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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.
501

The study of the impact of selected mutations in FMS-like Tyrosine Kinase III (FLT3) and Nucleophosmin (NPM1) - and HIV status on patients with acute Myeloid Leukemia and their response to induction therapy.

Naidoo, Horacia. January 2012 (has links)
Acute Myeloid Leukemia (AML), the most common form of acute leukemia in adults, is only curable in approximately 30% of all cases. Despite prognostic risk stratification using sub-typing and cytogenetic analysis to direct therapy, the mortality and relapse rate remains high. AML patients with normal karyotypes are defined as intermediate risk and are the most challenging to treat. Somatic mutations may be the key in refining prognostic stratification and providing useful therapeutic targets. The FMS-like tyrosine kinase 3 (FLT3) and Nucleophosmin (NPM1) genes have common mutated forms that are associated with overall survival and response to therapy. We assessed mutations in the FLT3 and NPM1 genes and their levels of expression in twenty eight AML patients in the presence and absence of HIV and their response to induction therapy. Furthermore, we used a novel technique, High Resolution Melting (HRM) Analysis to detect FLT3 Internal Tandem Duplications (ITD) and NPM1 exon 12 mutations. Five of the patients in this study were HIV positive, three of whom did not survive post-induction therapy. Of the AML patients, 17.9% were positive for the NPM1 mutation and 21% had mutated FLT3. Interestingly, the presence of the FLT3 and NPM1 mutations were coupled with an increase in expression levels of FLT3 and NPM1 from presentation to post-induction respectively and the loss of these mutations were coupled with a decrease in levels of expression from presentation to post-induction. However, an increase/decrease from presentation to post-induction did not necessarily denote the presence/absence of a mutation. Therefore, while mutational status of genes may generally confer mRNA levels, our results showed that there existed no definitive trend between mRNA levels of NPM1 and FLT3 expression and mutational status. We found that the HRM method was definitive for the simpler NPM1 mutation however detection of the FLT3-ITD mutation was challenging. There isn’t a clear distinction between mutated and non-mutated FLT3 due to the formation of hetero-duplexes during analysis, making detection highly subjective and error-prone. Sequencing allowed confirmation of mutated FLT3 and non-mutated FLT3 which were not in all instances in concordance with HRM analysis. The prognostic value in terms of overall survival of NPM1 and FLT3 mutations in this study is indefinite. Furthermore, the analysis of the HIV positive AML patients revealed no clear correlation between NPM1 and FLT3 levels of mRNA expression and mutational status. Also, the small number of HIV positive AML patients did not allow for conclusions to be made regarding HIV status and survival when affected with AML. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
502

How do clinical psychologists make sense of their early attachments and their work with older adults?

Heinson, Charles January 2013 (has links)
Background: attachment theory provides an account of human behaviour across the lifespan, has a strong theoretical foundation and is clinical applicable. It is particularly relevant to older adults, who are often exposed to a greater number of losses. Despite a growing awareness of increasing life expectancy worldwide, services for older adults in the NHS remains under-resourced. However, increased exposure to death and loss in the work might result in clinical psychologists being more reluctant to choose this specialism and may raise issues about their own early attachment experiences. Therefore, it is important to understand how clinical psychologists approach the complexities of their work in light of their own early attachment experiences. Qualitative research of the lived experiences of clinical psychologists is sparse and to date there are no studies addressing this specific issue. Aims: this is an exploratory study which addresses a gap in the literature. The aims are to capture the early attachment experiences of clinical psychologists specialising in working with older adults. It is hoped that the outcome of the study will shed some light on the characteristics of this under-researched group and how they manage the challenges of the work. Methodology: a semi-structured interview schedule was developed to explore how clinical psychologists make sense of their work with older adults in light of their early attachment experiences. Interviews were carried out with five clinical psychologists working in specialist older adult services. The transcripts of the interviews were then analysed using Interpretative Phenomenological Analysis (IPA). Results: the analysis of the five interviews yielded five main themes – “Making sense of early attachment relationships”, “Developing identity in childhood and adolescence”, “Understanding of decision to work with older adults”, “Work with older adults as both challenging and rewarding” and “The person within the professional”. Each of the main themes and their subthemes were supported by excerpts from narratives of participants experiences. Implications: this study highlighted several research and clinical implications. First, the role of non-parental childhood attachments in the development of internal working models is currently an under-researched area which may provide important insights into resilience factors in the face of childhood adversity. Second, clinical implications suggest that access to older adult work early on in the career of clinical psychologists may increase desirability of working in specialist services. Third, the study supports attachment theory as a useful approach to understanding the work with older adults and as a valuable area for the professional development of clinical psychologists. Finally, systemic working with older adults remains an important part of the work which would benefit from further research in this area.
503

A homoeopathic drug proving of ivory from the male African elephant (Loxodonta africana) with a subsequent comparison to Lac Loxodonta africana

Forbes, Barry January 2008 (has links)
Thesis (M.Tech.: Homoeopathy)--Durban University of Technology, 2008 / Introduction This dissertation entails a homoeopathic proving of ivory from the male African elephant (Loxodonta africana) 30CH with a subsequent comparison to Lac Loxodonta africana. Objectives The primary objective of this proving was to determine the effects of homoeopathically prepared ivory from the male African elephant (Loxodonta africana) in a 30CH dilution and was achieved by administering the remedy to a group of healthy individuals (provers) who will document all symptoms that arise as a result of taking the remedy. These symptoms will be used to identify the therapeutic indications of homoeopathic ivory. With these specific indications being documented the remedy can then be utilized in the sick individual, that present with similar symptoms, to induce a cure. A further objective of this proving is to report any variation that may exist in the comparison of two remedies, namely Lac Loxodonta africana (milk derived from the African elephant) and the remedy used in this proving, ivory from the male African elephant (Loxodonta africana). Methodology The substance was triturated up until the 3CH and subsequently converted into a liquid potency to be potentised up until the 30CH. Granules were then impregnated with the 30CH liquid potency. Ten impregnated granules were then placed in each individual ii lactose powder sachets. A total of six powders were dispensed to the proving participants. The proving was conducted as a double blind placebo controlled study with a total of twenty-six (26) provers that met the inclusion criteria (Appendix A). The group was made up of both homoeopathic students as well as the general public of varying ages, race and gender. The total group was randomly divided into two groups, twenty (20) of which received the homoeopathic remedy, the remainder (6) received placebo. A full case history of each prover was taken before commencing the proving as well as on completion of the study. Each individual prover kept a journal, starting a week before the proving, which was continued while taking the remedy and ceased when all symptoms had abated. Once all provers had completed the proving, the information received from the provers through the journals from both groups was collated, assessed and analyzed. A comparison was then made between this proving and Lac Loxodonta africana to assess whether any similarities or differences were evident. The comparison was made on symptom similarities and rubric analysis. Results The proving of ivory from the African elephant (Loxodonta africana) revealed a variety of symptoms. A total of 32 systems were affected in the twenty provers who received the remedy. 716 symptoms were recorded, 83 of which were new symptoms. The systems that were predominately affected were the mind, head and extremities. Many symptoms were confirmed to be similar to those identified in the proving of Lac Loxodonta africana, though differences were also acknowledged. / M
504

A phenomenological investigation of client perceptions of their relationships to co-leaders in process groups

Wood, Benjamin 14 May 2010 (has links)
This dissertation examines the question how do group therapy members perceive the therapeutic relationship in process group therapy? The study fits within the interpretivist paradigm and employs a phenomenological qualitative research approach (Moustakas, 1994). The theoretical framework used to orient the study drew on process group theory according to Rutan, Stone, and Shay’s (2007) psychodynamic group psychotherapy approach and Yalom and Leszcz’s (2005) interpersonal process model of group psychotherapy. Participants were 10 university counseling center clients who were members of process therapy groups at a large urban university. Data collection consisted of in-depth interviews and demographic questionnaires. Phenomenological data analysis procedures followed recommendations by Creswell (2007) and Moustakas (1994). To enhance the rigor and trustworthiness of the study, the researcher engaged in member checking, use of an external auditor, reflexive and methodological journaling, and negative case analysis. Results of the study are presented as descriptions of how participants perceived the therapeutic relationship and the relationship’s influence on the experience of group therapy. Eight categories emerged from the interviews: (a) presence of group leaders; (b) safety; (c) caring; (d) sharing; (e) running the group; (f) levels of leadership; (g) developing understanding; and (h) intimacy with boundaries. Categories consisted of one or more related themes. There is a consideration of how the researcher’s experiences and beliefs played a role in the study. The results are discussed in relation to relevant group therapy theory and research. Strengths, weaknesses, and considerations of the study findings are offered. Implications of the study findings for group therapy practice and research are noted.
505

Synthesis and evaluation of nitrogen-and phosphorus-donor platinum and gold complexes as anti-cancer agents

16 March 2010 (has links)
Ph.D. / Chapter 1 presents a brief overview on the development of platinum, ruthenium and gold anti-cancer complexes. The clinical success of cisplatin has been a tremendous impetus for the design of metal-based antitumor drugs. Its mechanism of action is therefore briefly discussed, as well as the toxic side effects of its clinical use and the cellular resistance to the drug. It is its side effects and drug resistance that have stimulated the development of cisplatin analogues and other metal based anti-cancer agents. Compounds showing most promise are ruthenium complexes which are structurally different but have the same stability and show similar modes of binding to DNA. The last part of the introduction deals with the development of gold(I) and gold(III) complexes, the main topics of the research described in this thesis. Chapter 2 reports on the attempted preparation of dppf and dippf gold(III) complexes. However, the reaction of these diphosphines with H[AuCl4] and Na[AuCl4] all led to isolation of gold(I) complexes (dppf)Au2X2 (X = Cl (1), Br (3)) and (dippf)Au2X2 (X = Cl (2), Br (4)). In an attempt to oxidize the gold(I) complexes, (dppf)Au2Br2 (3) and (dippf)Au2Br2 (4) were reacted with excess bromine yielding two new complexes (C5H4Br3)(PR2)AuBr (R = Ph, 5; R = i-Pr, 6). This bromination reaction could be extended to the ligands and bromination of the free diphosphinoferrocene ligands produced the expected brominated cyclopentenes (C5H4Br3)(PR2) (R = Ph, 7; R = i-Pr, 8) in good yields. However, these could not be complexed to gold due to reduced basicity of 7 and 8. When the bromination was performed under wet aerobic conditions the oxidized pseudo-centrosymmetric product, [doppf][FeBr4] (9) {doppf = 1,1’-bis(oxodiphenylphosphino)ferrocene, was obtained as the major product. Solid-state structures of 1, 2, 4, 6, and 9 were established by means of single-crystal X-ray crystallography. Chapter 3 reports on the use of chiral Josiphos and Walphos diphosphine ligands to form palladium, platinum and gold complexes. The platinum complexes were prepared by reacting the ligands with [PtCl2(cod)] while the palladium complexes were prepared from [PdCl2(NCMe)2]. The complexes obtained had the general formula [MCl2(P-P)], where M = Pd, Pt, and P-P = Josiphos or Walphos ligand, and were obtained in good yields. The X-ray structures of a palladium(II) and a platinum(II) complex of the same Josiphos ligand were determined. The Josiphos complexes 12 and 14 show good solubility in common solvents. Furthermore, the complexes remained soluble and stable in a 40:60 water:DMSO mixture. The Walphos complexes 13 and 15 rapidly precipitated under the same conditions. In line with this limited solubility 13 and 15 showed minimal cytotoxic effects when compared to their Josiphos counterparts 12 and 14 whose cytotoxic effects (in terms of IC50 values ) were six to seven times less than cisplatin. Reaction of the Walphos ligand and H[AuCl4] in a 1:1 ratio gave a dinuclear gold(I) complex 18 while the same reaction with Josiphos gave a mixture of intractable materials. However a 1:1 reaction of the Josiphos with AuCl(tht) gave a mononuclear three-coordinate gold(I) complex 16. A P^N chiral ligand comprising of a diphenylphosphine and a pyrazole moiety was also prepared and was complexed with AuCl(tht) to give a phosphine bound gold(I) complex 19. The structure of this complex was determined by X-ray studies. From the studies it became evident that apart from increasing the basicity of compound the pyrazolyl moiety remains dangling and the complex shows bond parameters similar to those observed with monophosphine ferrocenyl complexes. Chapter 4 reports on the bidentate and monodentate gold(III) complexes based on the (pyrazolylmethyl)pyridine ligands together with their platinum(II) complexes. The denticity of the complexes depended on the position of the pyrazolyl moiety relative to the pyridine nitrogen. When ortho-substituted ligands were reacted in a 1:1 ratio with H[AuCl4] in a mixture of water and ethanol at room temperature, bidentate cationic complexes of the general formula [AuCl2(PyCH2R2pz)][X], where R = Me (20), X = AuCl4-; R = Ph (21), X = Cl-; t-Bu (22), X= Cl- and p-tol (23), X = AuCl4-, were obtained. When para-substituted ligands were used under same reaction conditions, neutral monodentate complexes [AuCl3(PyCH2R2pz)], where R = Me (24) and R = Ph (25), were obtained. Platinum(II) complexes were obtained using K2[PtCl4] in a mixture of water and ethanol under reflux, and affords neutral complexes of the type [PtCl2(PyCH2R2pz)], where R = Me (27), Ph (28), t-Bu (29) and p-tol (30). When acetone was used instead of ethanol monoacetonylplatinum(II) complex (29a) was formed and on prolonged heating formation of the diacetonyl complex (28b) was observed. Both the platinum and the gold complexes were evaluated for their anti-cancer potency. The gold(III) complexes were devoid of any activity while the platinum complex 30 showed activity 8 times lower than cisplatin. The structures of 23, 25, 28, 29 and 29a were determined from single-crystal X-ray diffraction studies. In Chapter 5, tridentate complexes based on bis(pyrazolylethyl)amine are reported. These were prepared with the aim of improving water-solubility and cytotoxicity of the resulting complexes. New synthetic methods for preparation of the ligands NH(CH2CH2pz)2 (R = Me (L7), H (L8), t-Bu (L9)) under mild reaction conditions were developed albeit the yields obtained were generally low. The reaction of these ligands with H[AuCl4] gave corresponding tridentate dicationic gold(III) complexes [NH(CH2CH2pz)2][X]2 (R = Me (31), H (32), X = AuCl4 , and R = t-Bu (33), X = Cl-). Despite the ligands stabilizing the gold(III) ion, they showed no solubility in water. In an attempt to make the ligand system water soluble, a thiocarbamate analogue with pyrazolyl groups replaced by hydroxyl groups was prepared. However the resulting gold(III) complex [Au{CS2N(CH2CH2OH)2}2][AuCl2] (34) was found to be only soluble in DMSO.
506

The invisible power of the invisibles: A study of the efficacy of Narradrama method in assisting South African domestic workers in shifting their self-identity

Yarmarkov, Hanna January 2016 (has links)
Research report submitted to the Wits School of Arts University of the Witwatersrand, Faculty of Humanities In partial fulfillment of the requirements for the Degree of Master of Arts in the field of Drama therapy April 2016 / The aim of this research was to evaluate Narradrama as a drama therapy method in assisting South African domestic workers to shift their identity towards a more positive one, so they will be able to better deal with their current socially oppressive issues. I postulated, based on research done by sociologists and anthropologists, that domestic workers still feel oppressed marginalised and differentiated even to date, twenty years after the apartheid era; the racial discrimination that was perpetuated by the doctrine of the apartheid regime and cemented the master-servant relationship as the only possible relationship between domestic worker and employer was normalised within the harsh realities of minimum wages, long working hours and appalling living conditions; oppression of women by women, sexism and racism. Moreover, the domestic workers legal rights that were established after 1994 in the Bill of Rights have not changed their lives and working conditions. These working conditions continue to affect them and are a risk to their physical and mental health. (Mohutsioa-Makhudud, 1989; Williams, 2008; Ally, 2009). The risk that is inherent in chronic perceived discrimination to one’s mental health (Mohutsioa- Makhudu ,1989:40) and the risk of developing a negative identity and self hatred by internalising the negative views of a dominant society(Phinney, 1989:34) has influenced the decision to do this research. The method of Narradrama chosen for this study was researched by Dunne (as cited in Leveton 2010) and found to be effective in working with marginalised groups but has not yet been researched with a marginalised stratum within the South African context. Narradrama, became the preferred method as it is centred on story (Dunne and Rand, 2013:7) which led to the thought it would be effective when working with a group of African women who are considered to be story tellers in the African culture. (Scheub, 1970: 119-120). Thematic data analysis was used in analysing the results. Identity shift was measured by comparing the change between the initial negative themed stories, that substantiated the hypothesis that participants do feel oppressed and marginalised, with the new, positive themes that appeared later in the research processes The Narradrama processes were analysed through the theoretical lens of Landy’s role theory, who proposes that for a person to have a healthier identity he needs to take on a variety on new roles, and to be able to play them proficiently. The playing of new roles assists participants to enlarge their perspectives, discover new identity descriptions and experience what it would feel like to move forward in life in preferred ways towards a more manageable, hopeful future. (Landy, 1994:93-97) This parallels the Narradrama notion which claims that by re-storying a client’s narrative, the client opens up to new preferred choices; a new landscape of identity and action (Johnson and Emunah, 2009:182). The research results show the start of a shift, in the participants’ re-authored stories and their assumed choices of new roles- these changes signify that the group has benefited from processes. As the researcher, I therefore recommend that these processes be resumed in order to allow these identity shifts inclusive of the suggested roles to become more substantial, and more integrated in the participants’ identity within their current living and working context. However, though Narradrama proved to be a method that can assist this group, the results of this research cannot be generalised, and further research with different groups of domestic workers will need to be done in order to be able to generalise to the wider context of the stratum of South African domestic workers.
507

Building self-care practice through drama therapeutic techniques: a case study of the Zakheni Arts Therapy Foundation's wellbeing workshop

Spykerman, Nicolette January 2017 (has links)
A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Arts (Drama Therapy) March 2017 / The aim of this paper is to explore how Drama Therapeutic techniques can be used in self-care practice to reduce stress, burnout and compassion fatigue amongst community healthcare workers in South Africa. This is achieved by studying the case of the Zakheni Arts Therapy Foundation’s Wellbeing Workshop. The tools utilised by the Wellbeing Workshop are identified and explored to ascertain in what ways they can be useful in self-care practice. Semi-structured interviews are used to gain insight into the tools used most often and found to be most useful by both facilitators and participants in their personal self-care practice. The study shows that the care workers who participated in the Wellbeing Workshop did benefit from the training in that they gained an understanding of importance self-care and did begin to include some self-care practices into their daily routines. Participants did reflect that they found the dramatic tools useful but it is clear that care workers utilise the dramatic tools very differently than the facilitators. This raises questions about the relevance of how Drama Therapy is applied in the South African context as well as around whether drama tools are suitable tools for self-care practice amongst care workers in South Africa. / MT2018
508

O acompanhamento terapêutico na assistência e reabilitação psicossocial do portador de transtorno mental / Therapeutic continuity in health care and psychosocial rehabilitation of mental disorder patients

Carniel, Aline Cristina Dadalte 30 June 2008 (has links)
A reforma psiquiátrica possibilitou transformações na assistência à saúde mental e o acompanhamento terapêutico (AT), como modalidade de assistência e reabilitação psicossocial do portador de transtorno mental, faz parte dessas transformações. Desde então, o acompanhante terapêutico vem ampliando seus conceitos e fundamentando suas bases teóricas, sendo sua prática cada vez mais aceita por diferentes profissionais e valorizada por preencher as lacunas deixadas pelos tratamentos psiquiátricos tradicionais, principalmente depois que as portas dos manicômios, que enclausuravam o referido portador de transtorno mental e as maneiras adequadas de assisti-lo e reabilitá-lo, foram definitivamente abertas. O objetivo do presente estudo foi investigar a contribuição do AT no processo de assistência e reabilitação psicossocial de um portador de transtorno mental assistido em um Centro de Atenção Psicossocial e escolhido com a ajuda de sua equipe multiprofissional. Para isso, foram estabelecidos 16 encontros de AT, os quais foram desenvolvidos em diferentes locais, observados, e seus conteúdos registrados após cada encontro, sintetizados e analisados, segundo o método qualitativo. Os resultados mostraram contribuição muito positiva do AT na assistência e reabilitação psicossocial do portador de transtorno mental, tais como: resgate de sua autoestima; retomada de realização de atividades que fazia anteriormente ao início dos sintomas de seu transtorno mental; motivação para novamente buscar o lazer e conviver de forma mais saudável no seu meio familiar e social; criação de momentos de confronto de seu estado mental com a realidade, possibilitando modificações no comportamento e melhoria da qualidade de vida. Assim sendo, foi possível considerar que o AT constitui-se em mais uma modalidade terapêutica contribuindo para a assistência e reabilitação psicossocial do portador de transtorno mental e pode ser incluído nos planos terapêuticos dos serviços de assistência à saúde mental, pois se trata de modalidade terapêutica não tradicional, totalmente inserida no contexto da reforma psiquiátrica, que tem como princípio básico a mudança no foco da assistência aos portadores de transtornos mentais. / The psychiatric reform made it possible for transformations to take place in mental health care and therapeutic continuity (TC), as a health care modality and psychosocial rehabilitation of individuals with mental disorders. Since then, therapeutic continuity has broadened its concepts and founded its theoretical bases. Hence, its practice has become increasingly acknowledged by different professionals and valued for the fact it fills the gaps that were left from traditional psychiatric treatments, mainly after the doors to asylums, which used to keep mentally ill individuals cloistered, were completely open and appropriate forms of looking after these patients and rehabilitate them were implemented. The purpose of the present study was to investigate the contribution of TC over the health care process and psychosocial rehabilitation of an individual with mental disorders seen at a Psychosocial Care Center, and chosen with the help of its multiprofessional team. To do this, 16 TC appointments were scheduled, which were carried out at different locations. These meetings were observed and their contents were recorded, summarized, and analyzed according to the qualitative method. The results showed that TC has a very positive contribution in the health care and psychosocial rehabilitation of mental disorder patients, with actions such as: recovering selfesteem, going back to activities the patient did before his mental disorder symptoms appeared, motivation to once again become involved in leisure activities and lead a healthier life among his family and social environment, creating moments of confrontation between his mental condition and reality, which made it possible to change his behavior and improve his quality of life. Thus, it is understood that TC is another therapeutic modality that contributes with the psychosocial rehabilitation of patients with mental disorders. Furthermore, it can be included in the therapeutic plans of mental health care services, since it is a untraditional therapeutic modality totally inserted in the context of psychiatric reform, whose main principle is to change the focus of health care services to individuals with mental disorders.
509

Effects of Chinese medicine on endothelial dysfunction: studies on acupuncture and herbal medicine / CUHK electronic theses & dissertations collection

January 2014 (has links)
Endothelial dysfunction (ED) is associated with many cardiovascular conditions including hypertension and hyperhomocysteinemia. The decreased bioavailability of nitric oxide and increased oxidative stress are the hallmarks of ED. Apart from the mainstream Western medicine treatment, Chinese medical interventions have also demonstrated their capacity in dealing with a great variety of cardiovascular conditions. The effectiveness of acupuncture on hypertension has been recognized by the World Health Organization but the underlying mechanisms have hitherto remained largely obscure. A commonly prescribed Chinese herb, the Root of Rhodiola rosea has been used to treatment a wide range of cardiovascular conditions but its effect on ED is also unclear. In this thesis, we have explored the effects and the underlying mechanism of these two important Chinese medical interventions. / In the first part, we have performed an acupuncture study on hypertensive animals. Eighteen weeks old adult Wistor Kyoto Rats (WKYs) and Spontaneously Hypertensive Rats (SHRs) were divided into WKY control, SHR control, Sham-acupuncture and real acupuncture groups. Electroacupuncture was performed on acupoints ST36 and LR3 in the real acupuncture group for 6 weeks. The blood pressure at the end of the treatment was lowered in acupuncture group when compared with SHR control and sham-acupuncture group. Serum angiotensin II level in SHR controls was higher than that in WKY control and acupuncture treatment significantly attenuated it. Dihydroethidium (DHE) imaging showed that the reactive oxygen species (ROS) level was reduced in the aortas and carotid arteries of acupuncture treated SHR. Biochemical assays showed that acupuncture inhibited the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and enhanced antioxidant capacity. In functional studies, the endothelial dependent relaxation of aorta rings and carotid arteries to acetylcholine were improved in acupuncture group. SHRs received acupuncture also expressed a elevation of eNOS and peNOS level and inhibition of nitrotyrosine level in Western blotting assay. The nitrate/nitrite level in aortic tissue was also increased by acupuncture. The findings concluded that one of the possible mechanisms of acupuncture in lowering blood pressure involved the improvement of oxidative stress, nitric oxide bioavailability and endothelium functions. / In the second part, we have studied the effects of salidroside, an active ingredient of the root of Rhodiola rosea with documented antioxidative, antihypoxia and neuroprotective properties on homocysteine induced ED. Functional studies on the rat aortas were performed to delineate the vascular effect of salidroside. Exposure to homocysteine attenuated endothelium-dependent relaxations in rat aortas while salidroside pretreatment rescued it. DHE imaging revealed that salidroside inhibited homocysteine-induced elevation in ROS production in both aortas and cultured endothelial cells. Western blot analysis showed that salidroside increased the phosphorylation of eNOS which was diminished by homocysteine in endothelial cells. Moreover, salidroside inhibited the NOX2 expression which was promoted by homocysteine in aorta tissue. The findings suggested that salidroside was effective in preserving the NO bioavailability and reducing ROS level, thereby protecting against homocysteine-induced impairment of ED. / We have successfully demonstrated the two Chinese medicine modalities, i.e. acupuncture and salidroside, a naturally occurring chemical compound isolated from Rhodiola rosea, delivered beneficial effects on ED, and both of them exert anti-oxidative effects for their action. Our experimental findings have enhanced the prospective of using Chinese medical interventions to manage oxidative stress-associated cardiovascular conditions and also helped put the clinical use of Chinese medical interventions on a more scientific footing. / 內皮功能失調與很多心血管系統疾病,包括高血壓和高半胱氨酸過高症有著十分密切的關系,一氧化氮供應減少與氧化應激增加均為這病理現象的一個特徵。除了主流的西方醫學治療方法外,中醫藥也一直表現出對各種心血管系統疾病有著明顯的療效。其中以針灸治療高血壓雖然己被世界衛生組織認可為一有效之療法,然而其療效原理卻並未被完全了解。另外,中草藥當中的紅景天,其對心血管疾病的療效亦非常顯著,唯其對內皮功能失調之影響卻仍有待查証。在這部論文當中,作者將會對以上兩項中醫藥治療方法的原理作出深入探討。 / 在第一部份的實驗當中,作者對自發性高血壓的大鼠施行了針灸治療。把十八週歲的自發性高血壓大鼠與京都種大鼠分為1)京都種大鼠對照組 2)自發性高血壓大鼠對照組 3)假針組針針刺組。針刺組中所使用的方案乃於足三里和太沖施行為期六週的電針治療。治療後針刺組的血壓相對於高血壓大鼠對照組和假針組均有明顯下降。同時針刺組大鼠血液中的血管緊張素II亦明顯降低。顯微鏡螢光造影發現於主動脈與頸動脈組織中,超氧化因子數量於針刺後均低於另外兩組高血壓大鼠對照組與假針組。另外實驗結果亦發現尼克酰胺腺嘌呤二核苷酸磷酸氧化酶的活動於針刺後下降,而抗氧化總容量則有所提升。另一方面,血管功能測試則顯示在針刺組內,由乙酰胆碱所引發的血管舒張比對照所產生的有所增加。而內皮一氧化氮酶和磷化皮內皮一氧化氮酶於血管中的表達則於針刺治療後有所增加,反觀硝基酪氨酸的含量則於針刺後減少。針刺對於血管組織中的亚硝酸盐/硝酸盐含量均有刺激作用。綜合而言,針刺能透過抑制氧化應激從而增加血管中一氧化氮的含量,最後達至內皮功能改善而降低血壓。 / 在第二部份,作者對中藥紅景天內其中一種活性成份紅景天苷對半胱氨酸所引起的內皮功能損傷進行研究。血管功能測試顯示半胱氨酸抑制了由乙酰胆碱所引發的血管舒張,而紅景天苷則能有效逆轉該抑制作用。顯微鏡螢光造影則發現紅景天苷能壓制由半胱氨酸所刺激的超氧化因子,另一方面能增加由半胱氨酸所抑制的磷化皮內皮一氧化氮酶的表達。尼克酰胺腺嘌呤二核苷酸磷酸氧化酶為超氧化因子的其中一個主要來源,半胱氨酸被發現會對其當中NOX2亞組的表達有刺激作用,而紅景天苷則能減少其表達。實驗結果顯示紅景天苷對半胱氨酸所引起的內皮功能損傷有顯著保護作用,其原理則與減少氧化因子從而增加一氧化氮的含量有密切關系。 / 整體而言,本論文成功顯示針灸與紅景天苷兩項中醫藥治療方案均能夠透過抑制超氧化因子而改善內皮功能捐傷。實驗結果加強了中醫藥於治療氧化應激相關的心血管疾病的應用,為中醫藥發展提供堅實的科學基礎。 / Leung, Sin Bond. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2014. / Includes bibliographical references. / Abstracts also in Chinese. / Title from PDF title page (viewed on 01, November, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
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Actions of tumour necrosis factor: in vitro cytotoxicity and in vivo toxicity.

January 1988 (has links)
by Wong Wah Yau. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 219-228.

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