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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.
101

Crescimento e esporulação de Alternaria dauci e A. solani em meio de cultura / Growth and sporulation of Alternaria dauci e Alternaria solani in culture media

Pablo Pulz 16 March 2007 (has links)
Alternaria dauci e A. solani são duas espécies de fungos fitopatogênicos reconhecidamente difíceis de esporular em meio de cultura. Isto dificulta as inoculações artificiais e, conseqüentemente, prejudica o processo de seleção de genótipos de cenoura e tomate resistentes às doenças causadas por estes fungos. Este trabalho teve o objetivo de verificar a influência de alguns fatores, aplicados na incubação, sobre o crescimento micelial e esporulação das duas espécies fúngicas. Diferentes meios de cultura (BDA, aveia e V8), temperatura (15, 20, 25, 30 e 35 °C), comprimentos de onda da luz usada na incubação (amarela, azul, branca, NUV, verde e vermelha), tipos de estresse aplicado à colônia (raspagem, UV, irradiação de microondas e temperatura de 100 °C) e fotoperíodos (luz / escuro, respectivamente, de 24 h / 0 h, 22 h / 2 h, 17 h / 7 h, 12 h / 12 h, 7 h / 17 h, 2 h / 22 e 0 h / 24 h) foram testados. Após a determinação dos melhores fatores, o método desenvolvido neste trabalho foi comparado ao método tradicionalmente utilizado (BDA, 25 °C, 12 h luz branca / 12 h escuro e raspagem da colônia), utilizando diversos isolados de ambas as espécies. Os resultados indicaram o meio V8-ágar e a temperatura de 25 °C como os mais favoráveis ao crescimento e esporulação. Os diferentes comprimentos de onda utilizados tiveram influência marcante na esporulação, sendo o NUV o mais estimulante. Todos os tipos de estresse aplicados induziram esporulação, porém, a raspagem das colônias proporcionou os melhores resultados. O fotoperíodo 12 h luz NUV / 12 h escuro foi o que mais estimulou a esporulação. Observou-se que, de modo geral, períodos de escuro maiores que os períodos de luz aplicados após o estresse da colônia, favoreceram a esporulação. Dessa forma, o processo desenvolvido neste trabalho consistiu de incubação em meio V8-ágar, temperatura de 25 °C, raspagem da colônia e fotoperíodo de 12 h luz NUV / 12 h escuro. Este procedimento mostrou-se nitidamente superior ao tradicionalmente utilizado para crescimento e esporulação de ambas as espécies. / Alternaria dauci e Alternaria solani are two phytopathogenic fungus species known for difficult sporulation in culture media. This hampers artificial inoculations and, consequently, affects the selection process of carrot and tomato genotypes resistant to the diseases caused by these fungi. This study had the objective of verifying the influence of some factors applied during incubation on mycelia growth and sporulation of the two fungus species. Different culture media (BDA, oat and V8), temperature (15, 20, 25, 30 and 35 °C), light wavelengths during incubation (yellow, blue, white, NUV, green, and red), stress types applied to the colony (scratching, UV, microwave irradiation, and temperature of 100 °C) and photoperiods (light / dark, respectively, of 24 h / 0 h, 22 h / 2 h, 17 h / 7 h, 12 h / 12 h, 7 h / 17 h, 2 h / 22 h and 0 h / 24 h) were tested. Upon determination of the best factors, the method developed in this study was compared to the traditional procedure (BDA, 25 °C, 12 h white / 12 h dark light and scratching of the colony), with different isolates of both species. Results indicated the V8-agar media and a temperature of 25 °C as most favorable for growth and sporulation. The different wavelengths had a marked influence on sporulation and NUV was the most stimulating. All applied stress types induced sporulation, but best results were obtained with scratching of the colonies. The 12 h light / 12 h dark photoperiod stimulated sporulation most. In general, longer dark than light periods after the stress of the colony favored sporulation. The procedure developed in this study consisted of incubation in V8-agar media, a temperature of 25 °C, scratching of the colony and a 12 h light / 12 h dark photoperiod. This process is clearly superior to the traditional method for growth and sporulation of both species.
102

A prospective randomized study to compare Nidoil and Ovoil cultur oils used to culture human embryos in IVF therapy

Doyo, Kader January 2016 (has links)
Background: Since the initiation of assisted reproduction techniques, several studies has been performed to improve treatment results by development of culture conditions like embryo oil and culture media used. In this study, two embryonic oils from different companies, Nidoil and Ovoil were examined.Method: In this study, 47 human embryos were used. All embryos were donated for research purposes by couples who had been treated at the clinic in Uppsala University Hospital. The embryos were divided into two groups, one group was cultured with Ovoil and the other with Nidoil.Results: There was no difference between the two oils, the embryo quality was the same in both groups.CONCLUSION: The result was expected because both oils had the same composition and purity.
103

A influência de diferentes meios de cultura na geração de células dendríticas para o tratamento imunoterápico de pacientes com leucemia mieloide aguda / The influence of different culture media in generation of dendritic cells for immunotherapeutic treatment of acute myeloid leukemia patients

Simoneti, Gisele da Silva, 1983- 01 April 2013 (has links)
Orientadores: Simone Cristina Olenscki Gilli, Sara Teresinha Olalla Saad / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T07:27:16Z (GMT). No. of bitstreams: 1 Simoneti_GiseledaSilva_M.pdf: 1770601 bytes, checksum: 967e921fb162c153636ac91afdd1f138 (MD5) Previous issue date: 2013 / Resumo: Células dendríticas (DCs) são as principais células apresentadoras de antígeno do sistema imune, capazes de estimular o linfócito T a iniciar resposta imune especifica. Vacinas de DCs vêm sendo utilizadas como forma de tratamento imunoterápico adjuvante para várias neoplasias. Protocolos para geração dessas células têm sido desenvolvidos e o método ideal de produção para uso clínico ainda necessita ser definido. É fundamental a definição de protocolos e reagentes que ofereçam, a partir de células mononucleares do sangue periférico, células dendríticas seguras e funcionais para uso clínico. A suplementação de meios de cultura com soro de origem animal e humano leva á riscos de xenosensibilização e transmissão de doenças. O uso do soro autólogo parece oferecer menos riscos ao paciente, porém a presença de fatores imunossupressores nesse soro poderia interferir na qualidade das DCs produzidas. Vários tipos de meios livres de soro, baseados nas boas práticas de produção - "good manufacture practice" (GMP), têm sido utilizados recentemente e parecem ser uma opção viável. O objetivo desse estudo foi avaliar os resultados da diferenciação, maturação e funcionalidade de DCs de pacientes com LMA, produzidas em meios livres de soro e em meio suplementado com soro autólogo. Concluímos que os meios de cultura livres de soro foram eficientes na produção de DCs para fins imunoterápicos em pacientes com LMA. Em contrapartida, o uso de soro autólogo parece interferir na capacidade funcional das DCs geradas / Abstract: Dendritic cells (DCs) are the main antigen-presenting cells of the immune system, capable of stimulating T lymphocytes to initiate specific immune responses. Vaccines based on DCs have been used as a treatment adjuvant immunotherapy for various malignancies. Protocols for generating these cells have been developed and the optimal method of production for clinical use remains to be defined. There is a great interest in the definition of protocols and reagents providing from peripheral blood mononuclear cells, functional and safe dendritic cells for clinical use. Supplementation of culture media with serum from animal and human leads to reactions due the animal proteins and transmission of disease. The use of autologous serum seems to offer less risk to the patient, but the presence of immunosuppressive factors may affect the quality of the DCs produced. Several types of serum-free media, based on "good manufacture practice" (GMP), have been used recently and seem to be a viable option. The aim of this study was to evaluate the results of the differentiation, maturation and function of DCs from AML patients, generated in serum-free media and media supplemented with autologous serum. We concluded that the serum-free media were efficient in the production of DCs for immunotherapy in AML patients. However, the use of autologous serum appears to interfere with the functional capacity of generated DCs / Mestrado / Biologia Estrutural, Celular, Molecular e do Desenvolvimento / Mestra em Fisiopatologia Médica
104

Crescimento e esporulação de Alternaria dauci e A. solani em meio de cultura / Growth and sporulation of Alternaria dauci e Alternaria solani in culture media

Pulz, Pablo 16 March 2007 (has links)
Alternaria dauci e A. solani são duas espécies de fungos fitopatogênicos reconhecidamente difíceis de esporular em meio de cultura. Isto dificulta as inoculações artificiais e, conseqüentemente, prejudica o processo de seleção de genótipos de cenoura e tomate resistentes às doenças causadas por estes fungos. Este trabalho teve o objetivo de verificar a influência de alguns fatores, aplicados na incubação, sobre o crescimento micelial e esporulação das duas espécies fúngicas. Diferentes meios de cultura (BDA, aveia e V8), temperatura (15, 20, 25, 30 e 35 °C), comprimentos de onda da luz usada na incubação (amarela, azul, branca, NUV, verde e vermelha), tipos de estresse aplicado à colônia (raspagem, UV, irradiação de microondas e temperatura de 100 °C) e fotoperíodos (luz / escuro, respectivamente, de 24 h / 0 h, 22 h / 2 h, 17 h / 7 h, 12 h / 12 h, 7 h / 17 h, 2 h / 22 e 0 h / 24 h) foram testados. Após a determinação dos melhores fatores, o método desenvolvido neste trabalho foi comparado ao método tradicionalmente utilizado (BDA, 25 °C, 12 h luz branca / 12 h escuro e raspagem da colônia), utilizando diversos isolados de ambas as espécies. Os resultados indicaram o meio V8-ágar e a temperatura de 25 °C como os mais favoráveis ao crescimento e esporulação. Os diferentes comprimentos de onda utilizados tiveram influência marcante na esporulação, sendo o NUV o mais estimulante. Todos os tipos de estresse aplicados induziram esporulação, porém, a raspagem das colônias proporcionou os melhores resultados. O fotoperíodo 12 h luz NUV / 12 h escuro foi o que mais estimulou a esporulação. Observou-se que, de modo geral, períodos de escuro maiores que os períodos de luz aplicados após o estresse da colônia, favoreceram a esporulação. Dessa forma, o processo desenvolvido neste trabalho consistiu de incubação em meio V8-ágar, temperatura de 25 °C, raspagem da colônia e fotoperíodo de 12 h luz NUV / 12 h escuro. Este procedimento mostrou-se nitidamente superior ao tradicionalmente utilizado para crescimento e esporulação de ambas as espécies. / Alternaria dauci e Alternaria solani are two phytopathogenic fungus species known for difficult sporulation in culture media. This hampers artificial inoculations and, consequently, affects the selection process of carrot and tomato genotypes resistant to the diseases caused by these fungi. This study had the objective of verifying the influence of some factors applied during incubation on mycelia growth and sporulation of the two fungus species. Different culture media (BDA, oat and V8), temperature (15, 20, 25, 30 and 35 °C), light wavelengths during incubation (yellow, blue, white, NUV, green, and red), stress types applied to the colony (scratching, UV, microwave irradiation, and temperature of 100 °C) and photoperiods (light / dark, respectively, of 24 h / 0 h, 22 h / 2 h, 17 h / 7 h, 12 h / 12 h, 7 h / 17 h, 2 h / 22 h and 0 h / 24 h) were tested. Upon determination of the best factors, the method developed in this study was compared to the traditional procedure (BDA, 25 °C, 12 h white / 12 h dark light and scratching of the colony), with different isolates of both species. Results indicated the V8-agar media and a temperature of 25 °C as most favorable for growth and sporulation. The different wavelengths had a marked influence on sporulation and NUV was the most stimulating. All applied stress types induced sporulation, but best results were obtained with scratching of the colonies. The 12 h light / 12 h dark photoperiod stimulated sporulation most. In general, longer dark than light periods after the stress of the colony favored sporulation. The procedure developed in this study consisted of incubation in V8-agar media, a temperature of 25 °C, scratching of the colony and a 12 h light / 12 h dark photoperiod. This process is clearly superior to the traditional method for growth and sporulation of both species.
105

Studium povrchových úprav borem dopované diamantové elektrody pro voltametrii dopaminu a serotoninu / Study of surface modifications of boron doped diamond electrode for voltammetric detection of dopamine and serotonin

Eremina, Anna January 2021 (has links)
This diploma thesis deals withthe studyof electrochemical behaviorand detection of two structurally different neurotransmitters, dopamine (DA) and serotonin (5-HT), in solutions commonly used for neuron cultivation, namely Neurobasal (NB), NB with phenol red and in phosphate buffer (PB) of a pH close to the physiological value. An electrode based on boron-doped diamondwas used for the study, examiningtwo types of surfaces obtained after oxidation (O-BDD) and mechanical polishing (p-BDD). The results were obtained by two voltametric techniques,namely cyclic and differential pulse voltammetry.The studyrevealedthat DA oxidationis a quasi-reversible process,whereas 5-HT oxidizes irreversibly on O-BDD and p-BDD. Nevertheless, for both neurotransmitters their anodic oxidationonboth BDD surfaces is controlledby diffusion. Due to the passivation of the electrode surface by the oxidation products, anodic reactivation(Eact = +2400 mV, t = 30 s) was first testedto regenerate the O-BDD surface during DA and 5-HT measurements. There was no continuous decrease in DA peak currents on O-BDD and the measuredsignals were characterizedby high repeatabilityin all studiedmedia (sr (Ip) 1.1% in PB of pH 7.0, 1.7% in NB of pH 7.34, 0.9% in NB with phenol red of pH 7.48). In the case of 5-HT, the anodic reactivation was...
106

Effect of in vitro culture media and assisted hatching techniques on mice embryo survival rate following cryopreservation

Serota, Nthabiseng Ruth 18 May 2018 (has links)
MSCAGR (Animal Science) / Department of Animal Science / This study determined the effects of in vitro culture media (Ham’s F10 and TCM199) and assisted hatching techniques (laser or mechanical) on mice embryo survival following cryopreservation. Pure strain C57BL/6 (B6) female (50) and strain BALB /c (C) Male (25) mice were crossed to produce F1 generation of females which were injected for follicular growth and super ovulation at 6 weeks of age and from which embryos were produced 21 h later through in vivo fertilization. Embryos were randomly divided into Petri dishes with different culture media, and the development of embryos was assessed until the morula stage. At the morula stage, selected embryos were assisted to hatch using different techniques, and then cryopreserved in liquid nitrogen using the slow freezing method for a period of 1 week. After 1 week of cryopreservation, the embryos were thawed and cultured in the two different in vitro culture media for 72 hours. Thereafter, the numbers of embryos hatched or survived were recorded after 24 h, 48 h and 72 h. Data was analyzed using ANOVA in Minitab Software Version 16 (2010). Significant difference in embryo quality development was observed between in vitro culture media and stage of embryo development (P<0.05). In the TCM-199 in vitro culture medium, embryo quality development yielded 72, 69 and 69% from day 1 to day 3, while in Ham’s F10 embryo quality development yielded 68, 63 and 60% respectively. Relative to the control (18.1%) assisted hatching improved hatchability significantly (P<0.05) in the order laser (23.6%)>, mechanical (20.8%). There was significant (P<0.01) interaction between assisted hatching techniques and evaluation time, whereby laser assisted hatching was most successful at 48 h (42.0%) while mechanical assisted hatching was most successful at 72 h (36.8%). Cryopreservation reduced the embryo survival compared to fresh embryos. In conclusion laser was the best assisted hatching technique, while TCM-199 was the better medium for in vitro culture of embryo. / NRF
107

Effect of culture conditions, donor source, and injection site on in vitro development of deoxyribonucleic acid microinjected porcine zygotes

Hajdu, Melissa Anne 17 December 2008 (has links)
A series of experiments were used to evaluate three culture media and two incubation temperatures for their ability to support development of DNA microinjected porcine zygotes. Development in vitro was compared between embryos collected from postpubertal and prepubertal donors and between embryos injected with DNA into the pronucleus and the cytoplasm. Additionally, embryos were analyzed by the polymerase chain reaction (PCR) for the presence of the transgene. One-cell embryos (n=458) were recovered from 36 postpubertal gilts in Experiment 1. Injected and control embryos were cultured in modified media NCSU-23 (mNCSU-23), NCSU-37 (mNCSU-37), and CZB at 37°C and 38.8°C for 7 d. In Experiment 2, one-cell embryos (n=245) were collected from postpubertal (n=15) and prepubertal (n=14) gilts, microinjected with DNA, and cultured in medium mNCSU-23. Superovulated prepubertal gilts (n=22) were flushed in Experiment 3 to yield 343 one-cell embryos which had DNA injected into the cytoplasm or pronucleus. Whole embryos were assessed by PCR. Mean percentages of embryos developing to the expanded or hatched blastocyst stage in mNCSU-23 and mNCSU-37 did not differ from each other (p>.05), but both were greater than the development in CZB (p<.05). Development was greater at 38.8°C (p<.05) than at 37° C. Microinjection of DNA decreased the developmental percentage (p<.05) from that of non-injected controls. Embryos collected from postpubertal gilts had a higher percentage (68.0 ± 3.4) of expanded and hatched blastocysts than embryos from prepubertal donors (29.0 ± 4.6, p<.05). No difference was seen in development between embryos injected in the pronucleus or cytoplasm (p>. 05), but development for both was less than for control embryos (p<.05). Results of PCR analysis indicated that 40% of the embryos developing to the expanded blastocyst stage were positive for the transgene compared to a rate of 60% positive for degenerate embryos. These studies show that DNA microinjected porcine zygotes can be cultured to the expanded blastocyst stage in media mNCSU-23 and mNCSU-37 at 38.8°C. Microinjection of DNA decreases survival of embryos collected from both postpubertal and prepubertal sources, but postpubertal embryos exhibit a higher rate of development. Cytoplasmic injection does not improve embryo viability in vitro above that of pronuclear injection. Finally, whole embryo analysis by PCR is possible, but cross specificity of human Protein C and whey acidic protein (WAP) oligonucleotides for endogenous porcine DNA is strong and creates difficulty in applying PCR analysis to embryos microinjected with WAP-PC transgenes. / Master of Science
108

La construction des pratiques informationnelles par le(s) public(s) des médias : trajectoire biographique, parcours de pratique, culture informationnelle médiatique / How do news consumption evolves at the individual level : biographical trajectory, media practice itinerary, news and media culture

Goasdoué, Guillaume 11 December 2012 (has links)
Pourquoi les individus s‟informent et comment en arrivent-ils à consommer certains types d‟actualités et de médias au cours de leur vie ? À partir de ces questionnements nous avons interrogé quarante-six personnes aux profils contrastés pour mettre en parallèle les trajectoires biographiques et les parcours de pratiques informationnelles médiatiques. La première partie traite de la socialisation aux médias en pointant l‟influence de la classe sociale, de la famille,du sexe et du rapport à l‟école et à la lecture. Sont également mis en avant le rôle des études supérieures (durée et filière) et le niveau de politisation. Dans la deuxième partie nous interrogeons la compétence politique, les contextes de consommation et les capacités techniques. Un développement est spécialement consacré à l‟incidence d‟une « culture informationnelle médiatique » dans le processus individuel d‟appropriation des actualités. Ce travail contribue également aux réflexions méthodologiques qui concernent l‟étude des publics des médias, de la politisation et des usages des technologies de l‟information et de la communication (TIC). Les résultats invitent à appréhender le niveau d‟instruction et la position sociale comme les principaux facteurs explicatifs des comportements informationnels. / How do people get informed and are brought to pay attention to news and how do they go about consuming different types of news and media during their lives? With these questionsin mind we interviewed forty six individuals with various and diverse profiles so as to try tocompare their media practice itineraries. The first part focuses on socialization and media,particularly on what influences news consumption: social class, gender, family structure, and personal experience of schooling and reading. We also try to focus on the role of superior studies (field and duration) and the level of political awareness. In the second part we willfurther develop the various aspects of political sophistication, context of consumption(situation), and knowledge of technologies. One section is specifically dedicated to theconcept of "media information culture" in the individual process of appropriation of the news.This work also contributes to the methodological reflection regarding the study of media audiences, politics and use of information and communication technologies (ICT). The results invite to consider the level of education and social situation as primary factors explaining information and news consumption related behaviors.
109

Avaliação inflamatória do uso de células tronco mesenquimais em modelo animal de doador de pulmão com choque hipovolêmico / Inflammatory evaluation of the use of mesenchymal stem cells in animal model of a lung donor with hypovolemic shock

Dias, Vinicius Luderer 31 May 2019 (has links)
espera por transplante pulmonar. A baixa taxa de aproveitamento do pulmão nas captações de órgãos figura como questão de destaque. Como causas, listamos a rigidez nos critérios de seleção, vulnerabilidade do órgão, cuidados inadequados com os pacientes em morte encefálica, edema pulmonar neurogênico pela morte encefálica e trauma com choque hemorrágico, que leva à hipoperfusão dos pulmões, acidose metabólica e inflamação tecidual. Morte encefálica e choque representam importantes causas de deterioração pulmonar, levando à recusa do órgão na captação ou à disfunção primária do enxerto pós-transplante. Na tentativa de melhorar a condição do enxerto pulmonar para se obter maior número de pulmões viáveis para o transplante, e para reduzir os índices de rejeição, algumas estratégias foram adotadas pelas equipes transplantadoras. O uso de células tronco mesenquimais (Mesenchymal Stem Cells - MSCs) para tratamento de afecções inflamatórias é objeto de estudo de alguns grupos, dadas as propriedades anti-inflamatórias e imunomodulatórias já conhecidas. Nossa hipótese baseia-se na realização de tratamento com MSCs ou seus fatores solúveis (FS-MSCs) em doadores com choque hemorrágico. O objetivo deste trabalho é avaliar inflamação pulmonar em ratos, após o tratamento do choque hemorrágico com reposição sanguínea, associada à infusão in vivo de MSCs ou FS-MSCs. Quarenta e oito ratos foram divididos em 4 grupos: Sham (Sham n=12); Choque (Choque n=12); FS (Choque + FS-MSCs n=12) e MSC (Choque + MSCs n=12). Após anestesia, os animais foram submetidos à cateterização da artéria e veia femoral para registro de pressão arterial média (PAM), indução de choque hemorrágico e infusão de MSCs ou FS-MSC nos grupos de tratamento. No grupo Sham foi realizada apenas a monitorização dos parâmetros hemodinâmicos. Nos grupos Choque, FS e MSC foi realizado o choque hemorrágico (40 mmHg), e tratamento com FS-MSCs (1ml de secretoma em dose única) no grupo FS ou MSCs humanas (1x107células em dose única) no grupo MSC. Após 190 minutos, o experimento foi finalizado e o bloco pulmonar extraído. Foram analisadas: a histopatologia do tecido pulmonar e a concentração de marcadores inflamatórios (Tnf-alfa, IL1-beta, IL-6, IL-10, iCAM e vCAM) no lavado broncoalveolar e no tecido pulmonar. Na análise histológica a densidade de neutrófilos apresentou diferença estatística significante com o grupo FS apresentando a menor densidade quando comparado aos grupos Choque e MSC (p < 0,001). A dosagem de IL-10 no grupo FS foi superior aos demais grupos (p=0,044). Concluímos que os pulmões de ratos submetidos ao choque hemorrágico tratados com FS-MSCs apresentam redução de inflamação pela redução do infiltrado neutrofílico / Many factors are responsible for the large number of patients on waiting list for a lung transplant. The low rate of lung utilization in organ uptakes appears as a critical issue. As causes, we highlight the rigorous selection criteria, organ vulnerability, inadequate care for patients in brain death, neurogenic pulmonary edema due to brain death and trauma with hemorrhagic shock, that leads to hypoperfusion of the lungs, metabolic acidosis and tissue inflammation. Brain death and shock represents important causes of pulmonary deterioration, leading to organ rejection at the uptake or primary graft dysfunction in post-transplantation. To improve the pulmonary graft condition in order to obtain a larger number of viable lungs for transplantation and to reduce rejection rates, some strategies were adopted by transplantation teams. The use of mesenchymal stem cells (MSCs) for treatment of inflammatory conditions is the object of study of many groups, due to the anti-inflammatory and immunomodulatory properties of these cells previously described. Our hypothesis is based on treatment with MSCs or their soluble factors (FS-MSCs) in donors with hemorrhagic shock. The aim of this work is to evaluate pulmonary inflammation in rats, after hemorrhagic shock treatment with blood replacement, associated with in vivo infusion of MSCs or FS-MSCs. Forty-eight rats were divided into 4 groups: Sham (Sham n = 12); Shock (Shock n = 12); FS (Shock + FS-MSCs n = 12) and MSC (Shock + MSCs n = 12). After anesthesia, animals were submitted to femoral artery and vein catheterization for monitoring of mean arterial pressure (MAP), induction of hemorrhagic shock and MSCs or FS-MSC infusion in treatment groups. At Sham group, only hemodynamic parameters were monitored. Hemorrhagic shock (40 mmHg) was performed in Shock, FS and MSC groups, and treatment with FS-MSCs (1ml secretome in single dose) were performed in the FS group or human MSCs (1x107 cells in single dose) in the MSC group. After 190 minutes, the experiment was terminated and the lung block was removed. The histopathology of lung tissue and the concentration of inflammatory markers (Tnf-alpha, IL-1Beta, IL-6, IL-10, ICAM and vCAM) in the bronchoalveolar lavage fluid and tissue were analyzed. In histological analysis, the neutrophil density showed a statistically significant difference with FS group presenting the lowest density when compared to Shock and MSC groups (p < 0.001). IL-10 dosage in FS group was higher than all other groups (p = 0.044). We conclude that the lungs of rats submitted to hemorrhagic shock treated with FS-MSCs present reduction of inflammation by the reduction of neutrophilic infiltrate
110

Caractérisation des cellules souches gingivales et protocole de culture préclinique pour une thérapie osseuse humaine / Characterization of human gingival stem cells and preclinical culture protocol for human bone therapy

Taïhi, Ihsène 04 December 2017 (has links)
La thérapie cellulaire est une méthode d’avenir innovante, actuellement utilisée dans le traitement de pathologies multiples (auto-immunitaire, cancéreuses, pathologies inflammatoires, allogreffes…) et la régénération des pertes de substance tissulaire. Les cellules souches mésenchymateuses, par la variabilité de leurs origines, présentent des propriétés très intéressantes à la thérapie, notamment un potentiel de différenciation en lignées multiples, et des propriétés d’immunomodulation importantes. Mon projet s’intéresse à l’utilisation de cellules souches orales récemment isolées de la gencive par notre équipe : cellules souches gingivales (GSC), et présentant un avantage fonctionnel par rapport aux sources cellulaires traditionnelles d’origine mésodermique (moelle osseuse) ou orales (pulpe dentaire, follicule dentaire, ligament parodontal, glandes salivaires…). Les défauts osseux des mâchoires, de par leur multitude d’étiologies (traumatismes, dysmorphoses, cancer, ...) et le handicap généré, représentent une cible thérapeutique privilégiée. Les GSCs ont la même origine embryologique neurectodermique que les os maxillaires et par là-même un phénotype proche, exploré dans notre équipe. Cette source gingivale de prélèvement non traumatique est une alternative aux techniques chirurgicales actuelles mutilantes pour le site donneur. Notre objectif est double : Etablir un protocole préclinique de culture des GSC en ostéoblastes, pour être compatibles avec la thérapie humaine afin d’obtenir une régénération osseuse optimale. Les capacités immunomodulatrices des GSCs sont par là-même étudiées dans ces nouvelles conditions, dans le but de maitriser la réaction inflammatoire et préserver la greffe osseuse, grâce à la plateforme exceptionnelle mise à notre disposition par l’établissement français du sang, et une équipe très spécialisée dans l’étude des mécanismes de régulation immunitaires. Nos résultats permettront non seulement une régénération osseuse transposable chez l’homme, mais également d’utiliser ces cellules pour le traitement d’autres pathologies (cancéreuses, auto-immunitaires…) en utilisant leur capacité immunomodulatrice. / Cell therapy is an innovative method of the future, currently used in the treatment of multiple diseases (autoimmune, cancer, inflammatory pathologies, allografts ...) and the regeneration of tissue loss. Mesenchymal stem cells (MSC), regardless their origins, exhibit very interesting properties for therapy, including a potential for multi-line differentiation, and important immunomodulation properties. My project focuses on the use of oral stem cells recently isolated from the gingiva by our team (GSC), and having a functional advantage over traditional mesodermal (bone marrow) cellular sources. The bone defects of the jaws, due to their multitude of etiologies (trauma, dysmorphoses, cancer...) and the generated handicap, represent a preferred therapeutic target. GSCs have the same neurectodermal embryological origin as the maxillary bones and thus a similar phenotype, explored in our team. This gingival source of non-traumatic removal is an alternative to current mutilating surgical techniques for the donor site. Our goal is twofold: To establish a preclinical GSC culture protocol in osteoblasts, to be compatible with human therapy, in order to achieve optimal bone regeneration. The immunomodulatory capacities of the GSCs are themselves studied under these new conditions, with the aim of controlling the inflammatory reaction and preserving the bone graft, thanks to the exceptional platform made available to us by the French blood establishment, and A highly specialized team in the study of immune regulation mechanisms. Our results will not only allow transposable bone regeneration in humans but also use these cells for the treatment of other pathologies (cancerous, autoimmune ...) using their immunomodulatory capacity.

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