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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

淺論武夷肉桂茶的中醫學功效

陳澤楠, 11 June 2016 (has links)
本文主要通過查閱和收集近年來有關武夷肉桂茶及茶葉研究相關的文獻和文章,介紹了武夷肉桂茶的產地、生物特性、製作工藝、審評、他學組分、相關藥理作用的研究等各方面的內容。分析了武夷肉桂茶的性味歸經、中醫學功效進而提出了目前的研究中尚存的一些問題,以及對茶療這一療法今後的研究和發展方向表達了自己的見解。 武夷肉桂茶,無性奈、灌木型、小葉類、中晚生種。原產於國家一級自然保護區武夷山,香氣辛銳濃長似桂皮香。其含有多種營養成分和藥理活性成分,如茶多盼、茶氯酸、咖啡鹼、茶多糖、複合糖、茶皂素、有機酸、芳香物質、類胡蘿蔔素、葉綠素、黃闢類、維生素C 、多種B 屬維生素、維生素P 及磷、主甲、鈣、鎮、鋒、氣、晒等礦物元素,均為人體保健的功能性物質。 經過武夷岩茶的製作工藝後的肉桂茶,其性味表現為“味辛,甘,苦,性溫’歸心、肺、腎、胃經。具有發汗解肌、補火助陽、他氣行水、溫經通絡、溫通心陽、溫脾胃、提神醒腦等功效。可用於治療外戚表邪、膀恍氣化失常、痛痹、心陽不振、下元虛冷、脾胃虛寒等證。 近年來研究資料顯示:武夷肉桂茶中的有效成分具有抗菌抗病毒、增強免疫力、利尿、抗炎、降血脂和抗動脈粥樣硬化、抗凝血及抗血桂、降壓、降血糖、對中樞性和末梢性血管系統的興奮和強心作用等因此,肉桂茶可用於外戚風寒、前列腺增生、月經不調、精神不振、風濕性關節炎、類風濕性關節炎、冠心病、高血壓、高血脂、高血糖、胃腸疾病、等防治以及日常養生。 然而,對於武夷肉桂茶乃至整個茶療體系的研究還是存在著一些問題,例如沒有從中醫方面進行有關療效的闡述等。所以,我們在瞭解中醫茶療歷史的前提下及茶葉組分的藥理研究的背景下,應當重新審視茶的醫療保健價值,開拓臨床治療及養生保健的新思路。
2

Maternal green tea epigallocatechin gallate supplementation counteracts high-fat diet-induced metabolic derangements in dams andtheir male offspring: a programming effect

Li, Shiying, 李诗盈 January 2012 (has links)
The overall objective of this thesis was to test the hypothesis that through developmental programming maternal overnutrition-induced metabolic derangements in the offspring could be offset by supplementing the maternal diet with green tea epigallocatechin gallate (GTEG). The obesogenic diet was a high-fat (HF, 30%) diet. Female Sprague-Dawley rats were fed the HF, low-fat (LF, 7%) or HF diet containing 0.75% or 1.0% GTEG (GT1, GT2) from before conception and throughout gestation and lactation. Both doses of GTEG significantly improved metabolic control of the HF-fed lactating dams. The weaned male pups received the HF, GT1 or GT2 diet forming 6 dam/pup groups: LF/HF, HF/HF, HF/GT1, HF/GT2, GT1/HF and GT2/HF. At wk 13 they had similar weight but insulin resistance index (IRI), serum non-esterified fatty acid (NEFA) and liver triglyceride of rats born to GTEG dams was 57, 23 and 26% lower and accompanied by improved gene/protein expressions related to lipid and glucose metabolism compared to HF/HF rats (P < 0.05). Although the HF/GT1 and HF/GT2 rats had lower serum NEFA, their serum insulin and IRI remained comparable with the HF/HF rats. To determine if there is a critical time period for the actions of GTEG, in the second experiment female rats were fed the LF, HF, or GT1 diet prior to conception and throughout gestation. During lactation, half of the dams had their diet switched from HF to GT1 and vice versa. Pups were weaned to the HF or LF diet, forming the LF/LF/LF, LF/LF/HF, HF/HF/LF, HF/HF/HF, HF/GT1/LF, HF/GT1/HF, GT1/GT1/LF, GT1/GT1/HF, GT1/HF/LF and GT1/HF/HF groups. Metabolic controls of dams given GT1 during gestation or lactation were improved compared with the HF/HF dams (P < 0.05). Three-way ANOVA revealed that 22 wk old offspring born to dams fed the HF diet during gestation had higher serum and muscle triglyceride (TG) concentration and lower ferric reducing ability of plasma (FRAP) (P < 0.05), all of which were reversed by supplementing GT1 to the gestational diet. Oral glucose tolerance at wk 15 was improved in those offspring born to dams given GT1 supplementation during lactation (P < 0.05). The increased serum NEFA concentration and IRI in offspring of dams fed the HF diet during gestation or lactation were reversible upon GT1 supplementation during either time period (P < 0.05). These rats (HF/GT1/HF, GT1/GT1/HF and GT1/HF/HF) had similar level of hepatic insulin receptor gene expression as well as protein abundance for muscle glucose transporter 4 and hepatic sterol regulatory element binding protein-1c but lower protein mass for hepatic glucose-6-phosphatase (P < 0.05) compared with the LF/LF/HF rats. Hence, maternal overnutrition-induced metabolic derangements in male offspring are reversible through supplementing GTEG to the maternal diet during gestation or lactation and this approach is more effective than giving GTEG to offspring born to overnourished mothers. Offspring metabolism could be programmed via manipulations of the maternal diet. / published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy
3

Effects of green tea on ovariectomized rats

何禮昌, Ho, Lai-cheong. January 2002 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
4

Effect of green tea on diet-induced obesity in rats

麥丹, Mai, Dan, Karen. January 2001 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
5

The inhibitory effect of rooibos on cytochromes P450 and downstream in vitro modulation of steroid hormones

Mugari, Mufaro Buhlebenkosi 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This study describes: 1. Substrate binding assays investigating the effects of methanolic extracts of unfermented and fermented Rooibos on the binding of natural substrates to ovine adrenal microsomal and mitochondrial P450 enzymes, demonstrating the interference of substrate binding in the presence of the Rooibos extracts. 2. The effects of selected flavonoids (quercetin, rutin and aspalathin) on the binding of natural substrates to ovine adrenal microsomal and mitochondrial P450 enzymes, demonstrating interference of substrate binding in the presence of the flavonoid compounds. 3. Substrate conversion assays in non-steroidogenic COS-1 cells to investigate the effects of methanolic extracts of unfermented and fermented Rooibos on the activity of key steroidogenic P450 enzymes (CYP17A1, CYP21A2, CYP11B1, and CYP11B2), demonstrating inhibition of the catalytic activity in the presence of Rooibos extracts. 4. The effects of selected flavonoids on the substrate conversion of the aforementioned key steroidogenic enzymes expressed in COS-1 cells. 5. An investigation of the effect of methanolic extracts of unfermented and fermented Rooibos on steroid hormone production in human adrenal H295R cells under basal and stimulated conditions, demonstrating the modulating effects of unfermented and fermented Rooibos extracts. Basal and stimulated steroid hormone production was decreased in the presence of unfermented and fermented Rooibos. / AFRIKAANSE OPSOMMING: Hierdie studie beskryf: 1. Die gebruik van substraatbindings-essais om die effek van metanoliese ekstrakte, van gefermenteerde- en ongefermenteerde Rooibos, op die binding van die natuurlike substrate aan skaap adrenale mikrosomale en -mitochondriale P450 ensieme te bepaal. Daar is getoon dat die ekstrakte 'n beduidende inhiberende effek op ensiemsubstraatinteraksie gehad het. 2. Die die inhiberende effek van geselekteerde flavonoïede (kwersetien, rutien and aspalatien) op die binding van die natuurlike substrate aan skaap adrenale mikrosomale en -mitochondriale P450 ensieme. 3. Die gebruik van substraatomsettings-essais in nie-steroïedogeniese COS-1 selle, om die effek van gefermenteerde- en ongefermenteerde Rooibos ekstrakte op die aktiwiteit van die steroïedogeniese P450 ensieme (CYP17A1, CYP21A2, CYP11B1, and CYP11B2) se katalitiese aktiwiteit te bepaal. Daar kon aangetoon word dat die katalitise aktiwiteite van bg. ensieme beduidend beïnvloed word deur die Rooibos ekstrakte. 4. Die gebruik van substraatomsettings-essais in nie-steroïedogeniese COS-1 selle, om die effek van geselekteerde flavonoïede op die aktiwiteit van bogenoemde steroïedogeniese P450 ensieme te bepaal. 5. 'n Ondersoek na die invloed van metanoliese ekstrakte van gefermenteerde- en ongefermenteerde Rooibos op steroïedhormoon biosintese in die menslike adrenale H295R-selmodel. Die ondersoek, onder basale en gestimuleerde toestande, het getoon dat beide Rooibosekstrakte in bogenoemde toestande steroïedhormoon produksie geinhibeer het.
6

An investigation into the influence of rooibos (Aspalathus linearis) on androgen metabolism in normal and prostate cancer cells

Du Toit, Therina 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In this study, the influence of rooibos on the catalytic activity of enzymes 17β -hydroxysteroid dehydrogenase type 3 (17βHSD3), 17β-hydroxysteroid dehydrogenase type 5 (AKR1C3), 17β-hydroxysteroid dehydrogenase type 2 (17βHSD2), 5α-reductase type 1 (SRD5A1) and 5α-reductase type 2 (SRD5A2), which catalyse prostate androgen metabolism, was investigated. The activities of both 17βHSD3 and AKR1C3 heterologously expressed in CHO-K1 and HEK293 cells were inhibited significantly by rooibos, with rooibos reducing the conversion of androstenedione (A4) and 11keto-androstenedione (11KA4) to testosterone (T) and 11ketotestosterone (11KT), respectively. The catalytic activity of 17βHSD2 towards T, 11hydroxytestosterone (11OHT) and 11KT was also significantly inhibited by rooibos in transiently transfected HEK293 cells. In transiently transfected HEK293 cells rooibos did not inhibit SRD5A1 while the rate of T conversion to dihydrotestosterone (DHT) by SRD5A2 was decreased. Analysis of steroid metabolism in PNT2 cells also suggests that rooibos does not modulate the catalytic activity of endogenously expressed SRD5A towards A4, however, the conversion of T to DHT was reduced. In addition, reductive 17βHSD activity towards A4 was inhibited in the presence of rooibos in both PNT2 and BPH-1 cells. In contrast, the conversion of 11KA4 to 11KT was inhibited in BPH-1, PC-3 and LNCaP cells, with negligible conversion of 11KA4 in PNT2 cells. Interestingly, data suggests inhibition of 3α-hydroxysteroid dehydrogenase type 3 (AKR1C2) activity in the production of androsterone (AST) from 5α–androstenedione (5α-dione), as well as the dehydrogenase reaction of T to A4 in PNT2 cells by rooibos. Androgen metabolism pathways were subsequently investigated in LNCaP cells to determine androgen metabolism by endogenous enzymes. Rooibos resulted in the reduced conversion of A4 in LNCaP cells to the same extent as indomethacin, a known AKR1C3 inhibitor. Rooibos also modulated T, DHT and AST metabolism in LNCaP cells. Furthermore, uridine diphosphate glucuronosyltransferase (UGT) activity in LNCaP cells was inhibited by rooibos, decreasing T-, DHT– and AST-glucuronide formation. These data prompted subsequent investigations into the influence of rooibos at cellular level, and prostatespecific antigen (PSA) levels were assayed in the presence of rooibos. PSA was significantly inhibited by rooibos in the absence and presence of DHT, suggesting possible interaction of rooibos with the mutated androgen receptor (AR) or estrogen receptor-β (ERβ) expressed in LNCaP cells. Taken together, rooibos inhibited the catalytic activity of key enzymes that catalyse the activation of androgens in the prostate, as well as inhibiting enzymes involved in the conjugation of androgens. At cellular level, PSA levels were also decreased by rooibos, possibly through AR or ERβ interactions – clearly indicating a modulatory role for rooibos in active androgen production. / AFRIKAANSE OPSOMMING: In hierdie studie was die invloed van rooibos ten opsigte van die katalitiese aktiwiteite van die ensieme 17β-hidroksi-steroïed-dehidrogenase tipe 2, tipe 3 en tipe 5 (17βHSD2, 17βHSD3, AKR1C3), asook 5α-reduktase tipe 1 en tipe 2 (SRD5A1, SRD5A2) ondersoek. Hierdie ensieme is betrokke in die produksie van androgene in die prostaat. Rooibos het die katalitiese aktiwiteit van 17βHSD3 en AKR1C3 in CHO-K1 en HEK293 selle beïnvloed en het vermindere omskakeling van androstenedioon (A4) en 11keto-androstenedioon (11KA4) na testosteroon (T) en 11-ketotestosteroon (11KT), afsonderlik, veroorsaak. Die katalitiese aktiwiteit van 17βHSD2 teenoor T, 11-hidroksie-testosteroon (11OHT) en 11KT was ook beïnvloed in die teenwoordigheid van rooibos in HEK293 selle. Die katalitiese aktiwiteit van SRD5A1 teenoor A4 en T is nie beïnvloed deur rooibos nie, alhoewel dit voorkom asof rooibos die omsettingstempo van T na dihidrotestosteroon (DHT) deur SRD5A2, getransfekteer in HEK293 selle, verminder het. Verdere ondersoeke is in normale prostaat epiteel selle, in die teenwoordigheid van rooibos uitgevoer. Rooibos het geen invloed op die katalitiese aktiwiteit van SRD5A teenoor A4 gehad nie, alhoewel vermindere omskakeling van T na DHT aangetoon kon word. Rooibos het ook die omskakeling van A4 na T in beide PNT2 en BPH-1 selle tot „n mate geïnhibeer. Die omskakeling van 11KA4 na 11KT was ook verminder in BPH-1, PC-3 en LNCaP selle. Die omskakeling van 11KA4 na 11KT was beduidend laer in PNT2 selle en kon die invloed van rooibos nie aangetoon word nie. Bykomende data toon dat rooibos ook die omskakeling van 5α-androstenedioon (5α-dione) na androsteroon (AST), gekataliseer deur 3α-hidroksi-dehidrogenase tipe 3 (AKR1C2), verminder, gesamentlik met die vermindere omskakeling van T na A4, deur 17βHSD2, in PNT2 selle. Hierdie studie het ook ondersoek ingestel, na die metabolisme van androgene in LNCaP selle. Vermindere A4 metabolisme is in die teenwoordigheid van rooibos asook in die teenwoordigheid van indometasien, „n bekende AKR1C3 inhibitor, gevind. Rooibos verminder dus die aktiwiteit van reduktiewe 17βHSD in LNCaP selle. Verandering in die metabolisme van T, DHT en AST in LNCaP selle, in die teenwoordigheid van rooibos, is ook gevind. Verdere ondersoek in LNCaP selle het gewys dat rooibos „n vermindering in die produksie van gekonjugeerde T, DHT en AST veroorsaak. Die studie het die invloed van rooibos op prostaat-spesifieke antigeen (PSA) ook ondersoek. Daar is vasgestel dat rooibos die vlakke van PSA verminder in die afwesigheid en teenwoordigheid van DHT in LNCaP selle. Hierdie resultaat dui op moontlike interaksie van rooibos met die androgeen (AR) of estrogeen-reseptor-β (ERβ), teenwoordig in LNCaP selle. Rooibos het die katalitiese aktiwiteit van ensieme, wat bydra tot androgeen produksie, geïnhibeer, asook die konjugasie van androgene. Op „n sellulêre vlak, het rooibos die vlakke van PSA-sekresie verminder, wat moontlike interaksie met die AR en ERβ aandui. Hierdie bevindings dui daarop dat rooibos wel n rol het om te speel in die modulasie van aktiewe androgene in die prostaat.
7

Growth inhibition effects of green tea and epigallocatechin gallate inbladder tumors

Chen, Jie, Jack, 陳杰 January 2003 (has links)
published_or_final_version / Pharmacology / Doctoral / Doctor of Philosophy
8

Pharmacological studies of Ilex latifolia--: hypoglycemic and hypolipidemic effects and lack of acute toxicity of Ilex latifolia extract and its saponin-enriched fraction.

January 2000 (has links)
by Fok Ho Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 114-120). / Abstracts in English and Chinese. / Acknowledgements --- p.ii / Abstract --- p.iii / 槪論 --- p.v / List of Abbreviations --- p.vi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Toxicological studies on the effect of Ilex latifolia extract and its saponin-enriched Fraction --- p.19 / Chapter Chapter 3 --- Hypoglycemic effect of Ilex latifolia extract and its saponin-enriched fraction --- p.51 / Chapter Chapter 4 --- Hypolipidemic effect of Ilex latifolia extract and its saponin-enriched fraction --- p.78 / Chapter Chapter 5 --- Conclusion --- p.109 / References --- p.114
9

Antioxidative and vascular relaxing effects of black tea theaflavins. / CUHK electronic theses & dissertations collection

January 2003 (has links)
by Su Ya Lun. / "August 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 163-181). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
10

Offsetting the impacts of maternal and postnatal overnutrition: effects of maternal green tea extractsupplementation on expression of central metabolic regulators inoffspring

Yeung, Oi-yee., 楊藹怡. January 2012 (has links)
The overall objective of this thesis was to test the hypothesis that maternal overnutrition has adverse effects on the expression of central metabolic regulators in offspring but could be offset by supplementing green tea extract (GTE) to the dams during gestation and/or lactation. This thesis focuses on two aspects of central metabolic regulation: the leptin signaling that links to appetite regulation and the sirtuin 1(SIRT1)/oxidative stress pathway that links to insulin sensitivity (IS). This study was initiated based on previous findings of this laboratory that via developmental programming energy intake of offspring born to dams given GTE during lactation was suppressed and that IS was improved in offspring of dams supplemented with GTE during gestation and/or lactation. The diets used included low fat (LF), high-fat (HF), and HF diet added with 0.75% or 1%GTE (GT1, GT2). In experiment 1, female rats were given the respective diet 8 weeks prior to mating till the end of lactation. Male offspring were weaned to the HF, GT1 or GT2 diet for 10 weeks forming the LF/HF, HF/HF, GT1/HF, GT2/HF, HF/GT1 and HF/GT2 groups. Maternal and postweaning GTE supplementation increased hypothalamic leptin receptor (OB-Rb) and signal transducer activator of transcription 3 (STAT3) mRNA suggestive of enhanced leptin signaling but pro-opiomelanocortin (POMC) mRNA expression, an appetite inhibitor was only elevated in the HF/GT1 group which was associated with reduction in food intake in this group. Central oxidative status was improved in GT1/HF and GT2/HF offspring through enhanced hypothalamic SIRT1 and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) expression compared with the HF/HF group. These improvements coincided with better IS in the HF offspring born of GTE supplemented dams. Experiment 2 was designed to determine the relative importance of gestation and lactation as the critical period for GTE supplementation. Female rats were assigned to LF, HF or GT1 diet 9 weeks prior to mating till the end of pregnancy. During lactation half of the HF and GT1 dams had the diet switched to GT1 and HF, respectively. Male offspring were fed the LF or HF diet until 22 weeks of age forming 10 offspring groups: LF/LF/LF, LF/LF/HF, HF/HF/LF, HF/HF/HF, HF/GT1/LF, HF/GT1/HF, GT1/HF/LF, GT1/HF/HF, GT1/GT1/LF, and GT1/GT1/HF. Consistent with a reduction in energy intake in offspring born to dams receiving GTE supplementation during lactation, there was an increase in melanocortin 4 receptor (MC4R) expression in the hypothalamus (P<0.05). Regardless of postweaning diet, offspring of dams given GTE during gestation and/or lactation had elevated hypothalamic PGC-1α and reduced protein phosphorylation of c-Jun N-terminal kinase-1 when compared with offspring of unsupplemented dams(P<0.05) which was associated with improved IS. Hence, leptin signaling and appetite regulators in the offspring were selectively affected by GTE supplementation during lactation whereas offspring exhibited improved ability to handle oxidative stress if dams received GTE supplementation during gestation and/or lactation. Collectively, these results support the notion that central mechanisms with roles in appetite control and oxidative status are susceptible to the programming phenomenon triggered by maternal nutritional status. / published_or_final_version / Biological Sciences / Master / Master of Philosophy

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