• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 101
  • 95
  • 47
  • 15
  • 7
  • 7
  • 5
  • 5
  • 4
  • 1
  • Tagged with
  • 310
  • 310
  • 138
  • 123
  • 92
  • 81
  • 62
  • 59
  • 57
  • 56
  • 55
  • 39
  • 38
  • 32
  • 30
  • 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.
131

Compara??o entre protocolos para obten??o de plasma rico em plaquetas em c?es: estudo celular / Comparison between protocols for obtaining platelet-rich plasma in dogs: a cellular study

VIDAL JUNIOR, Andr? William Masseaux 15 February 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-13T21:42:04Z No. of bitstreams: 1 2017 - Andr? William Masseaux Vidal J?nior.pdf: 1275550 bytes, checksum: d2d211215832b8ab2e53ab8d6da5ae4b (MD5) / Made available in DSpace on 2018-09-13T21:42:04Z (GMT). No. of bitstreams: 1 2017 - Andr? William Masseaux Vidal J?nior.pdf: 1275550 bytes, checksum: d2d211215832b8ab2e53ab8d6da5ae4b (MD5) Previous issue date: 2017-02-15 / It was proposed by this study to evaluate two protocols (PA and PB) to obtain autologous canine PRP, which is easy to perform in an ambulatory (semiautomatic method) and of good quality (platelet concentration, qualitative evaluation of platelet morphology and low contamination with Erythrocytes), to later propose different therapeutic indications of these PRPs as tissue modulating agents, according to the observed cellular leukocyte pattern. For this purpose, 20 dogs (Canis lupus familiaris) were used at the UFRRJ (HV) Veterinary Hospital, males and females, aged between 1 and 7 years (mean 4 years), considered clinically and hematologically healthy for elective surgeries and / or routine consultations. After adequate trichotomy and antisepsis, 8 mL of blood were collected by venipuncture of the jugular, being immediately packed in two 4 mL flasks, vacuntainer type, containing sodium citrate 3,2%. Protocol A using double centrifugation with 210 xG and 370 xG and protocol B using double centrifugation with 140 x G and 330 x G. PRP samples obtained from each protocol were used to count platelets, erythrocytes and leukocytes in the Neubauer chamber, differential leukocyte counting and observation of platelet morphology in smears. Data (mean and standard deviations) were analyzed by the 95% probability t test (p <0,05) using Pearson's correlation to test the relationship between platelet and erythrocyte counts, platelets and leukocytes and leukocytes in Relation to red blood cells. There was a very weak negative correlation between platelets and leukocytes (? = -0,03), weak negative between platelets and erythrocytes (? = -0,3) and strong positive correlation between leukocytes and erythrocytes (? = 0,75). Although Protocol B did not reach the desired one million platelets average (979300 ? 79631 cells / ?L), both protocols, A and B (4,42 ? 1,61 and 3,85 ? 1,55 times more platelets than Total blood, respectively) (p <0,05) were efficient in concentrating platelets. The cytoplasmic prolongations evidencing platelet activation were present in 26,55 ? 6,72% of platelets of protocol A and 26,25 ? 7,03% in those of protocol B (p> 0,05). A and B presented a small number of red blood cells (p> 0,05), which were considered to be contaminants of the samples and, for the quantity of leukocytes, protocol A presented more white blood cells (p <0,05) than protocol B with higher concentrations of basophils , and lymphocytes. / Foi proposto por esse estudo avaliar dois protocolos (PA e PB) para obten??o de PRP canino aut?logo, de f?cil execu??o em ambulat?rio (m?todo semiautom?tico) e de boa qualidade (capacidade de concentra??o de plaquetas, avalia??o qualitativa da morfologia das plaquetas e reduzida contamina??o com eritr?citos), para posteriormente propor diferentes indica??es terap?uticas desses PRP como agentes moduladores de recupera??o tecidual, de acordo com o padr?o celular leucocit?rio observado. Para isso foram utilizados 20 c?es (Canis lupus familiaris) atendidos no Hospital Veterin?rio da UFRRJ (HV), machos e f?meas, com idade variando entre 1 e 7 anos (m?dia 4 anos), considerados saud?veis clinica e hematologicamente que se destinavam para cirurgias eletivas e/ou consultas de rotina. Ap?s tricotomia e antissepsia adequadas, eram coletados 8 mL de sangue por venopun??o da jugular sendo imediatamente acondicionados em dois frascos de 4 mL, do tipo vacuntainer, contendo citrato de s?dio a 3,2%. O protocolo A utilizando centrifuga??o dupla com 210 xG e 370 xG e protocolo B utilizando centrifuga??o dupla com 140 xG e 330 xG. Amostras de PRP obtidas a partir de cada protocolo foram destinadas a contagem de plaquetas, hem?cias e leuc?citos em c?mara de Neubauer, contagem diferencial dos leuc?citos e observa??o da morfologia das plaquetas em esfrega?os. Analisou-se os dados (m?dias e desvios padr?o) pelo Teste t com 95% de probabilidade (p<0,05) utilizando-se correla??o de Pearson para testar a rela??o entre a contagem de plaquetas e hem?cias, plaquetas e leuc?citos e leuc?citos em rela??o as hem?cias. Houve correla??o negativa muito fraca entre plaquetas e leuc?citos (?= -0,03), negativa fraca entre plaquetas e hem?cias (?= -0,3) e correla??o positiva forte entre leuc?citos e hem?cias (?=0,75). Embora o protocolo B n?o tenha alcan?ando a m?dia um milh?o de plaquetas desejado (979300 ? 79631 c?lulas/?L), ambos os protocolos, A e B (4,42 ? 1,61 e 3,85 ? 1,55 vezes mais plaquetas que o sangue total, respectivamente) (p<0,05) foram eficientes em concentrar plaquetas. Os prolongamentos citoplasm?ticos evidenciando ativa??o plaquet?ria estiveram presentes em 26,55 ? 6,72 % das plaquetas do protocolo A e 26,25 ? 7,03 % nas do protocolo B (p>0,05). PA e PB apresentaram reduzido n?mero de hem?cias (p>0,05) consideradas contaminantes das amostras e, quanto a quantidade de leuc?citos, o protocolo A apresentou mais gl?bulos brancos (p<0,05) que o protocolo B com maiores concentra??es de bas?filos, segmentados e linf?citos.
132

Rejuvenation of Aged Heart Explant-Derived Cells for Repair of Ischemic Cardiomyopathy

Rafatian, Ghazaleh 26 February 2019 (has links)
In autologous stem cell therapy, cell characteristics determine the potency of stem cells for regeneration. Aging and ischemia are two factors that are often neglected in pre-clinical tests for stem cell therapy. Here, we characterized cardiac explant-derived cells (EDCs) with a focus on distinguishing the effect of age and ischemia and then we looked for the effects of the combination of the two factors. We observed that ischemia worsens the age effect on EDCs. EDCs that were derived from aged mice with a history of myocardial infarction showed the highest number of senescent cells with dysregulation of the DNA repair system resulting in activation of cell cycle checkpoints. We over-expressed the anti-senescence Mybl2 transcription factor in EDCs from ischemic aged mice. The senescent state, paracrine profile and superoxide dismutase antioxidant enzyme activity improved in these cells. In vivo, we observed a boost in the potency of the Mybl2-modified EDCs, with an increase in short-term engraftment leading to improved heart function in infarcted mice. In general, Mybl2 over-expression rejuvenates senescent EDCs.
133

Genetic Engineering of Excitable Cells for In Vitro Studies of Electrophysiology and Cardiac Cell Therapy

Kirkton, Robert David January 2012 (has links)
<p>Disruption of coordinated impulse propagation in the heart as a result of fibrosis or myocardial infarction can create an asynchronous substrate with poor conduction and impaired contractility. This can ultimately lead to cardiac failure and make the heart more vulnerable to life-threatening arrhythmias and sudden cardiac death. The transplantation of exogenous cells into the diseased myocardium, "cardiac cell therapy," has been proposed as a treatment option to improve compromised cardiac function. Clinical trials of stem cell-based cardiac therapy have shown promising results, but also raised concerns about our inability to predict or control the fate of implanted cells and the electrical consequences of their interactions with host cardiomyocytes. Alternatively, genetically engineered somatic cells could be implanted to selectively and safely modify the cardiac electrical substrate, but their unexcitable nature makes them incapable of electrically repairing large conduction defects. The objective of this thesis was thus to develop a methodology to generate actively conducting excitable cells from an unexcitable somatic cell source and to demonstrate their utility for studies of basic electrophysiology and cardiac cell therapy.</p><p>First, based on the principles of cardiac action potential propagation, we applied genetic engineering techniques to convert human unexcitable cells (HEK-293) into an autonomous source of excitable and conducting cells by the stable forced expression of only three genes encoding an inward rectifier potassium (Kir2.1), a fast sodium (Na<sub>v</sub>1.5), and a gap junction (Cx43) channel. Systematic pharmacological and electrical pacing studies in these cells revealed the individual contributions of each expressed channel to action potential shape and propagation speed. Conduction slowing and instability of induced arrhythmic activity was shown to be governed by specific mechanisms of I<sub>Na</sub> inhibition by TTX, lidocaine, or flecainide. Furthermore, expression of the Na<sub>v</sub>1.5 A1924T mutant sodium channel or Ca<sub>v</sub>3.3 T-type calcium channel was utilized to study the specific roles of these channels in action potential conduction and demonstrate that genetic modifications of the engineered excitable cells in this platform allow quantitative correlations between single-cell patch clamp data and tissue-level function.</p><p>We further performed proof-of-concept experiments to show that networks of biosynthetic excitable cells can successfully repair large conduction defects within primary excitable tissue cultures. Specifically, genetically engineered excitable cells supported active action potential propagation between neonatal rat ventricular myocytes (NRVMs) separated by at least 2.5 cm in 2-dimensional and 1.3 cm in 3-dimensional cocultures. Using elastic films with micropatterned zig-zag NRVM networks that mimicked the tortuous conduction patterns observed in cardiac fibrosis, we showed that electrical resynchronization of cardiomyocyte activation by application of engineered excitable cells improved transverse conduction by 370% and increased cardiac twitch force amplitude by 64%. This demonstrated that despite being noncontractile, engineered excitable cells could potentially improve both the electrical and mechanical function of diseased myocardial tissue. </p><p>Lastly, we investigated how activation and repolarization gradients at the interface between cardiomyocytes and other excitable cells influence the vulnerability to conduction block. Microscopic optical mapping of action potential propagation was used to quantify dispersion of repolarization (DOR) in micropatterned heterocellular strands in which either well-coupled or poorly-coupled engineered excitable cells with a short action potential duration (APD), seamlessly interfaced with NRVMs that had a significantly longer APD. The resulting electrical gradients originating from the underlying heterogeneity in intercellular coupling and APD dispersion were further manipulated by the application of barium chloride (BaCl2) to selectively prolong APD in the engineered cells. We measured how the parameters of DOR affected the vulnerable time window (VW) of conduction block and found a strong linear correlation between the size of the repolarization gradient and VW. Reduction of DOR by BaCl2 significantly reduced VW and showed that VW correlated directly with dispersion height but not width. Conversely, at larger DOR, VW was inversely correlated with the dispersion width but independent of the dispersion height. In addition, despite their similar APDs, poorly-coupled excitable cells were found to significantly increase the maximum repolarization gradient and VW compared to well-coupled excitable cells, but only at larger DOR.</p><p>In summary, this thesis presents the novel concept of genetically engineering membrane excitability and impulse conduction in previously unexcitable somatic cells. This biosynthetic excitable cell platform is expected to enable studies of ion channel function in a reproducible tissue-level setting, promote the integration of theoretical and experimental studies of action potential propagation, and stimulate the development of novel gene and cell-based therapies for myocardial infarction and cardiac arrhythmias.</p> / Dissertation
134

CD19-targeting CAR T Cells for Treatment of B Cell Malignancies : From Bench to Bedside

Karlsson, Hannah January 2014 (has links)
Immunotherapy for cancer is a young research field progressing at high speed. The first chimera of an antibody and a signaling chain was designed by Zelig Eshhar and was later further developed to enhance existing T cell therapy by combining a single-chain fragment of an antibody with the CD3 zeta chain of the TCR complex. T cells expressing these chimeric antigen receptors (CARs) could recognize and specifically kill tumor cells. However the T cells, lacked in persistence and tumor rejection did not occur. Thus, the CAR constructs have been improved by providing the T cell with costimulatory signals promoting activation. The focus of this thesis has been to evaluate second and third generation αCD19-CAR T cells for the treatment of B cell leukemia and lymphoma. B cell tumors commonly upregulate anti-apoptotic proteins such as Bcl-2, which generates therapy resistance. In the first paper a second generation (2G) αCD19-CD28-CAR T cell was combined with the Bcl-2 family inhibitor ABT-737. ABT-737 sensitized tumor cells to CAR T cell therapy and may be an interesting clinical combination treatment. In paper II, the phenotype and function of a third generation (3G) αCD19-CD28-4-1BB-CAR T cell were evaluated. B cell-stimulated CAR T cells showed increased proliferation and an antigen-driven accumulation of CAR+ T cells. 3G CAR T cells had equal cytotoxic capacity, similar lineage, memory and exhaustion profile phenotype compared to 2G CARs. However, 3G CAR T cells proliferated better and had increased activation of intracellular signaling pathways compared to 2G CAR T cells. In paper III, αCD19-CD28-4-1BB-CAR T cells were used to stimulate immature dendritic cells leading to an upregulation of maturation markers on co-cultured dendritic cells. Hence, CAR T cells may not only directly kill the tumor cells, but may induce bystander immunity that indirectly aids tumor control. This thesis also include supplementary information about the development and implementation of protocols for GMP production of CAR T cell batches for a phase I/IIa clinical trial currently ongoing for patients with refractory B cell leukemia and lymphoma. So far, two patients have safely been treated on the lowest dose.
135

Adoptive T cell therapy of breast cancer: defining and circumventing barriers to T cell infiltration in the tumour microenvironment.

Martin, Michele 03 November 2011 (has links)
In the era of personalized cancer treatment, adoptive T cell therapy (ACT) shows promise for the treatment of solid cancers. However, partial or mixed responses remain common clinical outcomes due to the heterogeneity of tumours. Indeed, in many patients it is typical to see a response to ACT in one tumour nodule, while others show little or no response. Thus, defining the tumour features that distinguish those that respond to ACT from those that do not would be a significant advance, allowing clinicians to identify patients that might benefit from this treatment approach. The first chapter of this thesis provides the necessary background to understand the principals behind and components of ACT. This chapter also offers selected historical advances contributing to the current state of the field. The second chapter introduces a novel murine model of breast cancer developed to investigate the tumour-specific mechanisms associated with immune evasion in an ACT setting. The third chapter describes the in vivo characterization of mammary tumour cell lines derived from our mouse model that reliably showed complete, partial or no response to ACT. Using these cell lines, we were able to characterize in vivo tumour-specific differences in cytotoxic T cell trafficking, infiltration, activation, and proliferation associated with response to ACT. In the fourth chapter, we used bioinformatics approaches to develop a preliminary predictive gene signature associated with response to ACT in our mammary tumour model. We used this signature to predict outcome and then test a number of murine mammary tumours in vivo, with promising results, wherein 50% of tumours responded to ACT as predicted based upon gene expression. Thus, using an innovative model for breast cancer, these results suggest that there are tumour-specific features that can be used a priori to predict how a tumour will respond to adoptive T cell therapy. Importantly, these findings might facilitate the design of immunotherapy trials for human breast cancer. / Graduate
136

Potentiel thérapeutique des transplantations autologues et syngéniques de cellules souches olfactives ecto-mésenchymateuses (CSO-EMS) dans deux modèles d'atteintes du système nerveux central (SNC) / Therapeutic potential of autologous and syngeneic olfactory ecto-mesenchymal stem cells (OE-MSCs) tranplantations in two models of central nervous system (SNC) injuries

Sadelli, Kevin 21 December 2017 (has links)
L’objectif de mon travail de thèse était d’évaluer si des autogreffes de cellules souches olfactives ecto-mésenchymateuses (CSO-EMs) restauraient les capacités d’apprentissage et de mémorisation dans un modèle d’amnésie chez le rat, consécutive à une ischémie cérébrale globale (ICG). Cette dernière pouvant avoir lieu suite à un arrêt cardiaque (AC) et conduire à des conséquences neurologiques délétères telles que des atteintes cognitives et/ou sensorimotrices.C’est dans ce contexte scientifique que se sont inscrits mes travaux de recherche dont le premier objectif était de valider un modèle fiable et reproductible d’amnésie chez le rat. Nous avons sélectionné un modèle d’AC induisant une ICG caractérisé par des pertes neuronales ciblées au niveau de la zone CA1 des hippocampes dorsaux associées à des déficits d’apprentissage et de mémorisation.Enfin, la dernière étape de mon projet a consisté à évaluer l'effet des autogreffes de CSO-EMs sur la restauration des fonctions cognitives chez des rats ayant subi une ICG. Tout d’abord, j’ai dû élaborer un protocole permettant le suivi du devenir des CSO-EMs à la suite d’autogreffes, sans en altérer leurs propriétés endogènes. Puis j’ai démontré que ces autogreffes de CSO-EMs GFP+ : i) restauraient les capacités d’apprentissage et de mémorisation, ii) stimulaient la neurogénèse et iii) amélioraient la PLT chez des rats ayant subis une ICG.L’ensemble des données recueillies au cours de ma thèse accordent d’avantage de crédibilité à l’utilisation des CSO-EMs dans le cadre de thérapies menées contre les atteintes du SNC. / The main goal of my thesis was to evaluate whether autografts of ecto-mesenchymal olfactory stem cell (EM-OSCs) restored learning and memory abilities in a rats model of amnesia following global cerebral ischemia (GCI). The latter can occur following cardiac arrest (CA) and lead to deleterious neurological consequences such as cognitive and / or sensorimotor injuries.Finally, the final step in my project was to evaluate the effect of EM-OSCs autografts on restoration of cognitive functions in ischemic rats. First of all, I had to develop a protocol to monitor the fate of EM-OSCs following autografts, without altering their endogenous properties. Then, I demonstrated that these GFP+ EM-OSCs autografts: i) restored learning and memory abilities, ii) stimulated neurogenesis, and iii) improved PLT in ischemic rats. All the data gathered during my thesis give credibility to the use of EM-OSCs in the framework of therapies against the CNS damages.
137

Células-tronco mesenquimais e plasma rico em plaquetas como adjuvantes da cicatrização de lesões cutâneas experimentais em coelhos Nova Zelândia

Garcez, Tuane Nerissa Alves January 2012 (has links)
Muito se tem investido em pesquisa na compreensão dos processos e fenômenos envolvidos nas diversas fases da reparação tissular e, principalmente, no desenvolvimento de recursos e tecnologias com o objetivo de favorecer os avanços no tratamento de feridas. Este trabalho foi realizado com o objetivo de avaliar os efeitos biológicos da associação células-tronco mesenquimais (CTMs) e plasma rico em plaquetas (PRP) como adjuvantes da cicatrização cutânea de feridas padronizadas em coelhos. Foram utilizados 37 coelhos Nova Zelândia, dentre os quais, 36 foram distribuídos em seis grupos: grupo controle (GC), grupo células-tronco mesenquimais (GCTM), grupo plasma rico em plaquetas na forma líquida (GPRPLIQ), grupo plasma rico em plaquetas na forma de gel (GPRPGEL), grupo associação células-tronco mesenquimais e plasma rico em plaquetas na forma liquida (GCTM+PRPLIQ), grupo associação células-tronco mesenquimais e plasma rico em plaquetas na forma de gel (GCTM+PRPGEL). Após indução de lesões cutâneas agudas e padronizadas, os animais receberam o tratamento de acordo com o grupo que compunham. Macroscopicamente, a cada dois dias, foram analisadas as medidas das lesões e calculadas a área e a taxa de cicatrização das mesmas. Amostras para análise microscópica foram coletadas em sete e 14 dias e avaliadas quanto à presença de células inflamatórias, angiogênese, formação de fibrose colagênica, proliferação epitelial e fibroblástica. Com base nos resultados obtidos foi possível concluir que: 1) a associação CTM e PRP em suas frações terapêuticas (CTM+PRPGEL e CTM+PRPLIQ) não acelerou o processo de cicatrização de feridas cutâneas agudas, na avaliação morfométrica aos 14 dias de pós-operatório; 2) a aplicação local da CTM e das frações de PRP quando utilizadas de maneira isolada não conseguiram acelerar o tempo necessário ao processo cicatricial na avaliação morfométrica aos 14 dias de pósoperatório; 3) a utilização do PRP na sua forma líquida obteve índices de epitelização menores em relação ao controle em avaliações histopatológicas aos 14 dias de pósoperatório; 4) à exceção do ocorrido com o grupo PRP líquido, os demais tratamentos não alteraram significativamente as fases inflamatória, proliferativa e inicial do remodelamento, segundo dados histopatológicos; 5) a terapia com as células-tronco mesenquimais promoveu cicatrizes esteticamente melhores na avaliação clínica, especialmente aos 14 dias de observação. Sugere-se a necessidade de novos estudos e a utilização de outras ferramentas diagnósticas para melhores subsídios de interpretação sobre os resultados encontrados. / Much has been invested on research regarding comprehension of the processes and phenomena that are involved in several stages of tissue repairing and mainly on resources and technologies development in order to support advances on wound healing. This study has been performed in order to evaluate the biological effects of mesenchymal stem cells (CTM) and platelet rich plasma (PRP) association as adjuvants on skin healing of standardized wounds in rabbits. Thirty-seven New Zealand rabbits have been used and, among these animals, 36 were allocated into six groups: control group (GC), mesenchymal stem cells group (GCTM), liquid platelet rich plasma group (GPRPLIQ), gel platelet rich plasma group (GPRPGEL), mesenchymal stem cells associated with liquid platelet rich plasma group (GCTM+PRPLIQ) and mesenchymal stem cells associated with gel platelet rich plasma group (GCTM+PRPGEL). After the induction of acute and standardized skin wounds, animals received the treatment according to the group they belonged to. Macroscopically, every two days, wounds measures were taken to calculate their area and healing rate. Samples for microscopically analysis were collected on day 7 and on day 14 and were evaluated for the presence of inflammatory cells, angiogenesis, collagen fibrosis formation, epithelial and fibroblastical proliferation. Basing on the results it was concluded that: 1) CTM and PRP in its two therapeutic fractions association (GCTM+PRPLIQ and GCTM+PRPGEL) did not accelerate the healing process of acute skin wounds, on morphometric assessment at 14 days after surgery; 2) local injection of CTM and PRP fractions when isolated did not accelerate the time required for wound healing on morphometric assessment at 14 days after surgery; 3) PRP application on its liquid fraction showed lower levels of epithelization related to control on histopathological evaluation at 14 days after surgery; 4) except GPRPLIQ, other treatments did not alter significantly inflammatory, proliferative nor initial remodeling phases, based on histopathological data; 5) CTM therapy promoted aesthetically better scars on clinical evaluation, especially at 14 days of observation. It is suggested the requirement of further studies and use of different diagnostic tools to obtain better interpretation of the achieved results.
138

Low-temperature pausing : an alternative short-term preservation method for use in cell therapies

Robinson, Nathalie J. January 2016 (has links)
With encouraging advancements in cell therapies, there is a requirement for an effective short-term cell preservation method, enabling time for quality assurance testing and transport to their clinical destination. This project aims to pause cells at ambient temperatures, whilst maintaining viability and function post-preservation. Ambient cell preservation bypasses ice crystal exposure and toxic solute concentrations experienced with cryogenic storage. Storage in ambient conditions also avoids use of toxic cryoprotectants and aims to greatly reduce costs and reliability on specialist machinery. Early work used HOS TE85 cells (derived from an osteosarcoma) as a model. When atmospheric factors were controlled, HOS TE85 cells demonstrated effective recovery in terms of morphology, membrane integrity (viability >90%) and fold growth expansion when paused at ambient temperature for up to 144 hours. Without atmospheric control, addition of the buffering agent HEPES (25mM) to cell medium was required to keep viability above 70%, as well as to maintain yield and continual passage following 144 hours pausing. The pausing potential of therapeutically relevant human mesenchymal stem cells (hMSCs) from three individual donors (M2, M3 and M4) was tested by keeping cells in suspension for up to 72 hours. Using standard medium with the addition of 25mM HEPES, average membrane integrity was maintained above 70%. Following pausing for between 24 72 hours, hMSC attachment efficiency, immunophenotype and tri-lineage differentiation capacity (osteogenesis, adipogenesis and chondrogenesis) remained similar to non-paused cells. Apart from a short lag phase on the first passage, hMSC fold growth expansion level was consistent with the control for all three donors over 3 x 6 day passages. The colony forming unit (CFU) efficiency of paused cells was significantly reduced when compared with non-paused M2 and M4 lines, whilst M3 retained a similar CFU efficiency to its non-paused counterpart. On return to normal culture conditions, hMSCs had comparable metabolic activity rates with non-paused cells for up to 9 hours. Stable pH is vital during pausing and additional antioxidants or apoptotic inhibiters may be required to keep average viability well-above the 70% threshold, set by the US Food and Drug Administration. Collectively, results have been encouraging and show potential for the movement towards using ambient temperature preservation as an option for the short-term storage and transport of cells for therapy.
139

Avaliação do potencial terapêutico do transplante de células-tronco mesenquimais derivadas de tecido adiposo na cardiopatia chagásica crônica experimental. / Avaliação do potencial terapêutico do transplante de células-tronco mesenquimais derivadas de tecido adiposo na cardiopatia chagásica crônica experimental

Ferreira, Ticiana Xavier January 2011 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-09-04T17:11:04Z No. of bitstreams: 1 Ticiana Xavier Ferreira Avaliação do potencial terapeutico do ....pdf: 16365064 bytes, checksum: 9af2a14308bdaa00d28e7b6a6711fc5b (MD5) / Made available in DSpace on 2012-09-04T17:11:04Z (GMT). No. of bitstreams: 1 Ticiana Xavier Ferreira Avaliação do potencial terapeutico do ....pdf: 16365064 bytes, checksum: 9af2a14308bdaa00d28e7b6a6711fc5b (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / A doença de Chagas, causada pelo protozoário Trypanosoma cruzi, é uma das mais importantes causas de insuficiência cardíaca na América. A terapia celular vem sendo investigada como uma possível opção terapêutica para pacientes com doenças cardiovasculares. Neste estudo foram avaliados os efeitos da terapia com célulastronco mesenquimais em um modelo experimental de cardiomiopatia chagásica crônica. Camundongos C57BL/6 foram infectados com 1000 tripomastigotas da cepa Colombiana de T. cruzi e, após seis meses de infecção, foram tratados com célulastronco mesenquimais derivadas de tecido adiposo humano (CTTAs) ou com meio DMEM (controle). Antes e após 1 e 2 meses de tratamento, os animais chagásicos e controles normais foram submetidos à avaliação cardíaca, incluindo eletrocardiograma, ecocardiograma e teste ergoespirométrico. O grupo tratado recebeu duas injeções intraperitoneais de CTTAs (1x106 células / dose), com um mês de intervalo entre as duas doses. Todos os animais foram sacrificados sob anestesia após 2 meses de tratamento, para análise histopatológica do coração. Não foi observada melhora de arritmias e da função cardiovascular no grupo tratado com CTTAs, porém secções de corações de camundongos deste grupo apresentaram uma redução significativa do número de células inflamatórias (p< 0,0001 ) e da área de fibrose (p< 0,01) em comparação com animais chagásicos tratados com DMEM. A dosagem de 22 citocinas séricas dois meses após o tratamento mostrou um aumento da maioria destas citocinas em animais chagásicos crônicos quando comparados aos controles não-infectados, sendo algumas destas moduladas após a terapia celular. Deste modo, conclui-se que as CTTAs foram capazes de reduzir inflamação e fibrose no coração de camundongos cronicamente infectados por T. cruzi, porém não teve efeitos na função cardíaca dois meses após o transplante. / Chagas disease, caused by the protozoan Trypanosoma cruzi, is one of the most important causes of heart failure in America. Cell therapy has been investigated as a possible therapeutic option for patients with cardiovascular diseases. This study evaluated the effects of therapy with mesenchymal stem cells in an experimental model of chronic Chagas cardiomyopathy. C57BL/6 mice were infected with 1000 trypomastigotes of the Colombian strain of T. cruzi and, after six months of infection, were treated with mesenchymal stem cells derived from human adipose tissue (ADSCs) or DMEM (control). Before and after 1 and 2 months of treatment, chagasic mice and normal controls underwent cardiac evaluation including electrocardiogram, echocardiography and cardiopulmonary exercise test. The treated group received two intraperitoneal injections of ADSCs (1x106 cells / dose), with one month interval. All animals were sacrificed under anesthesia after two months of treatment for histopathology analysis of the heart. No improvement was observed for arrhythmias and cardiovascular function in mice treated with ADSCs, but sections of hearts in this group had a significantly reduced number of inflammatory cells (p<0.0001) and area of fibrosis (p<0.01), compared to animals treated with DMEM. The measurement of 22 serum cytokines two months after treatment showed an increase of most of these cytokines in chronic chagasic animals when compared to uninfected controls, and some of which modulated after cell therapy. Thus, we conclude that the ADSCs were able to reduce inflammation and fibrosis in the hearts of mice chronically infected with T. cruzi, but had no effect on cardiac function two months after transplantation.
140

Efeitos da terapia com células tronco mesenquimais em afecções do sistema nervoso de cães / Effects of mesenchymal stem cells therapy in canine nervous system diseases

Monteiro, Bianca Andriolo [UNESP] 04 August 2017 (has links)
Submitted by BIANCA ANDRIOLO MONTEIRO null (bia_andriolo@hotmail.com) on 2017-09-04T17:12:55Z No. of bitstreams: 1 tese_impressão pós.pdf: 1200489 bytes, checksum: d6d576511877e132bd55c9b142323dcf (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-09-06T12:51:59Z (GMT) No. of bitstreams: 1 monteiro_ba_dr_bot.pdf: 1200489 bytes, checksum: d6d576511877e132bd55c9b142323dcf (MD5) / Made available in DSpace on 2017-09-06T12:51:59Z (GMT). No. of bitstreams: 1 monteiro_ba_dr_bot.pdf: 1200489 bytes, checksum: d6d576511877e132bd55c9b142323dcf (MD5) Previous issue date: 2017-08-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trauma raquimedular, a discopatia e a cinomose são distúrbios que se caracterizam por sinais neurológicos, os quais muitas vezes são de difícil tratamento. Nesse contexto, a terapia celular busca minimizar os sinais e as sequelas neurológicas adquiridas pelas afecções, com objetivo de melhorar a qualidade de vida dos pacientes. Desta forma, o objetivo deste trabalho foi avaliar o resultado do tratamento com células tronco mesenquimais de tecido adiposo nas afecções de trauma rquimedular, sequela de cinomose e discopatia de cães atendidos no serviço de Acupuntura e Dor Crônica da FMVZ-UNESP. Foram utilizados 62 animais, sendo 14 com trauma raquimedular, 17 com discopatias e 31 com sequela de cinomose, todos submetidos ao exame neurológico prévio seguido de terapia celular. A comparação entre os graus antes e após o tratamento com CTMs alogênicas de tecido adiposo para cada tipo de lesão foi realizada utilizando o teste de Mann-Whitney para medidas repetidas. Foi observada diferença entre as medianas referentes ao grau de gravidade das enfermidades tratadas. Nos casos de sequela de cinomose 43.3% (13/30) dos animais tratados apresentaram diminuição dos sinais neurológicos com melhora da graduação da doença. Nos animais com trauma raquimedulares a melhora foi observada em 50% (7/14), e 66.7% dos animais (12/18) que apresentavam discopatias tiveram uma melhora de quadro clínico. Concluiu-se que as aplicações de células tronco mesenquimais em animais com distúrbios neurológicos da lesão da medula espinhal, doença do disco intervertebral e sequelas de cinomorfose diminuíram o grau de lesão das demais afecções. / Spinal cord injury, intervertebral disc disease and distemper are disorders characterized by neurological signs, which are often difficult to treat. In this context, cell therapy seeks to minimize the signs and the neurological sequelae acquired by injuries, aiming to improve the patients' quality of life. Thus, the aim of this study was to evaluate the results of treatment with mesenchymal stem cells of adipose tissue in conditions of spinal cord injury, distemper sequelae and intervertebral disc disease of dogs treated at the Acupuncture and Chronic Pain Service of FMVZ-UNESP. Sixty-two animals were used, 14 of them with spinal cord injury, 18 with intervertebral disc disease and 30 with distempersequelae, all submitted to previous neurological examination followed by cell therapy. A comparison between grades before and after treatment with allogenic adipose tissue MSCs for each type of injury was performed using the Mann-Whitney test for repeated measurements. A difference was observed between to the injury degree of the diseases treated. In the case of distemper, 43.3% (13/30) of the treated animals showed decreased neurological signs with a reduction in the injury degree. In animals with spinal cord injury was observed decrease in 50% (7/14) of injury degree, and 66.7% of the intervertebral disc disease animals (12/18) had a reduced injury degree. It can be concluded that mesenchymal stem cells in animals with nervous system injuries, it covers a medical clinic of second-hand products with neurological disorders of spindle trauma, discopathy and sequelae of distemper. It was concluded that the MSCs applications in animals with neurological disorders of spinal cord injury, intervertebral disc disease and distemper sequelae decreased the injury degree of the diseases treated.

Page generated in 0.0607 seconds