerboard assays. Tryptanthrin inhibits the growth of Cryptococcus cells in a dose-dependent manner and shows fungistatic activity instead of fungicidal. We also found that tryptanthrin is more effective at 37 ºC compared with to 30 ºC or 25 ºC. Meanwhile, tryptanthrin demonstrated antifungal activity against two clinical azole-resistant C. neoformans isolates, T1 and 89-610. In order to identify potential targets or pathways that tryptanthrin involves in, we screened the Cryptococcus deletion mutant library by drug susceptibility test. Forty-nine deletion mutants were found to be more susceptible or resistant than that of the wild-type, and some of these mutants were involved in in cell cycle regulation. Fluorescence-activated cell sorting and gene expression quantification results support that cell cycle regulation in C. neoformans may be linked to tryptanthrin. In summary, the natural product tryptanthrin shows novel antifungal activity alone or in combination with FK506, leading possible therapeutic strategies for cryptococcosis caused by Cryptococcus species, especially the azole-resistant isolates.
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11

Pinheiro, Daniela Ribeiro. "Synthesis, photophysical and electrochemical studies on tryptanthrin and indigo derivatives. Historic molecules with modern applications." Doctoral thesis, 2021. http://hdl.handle.net/10316/95405.

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Tese no âmbito do Doutoramento em Química, ramo de especialização em Fotoquímica, apresentada ao Departamento de Química da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
Indigo, an iconic molecule of colour, is included in the most ancient and important natural dyes used by mankind. The longevity as a colourant and unique properties of this compound are related with its high (photo)stability which is linked to a rapid proton transfer in the excited state (ESPT). In the past few years, indigo and its derivatives have gained renewed interest due to applications in several fields such as photoswitches, electronic devices and sensors. The study and development of an improved and fast approach for the synthesis of mono- and di-substituted indigo derivatives combined with a comprehensive characterization of their electronic spectral and photophysical properties in different solvents and temperatures was undertaken and constitutes the first part of this thesis. The study was further rationalized with density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations. The second part of this thesis reports the synthesis of tryptanthrin and tryptanthrin derivatives, important compounds with a variety of biological and pharmacological applications as well as redox properties. Tryptanthrin was synthesized from indigo under mild conditions using microwave irradiation. A comprehensive study of the excited state of these compounds was also undertaken. In contrast with indigo, emission of the triplet state of tryptanthrin and its derivatives, with the exception of 2-aminotryptanthrin, where fluorescence dominates, was observed with a very efficient singlet oxygen sensitization quantum yield. These results indicate intersystem crossing (ISC) to be the dominant deactivation channel in tryptanthrin and its derivatives, with high quantum yields. Time-resolved fluorescence and femtosecond transient absorption (fs-TA) data, further supported with TDDFT calculations, show for tryptanthrin, two species, a locally excited (LE) and a charge transfer (CT) with a highly reversible inter-conversion rate constant (LE to CT state). A pratical and modern application of storage of chemical energy with, an aqueous organometallic and an all-organic redox flow battery (RFB) with sulfonated tryptanthrin, working at neutral pH and with long-term stability, was further developed. The single cell tests showed reproducible charge-discharge cycles with significant improvement results for the aqueous all-organic RFB, with higth coulombic, voltaic and energetic efficiencies stabilized over several working cycles. The work paves the way to the promising development of new tryptanthrin based structures for environmentally friendly aqueous all-organic RFBs working at neutral pH values.
O índigo, uma icónica molécula da cor, é um dos corantes mais antigos e importantes usados pela humanidade. A longevidade deste corante assim como as suas propriedades únicas estão relacionadas com a sua elevada (foto)estabilidade que esta ligada a uma rápida transferência de protão no estado excitado. Nos últimos anos, o índigo e os seus derivados ganharam um interesse renovado devido a aplicações em diversos campos, tais como, interruptores fotónicos, dispositivos elétricos e sensores. O estudo e desenvolvimento de uma abordagem mais rápida e aprimorada da síntese de derivados mono- e di-substituídos do índigo combinados com uma caracterização abrangente das suas propriedades eletrónicas, espectrais e fotofísicas, em diferentes solventes e temperaturas foi realizada e constitui a primeira parte desta tese. O estudo foi racionalizado com cálculos teóricos através da teoria do funcional da densidade (DFT) e da teoria do funcional da densidade dependente do tempo (TDDFT). A segunda parte desta tese relata a síntese da triptantrina e seus derivados. Estes compostos são importantes pois para além de apresentarem uma vasta aplicação biológica e farmacológica possuem também propriedades de oxidação-redução. A triptantrina foi sintetizada a partir do índigo sob condições suaves utilizando radiação de micro-ondas como fonte de energia. Um estudo abrangente do estado excitado destes compostos foi também realizado. Em contraste com o índigo, na triptantrina e seus derivados, com exceção da 2-aminotriptantrina, onde a fluorescência domina, foi observada emissão do estado tripleto com rendimentos quânticos de formação de oxigénio singleto muito eficientes. Estes resultados indicam que a conversão intersistemas (ISC) é a principal via de desativação na triptantrina e seus derivados, com elevados rendimentos quântico. Os dados de fluorescência resolvida no tempo e absorção transiente de femtosegundos (fs-TA), complementados com cálculos TDDFT, mostram que no caso da triptantrina, existem duas espécies, uma excitada localmente (LE) e uma com transferência de carga (CT), com uma constante de interconversão altamente reversível (LE para o estado CT). Uma aplicação prática e moderna de armazenamento de energia química com, uma bateria redox de fluxo aquoso organometálico e exclusivamente orgânico com triptantrina sulfonada, trabalhando em pH neutro com estabilidade a longo prazo foi desenvolvida. Os testes de célula única demostraram ciclos de carga-descarga reprodutíveis, com melhores resultados no sistema exclusivamente orgânico, com eficiências coulômbica, voltaica e enérgicas estáveis e elevadas ao longo de vários ciclos. Este trabalho fornece uma nova perspetiva sobre o desenvolvimento de derivados da triptantrina solúveis em água com potencial aplicação em baterias de fluxo aquoso de sistemas exclusivamente orgânico que trabalham em pH neutro e são mais sustentáveis em termos ambientais.
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12

Wu, Hsing-Hung, and 吳信宏. "Studies on the Effects of Tryptanthrin and Its Derivative FV195 in Human Hepatoma Cell Line HuH7." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/46793140870304843982.

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13

Chen, Chia Sheng, and 陳佳聖. "The mechanism of tryptanthrin derivative DQ150 on inhibition of multidrug resistance in drug-resistant breast cancer lines." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/51937002512662796206.

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14

Oberthür, Christine [Verfasser]. "Indolische Sekundärmetabolite in Isatis tinctoria L. : Hautpenetration von Tryptanthrin und saisonale sowie prozessbedingte Veränderungen der Inhaltsstoffmuster / von Christine Oberthür." 2004. http://d-nb.info/97206639X/34.

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15

Surup, Frank. "Metagenom-Technologie zur Wirkstoffsuche sowie Untersuchungen der Iromycine aus Streptomyces sp." Doctoral thesis, 2007. http://hdl.handle.net/11858/00-1735-0000-0006-ACA7-B.

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