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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.
41

Isoleringsrutiner gällande livsmedelsbegränsningar för patienter på sjukhus där allogena stamcellstransplantationer genomförs

Sjögren, Erik, Haraldsson, Nellie January 2017 (has links)
Bakgrund: Stamcellstransplantation är en behandlingsmetod mot flera olika typer av leukemi. Efter transplantationen blir patienten infektionskänslig. Vid detta tillstånd skyddsisoleras patienten och får en livsmedelsbegränsad kost.Syfte: Sammanställa och jämföra isoleringsrutiner gällande livsmedelsbegränsningar för patienter vid Sveriges hematoloigavdelningar där allogen transplantation sker och jämföra med aktuell forskning bakom livsmedelsbegränsningar.Metod: Tvärsnittsstudie vid jämförelsen av livsmedelsbegränsningarna vid Sveriges hematologiavdelningar samt en litteraturstudie vid undersökningen av aktuell forskning i databaserna Pubmed och Cinahl.Resultat: I tvärsnittsstudien använde alla sjukhusen olika rutiner. Ingen signifikant skillnad gällande infektionsincidensen mellan patienter som hade livsmedelsbegränsningar jämfört med de som inte hade det fanns i litteratursökningen.Slutsats: Livsmedelsbegränsningar minskar troligtvis inte infektionsrisken för infektionskänsliga patienter. Det behövs högkvalitativ forskning för att utforma tydliga riktlinjer kring vilka livsmedelsbegränsningar som bör användas. / Background: Stem cell transplantation is a treatment for patients with leukemia. After the transplantation, the patients are at a higher risk of getting an infection and are therefore kept in protective isolation and get a food restricted diet.Purpose: To compile and compare the differences in food restricted diet for neutropenic patients at the hematology departments in Sweden where stem cell transplantation is performed and compare food restricted diet to current research.Method: A cross-sectional study to compare the food restrictions and a literature study to find out what the current research says using Pubmed and Cinahl.Result: The cross-sectional study showed that all the hospitals used different diets. In the literature review, no significant difference regarding infections rates when comparing patients who ate a food restricted diet with those who did not.Conclusion: Food restrictions are unlikely to reduce the infection rate of neutropenic patients. More high quality research is needed to formulate clear guidelines about what food restricted diet should be used.
42

Verträglichkeit und Effektivität Cyclosporin A-vermittelter Immunsuppression beim Schaf für die xenogene, intrazerebrale Transplantation

Diehl, Rita 28 November 2016 (has links) (PDF)
Einleitung Der Einsatz von Stammzellen als Grundlage neuer therapeutischer Strategien wird bereits seit über 25 Jahren intensiv erforscht. Stammzellen sind in der Lage, in verschiedene funktionale Zelltypen auszudifferenzieren und verfügen über ein enormes Proliferationspotential (NAM et al. 2015). Ausgehend von den Fähigkeiten von Stammzellen sehen Forscher und Kliniker erstmals eine realistische Möglichkeit, kurative Therapieoptionen für Erkrankungen zu entwickeln, die bisher als schwer behandelbar oder sogar unheilbar angesehen wurden. Davon könnten insbesondere Patienten chronisch-degenerativer neurologischer und zerebrovaskulärer Erkrankungen, einschließlich der großen Anzahl an Schlaganfallopfern, profitieren. Schlaganfälle repräsentieren eine der häufigsten Todesursachen in der westlichen Welt (LOPEZ et al. 2006). Ein Drittel der betroffenen Patienten verstirbt innerhalb eines Jahres, während etwa 40% von dauerhaften Behinderungen betroffen sind (MOZAFFARIAN et al. 2015). Trotz intensiver Forschung existieren neben der systemischen Thrombolyse, die auf einen engen Zeitraum von maximal 4,5 Stunden nach dem Akutereignis beschränkt ist, keine zugelassenen Therapieoptionen (HACKE et al. 2008, SAVER et al. 2009). Zelltherapeutische Strategien zur Behandlung des Schlaganfalls werden daher als besonders vielversprechend angesehen (ANDRES et al. 2011). Neben den bereits gesicherten Erkenntnissen zur stammzelltherapeutischen Sicherheit und Wirksamkeit aus Studien unter Einsatz gängiger Nagermodellen (BLISS et al. 2006, JOO et al. 2013) wird insbesondere die Überprüfung der Wirksamkeit an geeigneten Großtiermodellen gefordert, die die Situation des menschlichen Schlaganfallpatienten möglichst realistisch wiedergeben sollen (SAVITZ et al. 2011). Eine Voraussetzung für die erfolgreiche Testung eines zelltherapeutischen Ansatzes in einem Großtiermodell mit fokaler zerebraler Ischämie besteht darin, ein langfristiges Überleben xenogener Zelltransplantate durch ein geeignetes Immunsuppressionsprotokoll zu erreichen. Die Notwendigkeit einer Immunsuppression besteht darin, dass sowohl allo- als auch xenogene Transplantate eine Immunantwort beim Empfänger auslösen und somit zu einer Abstoßungsreaktion führen können (JANEWAY 2002). Die Anwendung von immunsuppressiven Medikamenten geht dabei aber häufig mit Nebenwirkungen einher. Insbesondere beim Schaf existiert jedoch nur eine limitierte Datenlage zu immunsuppressiven Protokollen und deren Nebenwirkungen. Ziele der Untersuchung Das Ziel der vorliegenden Studie bestand darin, eine xenogene Transplantation von fetalen humanen neuralen Progenitorzellen (fhNPZ) in einem gesunden Schafsmodell durchzuführen, um die Wirksamkeit in Hinblick auf das Transplantatüberleben und die Nebenwirkungen einer Immunsuppression mittels Cyclosporin A (CsA) zu untersuchen. Materialien und Methoden Hierfür wurden je 5 Schafe in zwei Gruppen über einen Zeitraum von 64 Tagen immunsupprimiert (iCsA: 3 mg CsA/kg 2x tägl. bis einschließlich Tag 36, danach 3 mg CsA/kg 1x tägl. jeden 3. Tag; kCsA: kontinuierlich 3 mg CsA/kg 2x tägl.), während eine Kontrollgruppe (Kon) von ebenfalls 5 Tieren keine Immunsuppression erhielt. Am Versuchstag 22 wurde den Schafen eisenmarkierte fhNPZ (Eisenkonzentration: 3,0 mM, ca. 200.000 Zellen pro Transplantationsposition) stereotaktisch in das gesunde Gehirn transplantiert. Aufgrund der Eisenmarkierung der Stammzellen konnten diese an den Versuchstagen 23, 36 und 64 mittels 3,0 MRT-Aufnahmen in vivo überwacht und anschließend ex vivo das Überleben der fhNPZ im Schafhirn 42 Tage nach Transplantation histologisch untersucht werden. Für die Untersuchungen zu Wirkspiegeln und Nebenwirkungen von CsA im Schaf wurden den Versuchstieren innerhalb des Versuchszeitraums regelmäßig Blutproben entnommen und am Versuchsende eine pathologische und histologische Untersuchung von Leber und Nieren durchgeführt. Ergebnisse Bei den durchgeführten Untersuchungen konnte festgestellt werden, dass die CsA-Wirkspiegel im Blut bei der kCsA (424,0 ± 135,0 ng/ml) signifikant höher waren im Vergleich zur iCsA (198,5 ± 155,9 ng/ml). Diese Unterschiede besaßen jedoch keinen Einfluss auf das Langzeitüberleben der transplantierten fhNPZ. In keiner der drei Versuchsgruppen konnten vitale Zellen 42 Tage nach der Transplantation aufgefunden werden. Die Untersuchung der Nebenwirkungen von CsA ergab, dass die Langzeitgabe von CsA Anzeichen für einen hämatologischen Einfluss zeigt. Ebenso konnte sowohl eine hepatotoxische, als auch eine nephrotoxische Wirkung von CsA beim Schaf nachgewiesen werden. Schlussfolgerungen Schlussfolgernd kann zusammengefasst werden, dass die Gabe von 3 mg CsA/kg 2x tägl. nicht suffizient einer Abstoßungsreaktion xenogener ins Schafhirn transplantierter fhNPZ entgegenwirkt. Für das Ziel einer suffizienten zelltherapeutischen Anwendung im Schaf nach einem Schlaganfall sind somit weitere Untersuchungen zu einer wirksamen Immunsuppression beim Schaf und zu einem verbesserten Transplantatüberleben notwendig. Desweiteren konnten klinische und pathologische Nebenwirkungen beim Schaf durch die Langzeitgabe des Immunsuppressivums CsA festgestellt werden.
43

Patienters upplevelse av att genomgå en stamcellstransplantation : En litteraturstudie

Persson, Linnea, Stenow, Maria January 2016 (has links)
Bakgrund: Varje år genomförs mer är 50 000 stamcellstransplantationer världen över och antalet ökar. Stamcellstransplantation, är en potentiell terapeutisk behandling för ett flertal olika livshotande blodsjukdomar. Återhämtningen efter behandlingen är lång, genomsnittstiden är ett år innan patienterna är tillbaka till samma livskvalitet de hade innan. Syfte: Syftet med litteraturstudien var att beskriva patienters upplevelse av att genomgå en stamcellstransplantation Metod: En litteraturstudie baserad på 1o kvalitativa studier. Resultat: Resultatet presenterades i fyra kategorier och sammanlagt tolv subkategorier. Att livet hotas innebar osäkerheter och rädslor. Alternativa hanteringsstrategier som användes var optimism, att skjuta ifrån sig, tro på något större, förlita sig på andra och att bli expert på sin sjukdom. Konsekvenser av behandlingen var kroppsligt lidande och att vara nära döden. Nystart innebar en ny tillvaro, förändrad syn på livet och förändrade relationer. Konklusion: Upplevelsen av behandlingen varierar mellan varje patient och osäkerhet och rädslor inför vad som kommer att hända fanns. Hopp gavs av anhöriga och vårdpersonal. För att hantera situationen använde de sig av olika strategier. Bristfällig information bidrog till patienternas osäkerhet och behov av bättre individuellt anpassad information finns. Nyckelord: Livskvalitet, patienters upplevelse, stamcellstransplantation / Title: Patients' experience of undergoing stem cell transplantation. Background: Every year more than 50 000 stem cell transplantations are performed worldwide. Stem cell transplantation is a potential therapeutic treatment for several life-threatening blood diseases. The recovery after treatment is long, the average time is one year before the patients are back to the same quality of life as they had before treatment started. Aim: The aim of this study was to describe patients' experience of undergoing stem cell transplantation. Methods: A literature study based on 10 qualitative articles. Results: The results were presented in four categories and twelve subcategories. Threat on life included both insecurity and fears. Alternative coping strategies used were optimism, distance yourself, believe in something bigger, relying on others and becoming expert on your disease. Consequences of the treatment included bodily suffering and being close to death. The new beginning included a new existence, a changed outlook on life and changed relationships. Conclusion: The experience of the treatment differed between patients and there was uncertainty and fears about what was going to happen. Relatives and health professionals gave hope to the patients. Different coping strategies were used to cope with the situation. Inadequate information contributed to the uncertainty among the patients and there is a need for better individualized information. Keywords: Quality of life, patients experience, stem cell transplantation
44

Neutropenia febril em coorte de adultos submetidos ao transplante de células-tronco hematopoiéticas / Febrile neutropenia in a cohort of adults submitted to hematopoietic stem cell transplantation.

Kuwano, Mayumi Araujo 07 August 2018 (has links)
Introdução: A neutropenia febril (NF) é um evento adverso intrínseco ao transplante de células-tronco hematopoiéticas (TCTH), decorrente da mielossupressão ocasionada pelo procedimento, que impacta de modo importante na morbidade e na mortalidade do paciente. Objetivos: Analisar os pacientes submetidos ao TCTH quanto a ocorrência de NF. Método: Coorte retrospectiva conduzida com 61 pacientes submetidos ao TCTH no Hospital de Clínicas da Universidade Estadual de Campinas. Foram extraídos dados relativos a características basais dos pacientes, procedimento de TCTH, tempo de internação e desfecho clínico para determinar os fatores associados à NF. As variáveis independentes foram idade, sexo, comorbidades, diagnóstico, tipo de transplante, regime de condicionamento, fonte das células, nº de CD34, tempo de enxertia, escore de risco pré-TCTH do EBMT, SAPSII. A NF foi definida de acordo com o Common Terminology Criteria for Adverse Events (CTC/AE) v4.0, considerando o desfecho dicotômico, a duração em dias, a data da ocorrência, o grau e a análise de sobrevida. Os dados foram analisados por meio de testes paramétricos e não paramétricos, dependendo do nível de mensuração das variáveis e utilizaram-se Kaplan-Meier e regressão logística. Para todas as análises considerou-se nível de significância de 5%. Resultados: A incidência de NF nos pacientes submetidos ao TCTH foi de 78,7%, com duração média de 8,3 dias, sem diferença significativa entre os tipos de transplantes (p=0,176). Não foram encontrados fatores de risco para a NF, porém, os pacientes submetidos ao transplante autólogo (p=0,022) e ao regime de condicionamento mieloablativo (p=0,026) apresentaram menor sobrevida para este evento adverso. Os pacientes que utilizaram ventilação mecânica (p=0,052), que necessitaram do uso de drogas vasoativas (p=0,012) e que foram a óbito (OR=9,66; p=0,052), apresentaram NF em sua totalidade. Conclusão: A incidência de NF foi expressiva e, ainda que não tenham sido identificados fatores associados a ela, os pacientes submetidos ao regime NMA e TCTH alogênico apresentaram maior sobrevida para o surgimento de NF. Estes achados relativos a sobrevida podem subsidiar o enfermeiro na proposição de intervenções, visando evitar complicações infecciosas decorrentes da NF. / Introduction: Febrile neutropenia (FN) is an intrinsic adverse event to hematopoietic stem cell transplantation (HSCT), due to the myelosuppression caused by the procedure, which has an important impact on patient morbidity and mortality. Objectives: To analyze the patients submitted to HSCT regarding the occurrence of FN. Method: Retrospective cohort with 61 patients submitted to HSCT at Hospital de Clínicas, State University of Campinas. Data were extracted on the baseline information of patients, HSCT procedure, time of hospitalization and clinical outcome to determine the factors associated with FN. The independent variables were age, gender, comorbidities, diagnosis, type of transplantation, conditioning regime, cell source, CD34 number, grafting time, pre-HSCT risk score of EBMT, SAPSII. The FN was defined according to the Common Terminology Criteria for Adverse Events (CTC / AE) v4.0, considering the dichotomous outcome, duration in days, date of occurrence, degree and survival analysis. Data were analyzed using parametric and non-parametric tests, depending on the level of measurement of the variables and Kaplan-Meier and logistic regression were used. A significance level of 5% was considered for all analyzes. Results: The incidence of FN in patients submitted to HSCT was 78.7%, with an average duration of 8.3 days, with no significant difference between the types of transplants (p = 0.176). No risk factors were found for FN, however, patients submitted to autologous transplantation (p = 0.022) and myeloablative conditioning (p = 0.026) presented lower survival rates for this adverse event. Patients who used mechanical ventilation (p = 0.052), who required the use of vasoactive drugs (p = 0.012) and who died (OR = 9.66, p = 0.052) presented FN in their entirety. In addition, the occurrence of FN had an association with longer hospitalization time (p = 0.003). Conclusion: The incidence of FN was significant. Although no associated factors were identified, patients submitted to NMA and allogeneic HSCT presented a higher survival rate for the onset of FN. These findings regarding survival can subsidize the nurse in proposing interventions, in order to avoid infectious complications due to FN.
45

Cuidados de enfermagem prestados a pacientes onco-hematólogos submetidos a altas doses de quimioterapia / Nursing care towards onco-haematological patients to undergo high doses of chemotherapy.

Carlucci, Viviane Dias da Silva 19 September 2012 (has links)
Os pacientes onco-hematológicos submetidos a altas doses de quimioterapia sejam para tratamento de suas doenças de base ou para realização do transplante de células-tronco hematopoéticas (TCTH) sofrem com diversos efeitos adversos. Entre esses efeitos estão a neutropenia febril, mucosite, distúrbios do sono, depressão, ansiedade, fadiga física e mental e diminuição da capacidade do estado funcional do paciente. Neste contexto, a equipe de enfermagem tem papel fundamental na avaliação e implementação dos cuidados específicos para essa clientela. Trata-se de uma revisão integrativa da literatura cujo objetivo foi identificar, avaliar e sintetizar o conhecimento relacionado aos cuidados de enfermagem prestados aos pacientes onco-hematológicos adultos submetidos a altas doses de quimioterapia seguida ou não do TCTH. As bases de dados Pubmed/ Medline, Cinahl, Lilacs e Biblioteca Cochrane foram selecionadas para a busca dos estudos primários indexados, nos últimos 10 anos. Os descritores controlados foram delimitados para cada uma das bases de dados. Dos 725 estudos localizados e considerando os critérios seleção adotados, 45 estudos foram selecionados para leitura na íntegra e 13 estudos primários foram incluídos na revisão integrativa. Para extração dos dados foi utilizado um instrumento validado. A análise dos dados foi descritiva. Os estudos primários incluídos foram divididos nas seguintes categorias temáticas: fadiga e atividade física, segurança do paciente e cuidados com mucosite. De acordo com os estudos primários avaliados pode-se observar que as intervenções propostas para o cuidado dos pacientes submetidos a altas doses de quimioterapia seguidos ou não ao TCTH foram, em sua maioria, para minimizar ou promover a diminuição dos efeitos adversos relacionados ao tratamento. Os efeitos adversos apresentados causam ao paciente prejuízo no estado funcional, nutricional, na qualidade de sono e repouso, qualidade de vida. Cabe ao enfermeiro implementar um conjunto de estratégias para ter um controle da situação atual do paciente para poder intervir no momento necessário adequado, a fim de evitar complicações. / Onco-haematological patients to undergo high doses of chemotherapy for disease treatment as well for hematopoietic stem cell transplantation (TCTH) suffer with adverse side effects. Among these effects are febrile neutropenia, mucositis, sleep disorder, depression, anxiety, physical and mental tiredness and decrease of the patient\'s functional capacity. In this text, the nurse team has important role over the assessment and implementation of specific care towards these kinds of patients. Referring to integrative literature review which purpose is identify, assess and summarize the understandings related to nursing care towards adult onco- haematological patients who underwent high doses of chemotherapy followed or not to TCTH. Data base Pubmed/ Medline, Cinahl, Lilacs and Cochrane Library have been selected to search the indicated primary studies over the past 10 years. The controlled describers have been delimited for each of data base. From over the 725 found studies and considering the defined rules, 45 studies have been selected for full reading and 13 primary studies have been included over the integrative review. For data pull out it was used a validated mechanism. Data analysis was descriptive. The primary studies have been divided into the following categories: tiredness and physical activity, patient safety and mucositis care. According to the assessed primary studies it can be noticed that the offered intervention for patient\'s care that underwent to high doses of chemotherapy followed or not to TCTH were, in majority, to minimize or promote the decrease of the adverse side effects related to the treatment. The presented side effects caused damage to the patient functional condition, nutritional condition, sleep quality and rest, quality of life. The nurse is in charge of implementing a strategy to obtain the control of the current situation of the patient in order to interfere at the adequate moment to avoid any complications.
46

Enxaguatório bucal de chamomilla recutita (camomila): preparo e aplicação na mucosite bucal / Mouthwash with Chamomilla recutita (chamomile): preparation and use in oral mucositis

Braga, Fernanda Titareli Merizio Martins 04 July 2011 (has links)
A mucosite bucal (MB) é uma complicação inflamatória frequente manifestada pelos pacientes submetidos ao transplante de células-tronco hematopoéticas (TCTH), em decorrência do agressivo regime terapêutico empregado. Entretanto, sua prevenção e tratamento ainda são controversos na literatura. A Chamomilla recutita tem sido utilizada com propósitos terapêuticos há séculos, e alguns centros de TCTH a empregam tanto para a prevenção como para o tratamento da MB. Contudo, não se identificaram estudos que investigassem sua ação nessa clientela. Assim, o presente estudo tem por finalidade comparar a incidência, intensidade e os dias de mucosite bucal de pacientes adultos submetidos ao TCTH segundo as doses (0,5; 1 ou 2%) de Chamomilla recutita em enxaguatório bucal. Para tanto, este estudo foi conduzido em quatro etapas. Primeiramente, realizou-se revisão integrativa da literatura, com o intuito de identificar as evidências científicas disponíveis, em relação ao uso da Chamomilla recutita para redução da ocorrência e intensidade de processos inflamatórios. Evidenciou-se que a Chamomilla recutita possui provável ação antiinflamatória tópica, para diversas alterações inflamatórias. Considerando os resultados desta revisão e os obtidos nos estudos in vitro e em animais, julgou-se oportuno desenvolver o estudo clínico. Na segunda etapa, procedeu-se à seleção da droga vegetal, análise físicoquímica, microbiológica e à quantificação da apigenina-7-glucosídeo. Os testes realizados identificaram a excelente qualidade dos capítulos florais da amostra selecionada. Em seguida, na terceira fase, obteve-se o extrato fluido, cujas análises evidenciaram a manutenção da qualidade e do teor do princípio ativo. Posteriormente, incorporou-se o extrato com sucesso em três formulações de enxaguatório bucal, de acordo com as dosagens propostas para o estudo clínico (0,5; 1 e 2%). Finalmente, foi realizado o estudo clínico com 23 pacientes submetidos ao TCTH alogênico, randomizados em quatro grupos. Em relação à incidência de mucosite 5 (83,3%) pacientes do grupo B que receberam o enxaguatório com Chamomilla recutita, na dose de 1%, não apresentaram manifestações da mucosite bucal, enquanto 4 (80%) pacientes do grupo D (controle) apresentaram manifestações da MB. Destaca-se também que no grupo C, 3 (50%) pacientes não manifestaram MB. Quanto à intensidade, nenhum grupo apresentou o grau máximo (IV). Contudo, 66,6% dos pacientes do grupo A, 16,7% do B, 50% do C e 60% do D apresentaram mucosite graus II e III. Em relação ao sabor, aroma e cor a maioria dos pacientes os classificaram como sendo muito agradável ou agradável. A náusea foi a única manifestação relatada por dois pacientes durante a realização do bochecho. Dessa forma, os resultados evidenciaram uma possível ação do enxaguatório contendo Chamomilla recutita na redução da incidência da mucosite, na dose de 1%, em pacientes submetidos ao TCTH, bem como uma menor intensidade de mucosite graus II e III nos grupos que receberam as doses de 1 e 2%. Contudo, para confirmar estes achados faz-se necessário ampliar a amostra deste estudo empregando o método aqui desenvolvido. O enxaguatório bucal de Chamomilla recutita nas dosagens de 0,5; 1 e 2% foi bem tolerado pelos pacientes e demonstrou ser seguro, uma vez que nenhum efeito adverso moderado ou severo foi identificado. / Oral mucositis (OM) is an inflammatory complication frequently manifested by patients undergoing Hematopoietic Stem Cell Transplantation (HSCT), as a result of aggressive treatment regimen employed. However, prevention and treatment are still controversial in literature. Chamomile has been used for therapeutic purposes for centuries and has been employed in some HSCT services for both prevention and treatment of OM. However, no studies that investigate its action in this clientele have been identified. Thus, this study aimed to compare the incidence, intensity and duration of oral mucositis in adult patients undergoing HSCT according to the doses (0.5; 1 or 2%) of Chamomilla recutita in mouthwash. The study was carried out in four stages. First an integrative literature review was conducted, in order to identify the scientific evidence available regarding the use of Chamomilla recutita to reduce the occurrence and intensity of inflammatory processes. It was evidenced that Chamomilla recutita is likely to have topic anti-inflammatory action, for several inflammatory disorders. Considering the results of this review and those obtained with studies in vitro and in animals, it was deemed appropriate to develop the clinical study. At the second stage, the plant drug was selected, physical-chemical and microbiological analysis were carried out and quantification of apigenin-7-glucoside was determined. Tests identified the excellent quality of capitula from the selected sample. In sequence, at the third phase, the fluid extract was obtained, whose analysis showed the maintenance of quality and content of active principle. Subsequently, the extract was successfully incorporated in three formulations of mouthwash, according to the dosages proposed for the clinical study (0.5; 1 and 2%). At last, a clinical study with 23 patients who underwent allogeneic HSCT was performed, randomized into four groups. Regarding the incidence of mucositis, 5 (83.3%) patients in group B who received the mouthwash with Chamomilla recutita, at the 1% dose, did not show manifestations of oral mucositis, while 4 (80%) patients in group D (control) presented signs of oral mucositis. It is highlighted that in group C 3 (50%) patients did not present mucositis. As for intensity, no group showed the highest degree (IV). However, 66.6% of patients in group A, 16.7% in B, 50% of C and 60% of D had mucositis grades II and III. Regarding the taste, flavor and color, most patients rated them as being very pleasant or pleasant. Nausea was the only manifestation reported by patients during the course of mouthwash, registered by 1 (25%) patient in group B and 1 (16.7%) in group C. Thus, results evidenced a possible action of the mouthwash containing Chamomilla recutita in reducing the incidence of mucositis at a dose of 1% in HSCT patients, as well as a lower intensity of mucositis grades II and III in groups that received 1 and 2% doses. However, to confirm these findings it is necessary to enlarge the sample using the method developed by this study. The mouthwash with Chamomilla recutita in dosages of 0.5; 1 and 2% was well tolerated by patients and demonstrated to be safe, since no moderate or severe adverse effect was identified.
47

Tenogenic differentiation of tendon derived stem cells (TDSCs) and application for tendon repair. / CUHK electronic theses & dissertations collection

January 2012 (has links)
肌腱損傷發生率高,並且癒合結果很不理想,因為少量的肌腱細胞缺乏有效的修復能力,僅僅通過瘢痕形成來癒合, 肌腱瘢痕癒合難以恢復原本的肌腱組織結構及力學特性。目前,國內外臨床上治療肌腱損傷的方法很多,包括藥物、物理治療、手術等,這些並不能獲得滿意的療效。因此,如何採用肌腱組織工程技術迅速、安全、有效的修復肌腱損傷已成為運動醫學領域急需解決的重要問題。 / 有研究表明,骨髓間充質幹細胞、表皮成纖維細胞、肌腱細胞和胚胎幹細胞通過肌腱組織工程技術用於肌腱修復及再生取得了不錯的療效。但是,這些來源的細胞存在分化效率低,形成畸胎瘤和異位骨化等風險。近來,有研究報導可從人、小鼠、大鼠和兔的肌腱組織中分離培養出幹細胞,可作為肌腱組織工程種子細胞的一種新選擇,用於肌腱修復和再生。對於間充質幹細胞的成肌腱分化,有研究報導結締組織生長因子(CTGF)和抗壞血酸(維生素C的一種形式)在膠原及細胞外基質合成、調節細胞成肌腱分化方面扮演者重要的角色。 / 本研究的旨在:(1)在大鼠髕腱損傷模型中,證實肌腱幹細胞可作為一種新的幹細胞來源用於肌腱修復;(2)檢驗結締組織生長因子和抗壞血酸能在體外促進肌腱幹細胞的成肌腱分化;(3)嘗試通過肌腱幹細胞的成肌腱分化過程在體外構建不含外源性支架的肌腱樣組織;(4)探索該肌腱樣組織在大鼠髕腱損傷模型中是否可以促進肌腱癒合。 / 在大鼠急性髕腱損傷動物模型中,與對照組相比,肌腱幹細胞組具有更好的膠原排列,顯著增高的最大張力和楊氏模量,表明肌腱幹細胞可作為一種新的幹細胞來源用於肌腱損傷的修復。結締組織生長因子和抗壞血酸體外誘導肌腱幹細胞2周後,可顯著增加Tenomodulin, Scleraxis, Thbs4, I型膠原等肌腱相關基因的表達以及膠原蛋白的合成,說明結締組織生長因子和抗壞血酸可促進肌腱幹細胞的成肌腱分化。被結締組織生長因子和抗壞血酸誘導兩周後,肌腱幹細胞可形成了細胞膜樣結構,將這種細胞膜纏繞在迴紋針上,構建成肌腱樣組織,其具有相對疏鬆的細胞外基質和雜亂排列其中的肌腱幹細胞,以及表達Tenomodulin,I型膠原和III型膠原。將該肌腱樣組織移植到裸鼠體內8周和12周可形成新生肌腱組織,梭形細胞縱行分佈在平行的膠原纖維之間,並表達Tenomodulin,I型膠原和III型膠原蛋白。在大鼠髕腱損傷動物模型中,與對照組相比較,該肌腱樣組織可通過恢復肌腱組織結構及生物力學特性來促進肌腱癒合。 / 總的來說,本研究證實肌腱幹細胞可作為一種新的幹細胞來源用於肌腱組織工程促進肌腱再生。結締組織生長因子和抗壞血酸可調控肌腱幹細胞的成肌腱分化,並形成細胞膜結構。該細胞膜結構可在體外構建出不含外源性支架的肌腱樣組織,進而在裸鼠體內形成新生肌腱,並且在大鼠髕腱損傷模型中可有效的促進損傷肌腱的癒合。這種不含外源性支架的肌腱樣組織有希望成為肌腱組織工程技術的新手段,在肌腱再生和肌腱修復的臨床應用及基礎研究方面有廣泛的前景。 / Tendon injuries are common and tendon healing outcome is poor, because tendon contains few cells with limited capacities for self-repair/regeneration. The current treatments on tendon injuries including drugs, physiotherapy, and surgery are not ideal and there is a need for the development of novel tissue-engineering strategies for tendon repair. / Previous studies have shown positive effects of bone marrow-derived mesenchymal stem cells (BMSCs), dermal fibroblast, tenocytes, and embryonic stem cells-derived MSCs for tendon repair/regeneration. However, these cells have limitations including insufficient differentiation; risk of teratoma and ectopic bone formation etc. Recently, stem cells have been isolated from tendons of human, mouse, rat and rabbit and considered as a new alternative cell source for tendon tissue engineering (TDSCs). For tenogenic differention of MSCs, connective tissue growth factor (CTGF) and ascorbic acid (one form of vitamin C) are reported to play important roles in promoting collagen and other extracellular matrixes (ECM) production, and regulating the MSCs differentiation towards tenogenic pathway. / The aims of the current study are: (1) To investigate the use of TDSCs in tendon repair in a rat acute patellar tendon injury model; (2) To test the effects of CTGF and ascorbic acid on tenogenic differentiation of TDSCs in vitro; (3) To construct scaffold-free tendon-like tissues in vitro using tenogenically differentiated TDSCs; (4) To promote tendon healing by engineered tendon-like tissues in a rat acute patellar tendon injury model. / In the rat acute patellar tendon injury model, in contract to control group, TDSCs treated group showed better alignment of collagen fibers and the significantly higher ultimate stress and Young’s modulus, indicating TDSCs may be an alternative cell source for tendon repair. The effects of CTGF and ascorbic acid on tenogenic differentiation of TDSCs were also confirmed with higher expression of tendon related markers such as Tenomodulin, Scleraxis, Thbs4, Type I Collagen, etc; with higher production of collagenous proteins. After treatment with CTGF and ascorbic acid for 2 weeks, TDSCs can form cell sheets, which can be harvested, rolled up on a U-shaped spring to form tendon-like tissues in culture, which had loose extracellular matrices and randomly distributed TDSCs and also expressed Tenomodulin, Type I & III collagen. Following transplantation of the engineered tendon-like tissue in nude mice for 8 and 12 weeks, neo-tendon tissues were formed, with thin and parallel collagen fibrils and extracellular matrices of Tenomodulin, Type I & III collagen. Finally in the rat patellar tendon window injury model, data suggested that the engineered tendon-like tissue could promote tendon healing with significantly improved histological features and biomechanical properties comparing to the control group. / In conclusion, our study has indicated that TDSCs can be an alternative cell source in tendon tissue engineering for tendon regeneration. The tenogenic differentiation of TDSCs, induced by CTGF and ascorbic acid in vitro, produces cell sheets, which can be constructed tendon-like tissues in vitro; to form neo-tendon and repair tendon injuries in vivo. The use of engineered scaffold-free tendon tissue for tendon tissue engineering has potentials in clinical application for tendon repair/regeneration. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Ni, Ming. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 107-126). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / DEDICATION --- p.I / ACKNOWLEDGEMENT --- p.II-III / TABLE OF CONTENTS --- p.IV-IX / PUBLICATIONS --- p.X-XII / ABBREVIATION --- p.XIII-XV / ABSTRACT (ENGLISH) --- p.XVI-XVIII / ABSTRACT (CHINESE) --- p.XIX-XX / Chapter CHAPTER 1 --- Introduction --- p.1 / Chapter 1.1 --- Epidemiology of tendon injury --- p.1 / Chapter 1.2 --- Healing process of tendon injury --- p.1 / Chapter 1.3 --- Tendon tissue engineering for tendon repair --- p.2 / Chapter 1.4 --- Stem cells in tendon repair --- p.2 / Chapter 1.5 --- Tenogenic differentiation of tendon derived stem cells --- p.7 / Chapter 1.6 --- Growth factors for tenogenic differentiation --- p.8 / Chapter 1.7 --- Vitamin C for tenogenic differentiation --- p.9 / Chapter 1.8 --- Summary --- p.10 / Chapter CHAPTER 2 --- Hypothesis, Objectives and Study Design --- p.11 / Chapter 2.1 --- Hypothesis --- p.11 / Chapter 2.1.1 --- Overall hypothesis --- p.11 / Chapter 2.1.2 --- Specific hypothesis --- p.11 / Chapter 2.2 --- Objectives --- p.12 / Chapter 2.3 --- Study design --- p.12 / Chapter 2.3.1 --- Study I --- p.12 / Chapter 2.3.2 --- Study II --- p.14 / Chapter 2.3.3 --- Study III --- p.14 / Chapter 2.3.4 --- Study IV --- p.17 / Chapter CHAPTER 3 --- Tendon-derived Stem Cells (TDSCs): A New Cell Source for Tendon Repair (Study I) --- p.19 / Chapter 3.1 --- Materials and Methods --- p.19 / Chapter 3.1.1 --- Isolation and characterization of rat GFP-TDSCs --- p.19 / Chapter 3.1.2 --- Animal surgery --- p.20 / Chapter 3.1.3 --- Ultrasound imaging --- p.25 / Chapter 3.1.4 --- Histology --- p.27 / Chapter 3.1.5 --- Biomechanical test --- p.27 / Chapter 3.1.6 --- Ex vivo fluorescence imaging --- p.28 / Chapter 3.1.7 --- Data analysis --- p.29 / Chapter 3.2 --- Results --- p.29 / Chapter 3.2.1 --- Gross observation of the injured knee and patellar tendon --- p.29 / Chapter 3.2.2 --- Histology of regenerated tendon tissue --- p.30 / Chapter 3.2.3 --- Biomechanical test of regenerated tendon tissue --- p.32 / Chapter 3.2.4 --- Ex vivo fluorescence imaging of GFP-TDSCs --- p.33 / Chapter 3.2.5 --- Ultrasound imaging of wound gap volume --- p.34 / Chapter 3.3 --- Discussion --- p.35 / Chapter 3.4 --- Conclusion --- p.50 / Chapter CHAPTER 4 --- Tenogenic Differentiation of Tendon-derived Stem Cells (TDSCs) (Study II) --- p.51 / Chapter 4.1 --- Materials and Methods --- p.51 / Chapter 4.1.1 --- Tenogenic differentiation of tendon-derived stem cells (TDSCs) --- p.51 / Chapter 4.1.2 --- Quantification of collagenous proteins --- p.51 / Chapter 4.1.3 --- Quantitative Real Time PCR (qRT-PCR) --- p.52 / Chapter 4.1.4 --- Data analysis --- p.54 / Chapter 4.2 --- Results --- p.55 / Chapter 4.2.1 --- Quantification of collagenous proteins --- p.55 / Chapter 4.2.2 --- Tenogenic, osteogenic and chondrogenic markers mRNA expression --- p.57 / Chapter 4.2.3 --- Tendon extracellular matrix markers mRNA expression --- p.57 / Chapter 4.3 --- Discussion --- p.59 / Chapter 4.4 --- Conclusion --- p.66 / Chapter CHAPTER 5 --- Engineered Scaffold-free Tendon Tissue Produced by Tendon-derived Stem Cells (TDSCs) Cell Sheet (Study III) --- p.67 / Chapter 5.1 --- Materials and Methods --- p.67 / Chapter 5.1.1 --- In vitro engineered scaffold-free tendon tissue by TDSCs cell sheet --- p.67 / Chapter 5.1.2 --- In vivo neo-tendon formation using engineered scaffold-free tendon tissue in nude mouse model --- p.67 / Chapter 5.1.3 --- Histology and immunohistochemistry staining --- p.68 / Chapter 5.1.4 --- In vivo fluorescence imaging --- p.69 / Chapter 5.1.5 --- Data analysis --- p.70 / Chapter 5.2 --- Results --- p.70 / Chapter 5.2.1 --- Gross observation of TDSCs cell sheet and engineered scaffold-free tendon tissue --- p.70 / Chapter 5.2.2 --- Histological and immunohistochemical characteristics in engineered scaffold-free tendon tissue --- p.71 / Chapter 5.2.3 --- Gross observation and in vivo fluorescence imaging of neo-tendon tissue --- p.74 / Chapter 5.2.4 --- Histology of neo-tendon tissue --- p.75 / Chapter 5.2.5 --- Immunohistochemistry staining in neo-tendon tissue --- p.76 / Chapter 5.3 --- Discussion --- p.78 / Chapter 5.4 --- Conclusion --- p.82 / Chapter CHAPTER 6 --- Use of Engineered Scaffold-free Tendon Tissue for Tendon Repair (Study IV) --- p.83 / Chapter 6.1 --- Materials and methods --- p.83 / Chapter 6.1.1 --- Animal surgery --- p.83 / Chapter 6.1.2 --- Ex vivo fluorescence imaging --- p.84 / Chapter 6.1.3 --- Histology and immunohistochemistry staining --- p.85 / Chapter 6.1.4 --- Biomechanical test --- p.86 / Chapter 6.1.5 --- Ultrasound imaging --- p.87 / Chapter 6.1.6 --- Data Analysis --- p.87 / Chapter 6.2 --- Results --- p.88 / Chapter 6.2.1 --- Gross observation of the injured knee and patellar tendon --- p.88 / Chapter 6.2.2 --- Histology of regenerated tendon tissue --- p.89 / Chapter 6.2.3 --- Tendon specific and ECM markers expression in regenerated tendon tissue --- p.91 / Chapter 6.2.4 --- Osteogenic and chondrogenic specific markers expression in neo-tendon tissue --- p.93 / Chapter 6.2.5 --- The fate of the transplanted engineered scaffold-free tendon tissue --- p.93 / Chapter 6.2.6 --- Biomechanical test of regenerated tendon tissues --- p.94 / Chapter 6.3 --- Discussion --- p.96 / Chapter 6.4 --- Conclusion --- p.102 / Chapter CHAPTER 7 --- General Conclusions --- p.103 / Chapter 7.1 --- General discussion --- p.103 / Chapter 7.2 --- General conclusions --- p.105 / FUNDING --- p.106 / REFERENCES --- p.107 / APPENDIX --- p.127
48

Diferença na reconstituição imune específica para o citomegalovírus pós transplante de células tronco-hematopoiéticas autólogo e alogênico

Moreno, Juliana Ribeiro do Prado January 2019 (has links)
Orientador: Clarisse Martins Machado / Resumo: O citomegalovírus (CMV) é uma das principais causas de morbidade e mortalidade em receptores de transplante de células tronco hematopoiéticas. As complicações que podem surgir após o transplante são numerosas e diversas, estando o CMV e a doença do enxerto contra o hospedeiro (DECH) entre as mais importantes. A infecção pelo CMV pode afetar qualquer órgão e células do sistema imunitário e os receptores soropositivos para o CMV estão sob risco de reativação. Receptores de transplante alogênico de células tronco-hematopoiéticas têm um risco significantemente maior de infecção por CMV em comparação com receptores de transplante autólogo em função do uso de imunossupressores na profilaxia da DECH. O trabalho teve como objetivo a implantação e a avaliação da reconstituição imune CMV-específica através de uma técnica de dosagem de interferon-gama (Quantiferon-CMV). Observou-se que a reconstituição imune CMV-específica foi diferente em cada tipo de TCTH. Os pacientes autólogos mantiveram a imunidade até o d+120, diferentemente dos alogênicos. Já nos alogênicos, observou-se que os pacientes que realizaram TCTH do tipo aparentado, obtiveram uma recuperação imune CMV-específica melhor que o não-aparentado e o haploidêntico até o D+60. Nenhum paciente do tipo haploidêntico recuperou a imunidade no D+30. No D+90 observou-se que cerca de 60% dos receptores de transplantes alogênicos recuperaram a imunidade CMV-específica, variando entre 55,5% a 67,5. / Mestre
49

Fatores clínicos, econômicos e infecções em pacientes onco hematológicos submetidos a quimioterapia e/ou transplante de células tronco hematopoéticas

Neto, Denise Pereira January 2012 (has links)
INTRODUÇÃO: As infecções causadas pela neutropenia severa são as causas mais frequentes de morbidade em pacientes submetidos à quimioterapia e Transplante de Células Tronco Hematopéticas (TCTH). Além da neutropenia prolongada vários fatores como o uso de dispositivos intravenosos, mucosite, condições clinicas prévias, tipo de tratamento e tempo de internação também contribuem para o desenvolvimento de infecções. A classe socioeconômica parece influenciar em uma série de desfechos no tratamento do câncer. A análise destas correlações é importante para determinar um melhor desfecho clinico para estes pacientes. OBJETIVO: verificar a relação entre perfil clinico e condições econômicas com o desenvolvimento de complicações infecciosas em pacientes submetidos a quimioterapia e TCTH. MÉTODO: Foi realizado um estudo de coorte prospectivo com 89 pacientes adultos e crianças submetidos a quimioterapia e/ou TCTH que internaram na Unidade de Ambiente Protegido (UAP) do Hospital de Clinicas de Porto Alegre (HCPA). O período de coleta de dados foi de Abril de 2011 a Maio de 2012, e o método foi através de acompanhamento clínico diário e análise de prontuário eletrônico. Foram analisados os desfechos de infecções correlacionados com o perfil clinico e status econômico. RESULTADO: Pacientes com comorbidades foram 35(39,3%). A classe econômica foi classificada A+B igual (37) 41,6% e classe C+D igual (52) 58,6%. Dos pacientes analisados 85,4% apresentaram algum tipo de infecção, sendo as bacterianas as mais frequentes (37) 41,6% e mucosite verificada em (79) 88,8%. Em relação à classe econômica, o grupo C+D apresentou RR 1,2 e P 0,005 para o desfecho infecção. CONCLUSÃO: constatamos que pacientes submetidos à quimioterapia e/ou TCTH com comorbidades apresentam maior risco para infecções, e que o grupo de classe econômica A+B foi associada a menor incidência de infecções e de tempo de internação que a classe C + D durante o período de tratamento. / INTRODUCTION: The infections caused by severe Neutropenia are the most frequent causes of morbidity and mortality in patients undergoing chemotherapy and Hematopoietic Stem Cell Transplantation (HSCT). Besides the extended Neutropenia, other factors like the use of intravenous devices, mucositis, previous clinical conditions, kind of treatment, economic class and length of stay in hospital contribute to the development of infections. The present analysis of these correlations is important to establish the best clinical outcome for these patients. OBJECTIVE: The objective of this study is to verify the clinical profile, the economic conditions and the infectious complications in patients undergoing chemotherapy and HSCT. METHOD: A prospective cohort study was performed with 89 patients, adults and children, undergoing chemotherapy and/or HSCT admitted at the Unit of Protected Environment (UAP) at the Hospital de Clínicas de Porto Alegre (HCPA). The data were collected from April 2011 to May 2012, through the method of a daily monitoring and analysis of the electronic medical records. The outcomes of infections correlated to the clinical profile and economic status were analyzed. RESULT: Patients with comorbidity represented 39,3%. The economic class was ranked as: A+B equal to 41,6% and class C+D equal to 58,6%. From the analyzed patients, 84,5 % presented some kind of infection, with more frequency to the bacterial infection (41,6%) and mucositis representing 88,8%. In relation to the economic class the C+D group presented RR 1,2 and P 0,005 to the outcome of the infection. CONCLUSION: We concluded that patients undergoing chemotherapy and/or HSCT with comorbidities presented a higher risk of infection, and that the A+B economic class was associated to a lower incidence of infections and length of stay in hospital than the class C+D during the period of treatment.
50

Studies of tumor and MSCs interactions. / Studies of tumor and mesenchymal stem cells interactions

January 2013 (has links)
惡性腫瘤嚴重威脅著人類的身體健康,其治療也成為人類關注的焦點。傳統的化學療法和放射療法由於缺乏特異性,取得療效的同時往往也帶來較大的毒副作用。隨著對腫瘤發生發展分子機制認識的不斷深入,腫瘤的基因治療已成為攻克和治愈腫瘤最具希望和挑戰的研究領域。近年來研究發現骨髓間充斥幹細胞(MSCs)可被募集至腫瘤或損傷部位并參與腫瘤生長或組織修復,研究證明間充斥幹細胞通過靜脈注入帶瘤鼠(比如乳腺癌、膠質瘤、結腸癌及黑色素瘤)體內后,特異性的分佈于生長中的腫瘤中。這種特異性向腫瘤組織趨化轉移的特性使得骨髓間充斥幹細胞成為腫瘤基因靶向治療的載體的理想細胞。酶蛋白基因如單純皰疹病毒胸苷激酶(HSV-TK)可以使一些無毒或低毒的前藥轉化為強細胞毒性物質,殺死腫瘤細胞。我們前期實驗結果表明,通過遺傳改造后的表達TK基因的MSCs在GCV的存在下,具有殺傷腫瘤細胞抑制腫瘤生長的能力。但沒有改造的MSCs遷移至腫瘤之後可能會分化成成纖維細胞或者腫瘤基質細胞等支持腫瘤生長,但其命運和影響到底如何,我們怎麼樣進一步促進其向腫瘤的遷移以提高殺傷腫瘤的效率是本研究需要解決的問題。 / 本研究擬採用免疫螢光組織化學技術和分子生物學等技術研究和觀察MSCs對腫瘤(以乳腺癌,前列腺癌為例)的趨化過程及其在腫瘤生長中的作用,在在此基礎上研究促進攜帶HSV-TK自殺基因的MSCs的腫瘤靶向性細胞治療策略,採用分子和細胞生物學等方法評估其對荷瘤鼠體內腫瘤殺傷的原理,為利用TK-MSCs腫瘤的靶向治療奠定基礎。 / 研究結果顯示體外共培養的條件下,小鼠骨髓間充斥幹細胞可促進小鼠乳腺癌細胞增長,且增長速度同培養體系中間充斥幹細胞數目呈正相關。將兩種細胞混合注射于裸鼠體內,相比共注射小鼠皮膚成纖維細胞,間充斥幹細胞可促進體內腫瘤生長。使用人胚胎骨髓間充斥幹細胞和前列腺癌細胞可得出類似的效果。將腫瘤組織切片分析發現間充斥幹細胞促進體內腫瘤細胞增殖的同時,提高了腫瘤組織內血管密度。體外實驗發現共培養前列腺癌細胞和間充斥幹細胞可促進血管生成且在間充斥細胞內同血管增生相關的蛋白表達量都有相應提高,進一步證實間充斥幹細胞可能通過促進血管增生從而促進腫瘤生長。另外,我們利用人胚胎來源的骨髓間充斥幹細胞建立了穩定表達TK自殺基因的細胞系,且在GCV的存在下具有抑制腫瘤生長的能力。為了促進它們向腫瘤遷移的能力,我們用多柔比星預處理腫瘤細胞,和沒處理過的對照組相比,能增強對表達TK的間充斥幹細胞的招募能力。且在聯合利用多柔比星和TK的條件下,腫瘤生長能得到較大程度的抑制,這種抑制作用强於單獨使用多柔比星和表達自殺基因的間充斥幹細胞系統。初步認為是多柔比星的處理能增強腫瘤組織內炎性介質的分泌從而增強間充斥幹細胞的遷移達到增強自殺基因系統殺死腫瘤細胞的目的。 / 總的來說,雖然間充質幹細胞對腫瘤的生長存在一定的促進作用,但我們仍能對其進行遺傳改造,且在其它抗腫瘤藥的配合下達到最大的抗腫瘤效果。 / Eradication of cancer, especially when it has metastasized is extremely difficult and conventional cancer therapies are simply unable to specifically target tumors/cancers, thus causing unwanted side effects and complications. Recently, it has been shown that bone marrow mesenchymal stem cells (MSCs) are able to migrate specifically to tumors and contribute to the formation of tumor-associated stroma. These properties make MSCs good candidates as anti-tumor agent delivery vehicles and lead to a great deal of interest in the possibility of genetically modifying MSCs to express anticancer molecules and using them as specific targeted anticancer agents. We and others have showed that MSCs have the ability to migrate towards various cancer cells including breast, colon, fibrosarcoma and prostate cancer cells. Suicide gene therapy is widely used in cancer gene therapy. When stably infected with herpes simplex virus thymidine kinase gene by lentivirus, TK-MSCs maintained their MSCs characters and tumor tropism potential and significantly inhibited tumor growth, in the presence of the pro-drug ganciclovir (GCV). Improve MSCs homing to tumor tissue as anti-tumor gene therapy vehicles and maximizing their tumor killing effects is highly warranted. Furthermore, MSCs interact with tumor cells in numerous ways, which have the potential to support or suppress tumor growth. Therefore the fate and role of MSCs engrafted in tumor sites need to be clarified in order to making better use of these cells as anti-cancer agent delivery vehicles. / The aims of the current study are: (1) to study the role and fate of MSCs homed into the tumors; (2) to establish human bone marrow MSCs that stably express the TK genes; (3) to investigate the methods that enhance the anti-tumor efficiency of TK-MSCs. / In this study, bone marrow-derived mesenchymal stem cells from mice or human fetus were isolated and characterized. Effects of BM-MSCs on tumor cell proliferation in vitro were analyzed in a co-culture system with mouse breast cancer cell 4T1 cells. Both co-culture with BM-MSCs and treatment with MSC-conditioned medium led to enhanced growth of 4T1 cells. Co-injection of 4T1 cells and MSCs into nude mice led to increased tumor size compared with injection of 4T1 cells alone. Identical experiments using human prostate cancer cell DU145 cells and hBM-MSCs instead of 4T1 cells and mBM-MSCs yielded similar results. Compared with tumors induced by injection of cancer cells alone, tumor vessel area was greater in tumors from co-injection of 4T1 or DU145 with BM-MSCs, which correlated with decreased central tumor necrosis and increased tumor cell proliferation. Furthermore, both conditioned medium from co-cultures of hBM-MSCs and DU145 cells or hBM-MSCs alone was able to induce angiogenesis in human umbilical vein endothelial cells (HUVEC). When hBM-MSCs exposed to DU145 cells environment, the expression of markers associated with neovascularization (α-SMA, VEGF, TGF-β and IL6) were increased. Together, these results indicate that MSCs promote tumor growth both in vitro and in vivo and suggest that tumor promotion in vivo may be attributable in part to enhanced angiogenesis. / Immortalized human fetal bone marrow-derived MSCs (hfBMSCs) expressing herpes simplex virus thymidie kinase was established by conventional lentiviral transduction method. Functional expression of TK was evaluated by cytotoxicity in the presence of its prodrug GCV. SV40-TK-hfBMSCs exhibited comparable proliferation, surface phenotype expression, multi-differentiation potential and tumor-tropic migration ability as hfBMSCs. By measurement of tumor volume, repeated injection of the SV40-TK-hfBMSCs and subsequent consecutive GCV administration could suppress tumor growth in DU145 or PC3 human prostate tumor xenograft nude mice model without causing weight loss. However, its clinical applications are still limited. Alternative strategies have been pursued in this study by the use of combination therapy with cytotoxic chemotherapy to improve the overall efficacy of the TK-hfBMSCs/GCV system. / TK-hfBMSCs/GCV was evaluated alone or combined with low-dose doxorubicin in human prostate carcinoma DU145 xenografts in nude mice, testing for effects on local growth and overall survival. Tissues were evaluated through immunofluorescence and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining (TUNEL) for treatment effects on tumor cell proliferation and apoptosis. Transwell migration assay was used to access the migration ability of TK-hfBMSCs to tumor cells upon doxorubicin treatment and caspase-3 activity was conducted for test the tumor cells apoptosis under TK-hfBMSCs/GCV, doxorubicine, or combination of the two compound treatments respectively. Only minimal growth inhibition was observed in DU145 after treatment with TK-hfBMSCs/GCV or doxorubicin alone at doses and time points as indicated. In contrast, the combination of both agents resulted in a significant growth inhibition. Caspase-3, plays a central role in the execution-phase of cell apoptosis, was increased by TK-hfBMSCs/GCV or doxorubicine and also to a much greater extent by the combination treatment. Treatment by TK-hfBMSCs/GCV resulted in only a slight decrease in tumor growth compared with controls. Treatment with low-dose doxorubicin alone resulted in a small, nonstatistically significant decrease in tumor growth; In contrast, combined low-dose doxorubicin and TK-hfBMSCs/GCV was markedly inhibitory compared with control, doxorubicin alone, or TK-hfBMSCs/GCV alone. During the whole treatment process, no significant weight loss was observed. Furthermore, combined therapy induced increased area of necrosis, significant apoptosis and decreased tumor cell proliferation in treated tumors. Taken together, low dosage of doxorubicin could be used in combination with TK-hfBMSCs based suicide gene therapy. / In conclusion, we have demonstrated that BM-MSCs could increase the growth of human prostate cancer and mouse breast cancer. The promotion effect may partly attribute to the increased expression of pro-angiogenic factors in BM-MSCs in tumor microenvironment and subsequent enhancement in angiogenesis and tumor growth. The current study also suggests combination of TK-hfBMSCs/GCV and doxorubicin was more effective in inhibiting prostate cancer cells growth than TK-hfBMSCs/GCV or doxorubicin alone. Although many problems need to be resolved for further application, our study provided the possibility of a new strategy of suicide gene-based therapy accompanied by low dosage of chemotherapy in treating prostate cancer. Therefore MSCs were described as a “double-edged sword in their interaction with tumors. However, if MSCs are suitably engineered with anticancer genes they could be employed as a valuable “single-edged sword“ against cancers. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhang, Ting. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 120-158). / Abstracts also in Chinese. / ACKNOWLEDGEMENT --- p.ii / PUBLICATIONS --- p.vii / ABSTRACT --- p.xiii / Chapter CHAPTER 1 --- Introduction --- p.1 / Chapter 1.1 --- Mesenchymal stem cells (MSCs) --- p.2 / Chapter 1.2 --- Tumor microenvironment and involvement of MSCs in tumor establishment --- p.5 / Chapter 1.3 --- Tumors-tropic characteristics of MSCs --- p.15 / Chapter 1.4 --- Impact of MSCs on in vivo tumors --- p.21 / Chapter 1.5 --- In vivo imaging demonstrating MSCs tumor-homing potentials --- p.25 / Chapter 1.6 --- Evidence for use of MSCs as anti-tumor agents delivery vehicles --- p.26 / Chapter 1.7 --- Homing strategies to enhance efficacy and safety of MSCs therapy --- p.32 / Chapter 1.8 --- Summary --- p.35 / Chapter CHAPTER 2 --- Hypotheses, Objectives and Study Design --- p.35 / Chapter 2.1 --- Hypothesis --- p.35 / Chapter 2.2 --- Objective --- p.36 / Chapter 2.3 --- Study design --- p.37 / Chapter CHAPTER 3 --- Bone Marrow-derived Mesenchymal Stem Cells Promote Growth and Angiogenesis of Breast and Prostate Tumors (Study I) --- p.40 / Chapter 3.1 --- Materials and Methods --- p.40 / Chapter 3.2 --- Results --- p.49 / Chapter 3.3 --- Discussion --- p.64 / Chapter 3.4 --- Conclusions --- p.67 / Chapter CHAPTER 4 --- Immortalized human fetal bone marrow-derived mesenchymal stem cell expressing anti-tumor suicide gene for anti-tumor therapy in vitro and in vivo (Study II) --- p.68 / Chapter 4.1 --- Materials and Methods --- p.68 / Chapter 4.2 --- Results --- p.73 / Chapter 4.3 --- Discussion --- p.85 / Chapter CHAPTER 5 --- Enhanced antitumor effects by combination therapy using mesenchymal stem cell expressing anti-tumor suicide gene and Doxorubicin in a xenograft mouse model (Study III) --- p.89 / Chapter 5.1 --- Materials and Methods --- p.89 / Chapter 5.2 --- Results --- p.97 / Chapter 5.3 --- Discussion --- p.111 / Chapter CHAPTER 6 --- General discussion and conclusions --- p.116 / Chapter 6.1 --- General discussion --- p.116 / Chapter 6.2 --- General conclusions --- p.119 / FUNDING --- p.120 / REFERENCE --- p.120

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