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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.
261

Evaluation of 5´- and 3´-UTR Translation Enhancing Sequences to Improve Translation of Proteins in CHO Cells

Einarsson, Ellen January 2018 (has links)
The purpose of this project was to identify and evaluate nucleotide sequences enhancing translation of proteins in Chinese hamster ovary (CHO) cells. Candidate sequences were placed in the 5´-untranslated region (UTR) or 3´ UTR respectively and evaluated in a CHO-based expression system with a fluorescent Fc-fusion protein as a model protein.Five plasmid vectors were constructed, two of which designed to have a randomized nucleotide library in their 5´ and 3´ UTR respectively, and three of which designed to hold varying repeats of a known enhancing translation (ET) sequence in their 5´ or 3´ UTR. The plasmid constructs were transfected into CHO cells and the protein expression was analyzed both by fluorescence intensity in single cells using flow cytometry and in bulk by monoclonal antibody titer analysis based on Protein A affinity.The main result is that both flow cytometry and titer analysis indicate that insertion of five repeats of the ET in the 5´UTR has a negative effect on protein expression as compared to the control which had no ET repeats. Results related to the insertion of three ETs in the 5´ UTR were ambiguous. The titer analysis indicated that it had a negative effect on the protein expression compared to the control which had no ET repeats, whereas the flow cytometry results suggest that the effect is negligible. Transfection of library plasmids was unsuccessful; hence no library expression analysis results were achieved. Due to the time constraints of the project, the reason for the unsuccessful transfection of library plasmids was not investigated, but the LTX transfection method is stated as a highly plausible cause.Based on the outcome of this study, two recommendations for future work are suggested. The first one is to continue the focus on UTR sequences in terms of library screening, and to improve the method of transfecting library plasmid constructs into CHO cells using lipofection. The second suggestion for further studies is to test different UTR sequence lengths without involving potential ETs, to rule out the effect and positions of the ETs and investigate the expressional effect of UTR length solely.
262

Biosystematic revision of the Spergularia echinosperma complex

KÚR, Pavel January 2017 (has links)
This thesis is focused on the biosystematic study of the Central-European endemic Spergularia echinosperma. With the combined use of morphometric analyses, genome size measurements and molecular tools, the taxonomic issues associated with this species have been clarified. The existence of S. kurkae, a stable allotetraploid hybrid between diploid S. echinosperma and tetraploid S. rubra, has been proven. Based on several lines of evidence, including distinct morphological separation and frequent occurrence in the absence of the parental species, treating S. kurkae as a separate species is proposed. In addition, two infraspecific taxa within S. echinospermaS. echinosperma subsp. echinosperma and S. echinosperma subsp. albensisdiffering in distributions and ecology have been described. A complete revision of the localities of S. echinosperma, S. kurkae and S. rubra in the Czech Republic is also presented. Furthermore, the development of 16 polymorphic microsatellite loci for S. echinosperma is reported.
263

ABVIC: A NOVEL FLOW CYTOMETRY-BASED ASSAY FOR THE DETECTION OF HSV-SPECIFIC ANTIBODIES

Sowa, Gavin Michael 01 December 2016 (has links)
Herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) are closely related viruses that establish lifelong infection in their hosts and can periodically reactivate to cause painful lesions. Approximately 50 million Americans are infected with HSV-2, the primary cause of genital ulcerative disease. In addition to the pain of the physical symptoms, genital herpes is highly stigmatized and can cause significant reductions in quality of life. HSV-2 has been demonstrated to have a synergistic relationship with HIV, where it enhances the transmissibility, susceptibility and severity of disease. In addition, potentially life-threatening neonatal herpes occurs in about 1 in 10,000 live births. While there are known means of reducing the risk of transmission, the overwhelming majority of infected persons are unaware of their status, and they remain the driving force behind new infections. Virological tests, such as PCR, are ill suited for asymptomatic infections since the detectable virus is only shed on <10% of days. Currently available type-specific serological tests based on glycoprotein G are prone to false-positive results, lack the sensitivity to detect new infections and may be affected by cross-reactivity between HSV-1 and HSV-2. Due to the known limitations of HSV serological testing, it is not recommended for the general population or pregnant women. In the first half of my thesis, I evaluate a new flow-cytometry-based method that measures serum antibody-binding to virus-infected cells (ABVIC). We obtained a panel of human control sera from Westover Heights Clinic (WHC) and determined if the ABVIC could measure HSV-specific antibody binding to test-cells. We found that the assay was sensitive, semi-quantitative, and could be made type-specific with the addition of a pre-adsorption step. The ABVIC offers an advantage over the standard of care single-antigen tests as the result measuring antibody binding to all viral proteins fixed in their native conformation. In the second half of my thesis, I used the ABVIC assay test n=34 blinded test-sera. Of these, n=17 had previously tested as “indeterminate” by bother Herpeselect ELISA as well as Western Blot. Following unblinding, we found that the ABVIC properly identified all n=17 patient sera of an unambiguous serostatus. Of the indeterminate sera, all were found to be seronegative for HSV-2. Based on these surprising results, we requested an additional n=11 indeterminate samples, which were also found to be HSV-2 seronegative. Most of the "Indeterminate" serum samples exhibited high background, which produced weak reactivity in HerpeSelect and Western blot assays, but did not confound the internally controlled ABVIC test.
264

Avaliação da apoptose nas populações leucocitárias do sangue periférico de pacientes sépticos / Evaluation of apoptosis in leukocytes populations of the peripheral blood of septic patients

Martos, Leandro Silva Willish [UNIFESP] 18 March 2010 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:49:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-18. Added 1 bitstream(s) on 2015-08-11T03:26:15Z : No. of bitstreams: 1 Publico-12957a.pdf: 1243731 bytes, checksum: 878db06d2872246e99cbd4358ee4a1d0 (MD5). Added 1 bitstream(s) on 2015-08-11T03:26:15Z : No. of bitstreams: 2 Publico-12957a.pdf: 1243731 bytes, checksum: 878db06d2872246e99cbd4358ee4a1d0 (MD5) Publico-12957b.pdf: 1376768 bytes, checksum: 4cdb6afbfd0e66e1d0fb5c0615f48744 (MD5) / A sepse apresenta crescente incidência com elevada morbidade e mortalidade, sendo a principal causa de óbito nas unidades de terapia intensiva. O controle da infecção depende do adequado reconhecimento dos microrganismos pelas células do hospedeiro e de resposta efetora competente. Os linfócitos, monócitos e neutrófilos são as principais populações celulares do sangue periférico envolvidas nesse processo. A apoptose representa um importante mecanismo de controle da resposta imune, mas em condições críticas, a apoptose desregulada dessas células pode levar o hospedeiro a imunossupressão, dificultando o controle da sepse. Este trabalho avaliou-se a porcentagem de apoptose em linfócitos monócitos e neutrófilos do sangue periférico de pacientes sépticos pela exposição de fosfatidilserina na superfície celular e pela detecção intracelular de caspase-3, também foi avaliado o número absoluto e percentual de linfócitos e suas subpopulações por citometria de fluxo. Foram incluídos 40 pacientes, sendo 4 em sepse, 9 em sepse grave e 27 em choque séptico, classificados de acordo com as definições do consenso de 1992. Quinze voluntários sadios foram incluídos para comparação. Nos ensaios de detecção de apoptose foi feita a separação dos leucócitos totais seguida de lise hipotônica das hemácias e marcação com anticorpos de superfície para identificação das populações leucocitarias. Para verificação da apoptose as amostras foram marcadas com anexina-V e coradas com Iodeto de Propídeo (PI) em tampão apropriado ou incubadas com anticorpo anti-caspase-3 após fixação e permeabilização. A contagem de linfócitos foi realizada em tubos TruCOUNT após a marcação com anticorpos anti-CD45, CD3, CD4, CD8, CD16/56 e CD19. Não houve diferença no percentual de linfócitos totais em apoptose, porém observou-se menor apoptose tardia em linfócitos T nos pacientes sépticos quando comparados aos sadios ( P<0,05). Foi observada menor contagem absoluta de linfócitos totais, linfócitos T, TCD4+, TCD8+ e NK de pacientes sépticos (p<0,01), embora o percentual destas populações celulares tenha se mantido inalterado. Os resultados mostram que o menor número de linfócitos circulantes observados durante o quadro de sepse não pôde ser explicado pela presença de apoptose. A diminuição da contagem destas células na periferia pode significar uma migração para os tecidos ou órgãos linfóides desencadeada pela infecção. Nos neutrófilos não foi observada diferença no percentual de células em apoptose precoce entre pacientes e indivíduos sadios. Houve queda no percentual de apoptose tardia e conseqüente aumento no percentual de células viáveis dos pacientes em comparação aos sadios (p<0,05). Não se observou diferença significativa na mensuração intracelular de caspase 3 em neutrófilos de pacientes comparado a indivíduos sadios. A análise da apoptose durante a evolução da sepse não mostrou diferença entre os grupos D0, D7 e D14. Não houve diferença na proporção de células em apoptose entre pacientes com sepse que sobreviveram e pacientes que evoluíram a óbito até o vigésimo oitavo dia após o diagnóstico de sepse. A apoptose tardia em neutrófilos parece estar diminuída. O possível efeito biológico da redução de apoptose tardia seria uma resposta adaptada à lesão, talvez prolongando a meia vida e atividade dos neutrófilos, entretanto, essa apoptose diminuída pode contribuir para a lesão inflamatória sistêmica e predispor o desenvolvimento da síndrome de disfunção de múltiplos órgãos. Os monócitos foram avaliados unicamente pela detecção intracelular de caspase-3, todavia, não foi encontrado diferença entre pacientes sépticos e indivíduos sadios. O mesmo ocorreu em amostras obtidas na admissão, 7º e 14º dia de seguimento. O percentual de monócitos com positividade para caspase-3 nos dias 0, 7 e 14 de sepse foi relacionado com a evolução dos pacientes em sobreviventes e óbitos, após 28 dias do diagnóstico. A análise realizada com amostras do D0 não indicou diferença na porcentagem de células apoptóticas entre os pacientes sobreviventes e que evoluíram a óbito. Entretanto, o percentual de apoptose observado no D7 mostrou que pacientes que evoluíram a óbito apresentaram menor porcentagem de células positivas para caspase-3 após 28 dias, e essa associação persistiu no seguimento de 60 e 180 dias. O papel da apoptose em monócitos parece ser muito importante na sepse, todavia são necessários novos estudos para elucidar a correlação entre apoptose de monócitos e sobrevida. / Sepsis incidence continues to rise with significant morbidity and mortality and is the leading cause of death in intensive care units. Infection control depends on proper recognition of the microorganisms by immune cells and an adequade effector immune response. Lymphocytes, monocytes and neutrophils are the major peripheral blood cell populations involved in this process. Apoptosis is an important mechanism for controlling the immune response, however, in critical conditions, deregulated apoptosis can lead to immune suppression, difficulting the control of sepsis. This study evaluated the percentage of apoptosis in peripheral blood derived lymphocytes, monocytes and neutrophils by means of exposure of phosphatidylserine on the cell surface and detection of intracellular caspase-3 and evaluated the absolute number and percentage of lymphocytes and their subpopulations by flow cytometry. Forty septic patients were included, of whom, 4 were septic, 9 presented severe sepsis and 27 were in septic shock, classified according to the definitions of the 1992´s consensus. Fifteen healthy volunteers’ were included for comparison. For apoptosis assays, total leucocytes were isolated from the whole blood by hypotonic lysis of the red blood cells and stained with surface antibodies in order to identify the leukocyte subpopulations. For apoptosis evaluation samples were stained with annexin-V and propidium iodide (PI) in an appropriate buffer or labeled with anti-caspase-3 after fixation and permeabilization. Lymphocyte counts were performed in TruCOUNT tubes after labeling the cells with anti-CD45, CD3, CD4, CD8, CD16/56 and CD19. There were no statistical differences in the percentage of apoptosis in total leukocytes, however, lower late apoptosis was observed in T lymphocytes of septic patients when compared to healthy subjects (P<0.05). Septic patients showed a smaller absolute count of total lymphocytes, T lymphocytes, CD4+, CD8+ and NK cells when compared to the healthy individuals (P<0.01), although the percentage of these cell populations has remained unchanged. These results demonstrate that the smallest number of circulating lymphocytes observed during sepsis could not be explained by the presence of apoptosis. The decrease of peripheral blood cell counts could be a result of the cell migration to the lymphoid tissues or organs triggered by infection. There were no differences in the percentage of early apoptosis in neutrophils of patients and healthy individuals. There was a decrease in the percentage of late apoptosis and a consequent increase in the percentage of viable cells in the patients when compared to the healthy subjects (P<0.05). There was no significant differences in the measurement of intracellular caspase-3 in neutrophils of patients compared to the healthy individuals. Analysis of apoptosis during the development os sepsis did not differ among the D0, D7 an D14 groups. There was no difference in the proportion of cells undergoing apoptosis between patients with sepsis who survived and those who died by the twenty-eight (D28) after the diagnosis of sepsis. Late apoptosis in neutrophils appears to be diminished. The possible biological effect of the reduction of apoptosis would be an adapted response to the injury, perhaps extending the half life and activity of neutrophils, however, this decreased apoptosis may contibute to inflammatory injury and predispose to the development of the multiple organ dysfunction syndrome. Only intracellular caspase-3 was evaluated in monocyte population, and no differences were found between this marker on septic patients and healthy individuals. The same results were observed in samples from adminssion, 7 and 14 days of follow-up. The percentage of monocytes with caspase-3 activity on days 0, 7 and 14 of sepsis was related to patient outcome as regards of survival and non-survival, after 28 days of diagnosis. The analysis performed on samples from D0 did not indicate differences in the percentage of apoptotic cells among the survivors and non-survivors. To counterpoint, when this analysis was performed on D7, the percentage of cells positive for caspase-3 were lower in those who died when compared with the survivors after 28 days; besides, this association persisted on 60 and 180 days follow-up. The role of apoptosis in monocytes seems to be important in sepsis, however, further research is needed to elucidate the correlation between monocyte apoptosis and survival. / TEDE
265

Avaliação ex vivo da proliferação espontânea em PBMC de indivíduos infectados pelo HTLV-1 por citometria de fluxo / Avaliação ex vivo da proliferação espontânea em PBMC de indivíduos infectados pelo HTLV-1 por citometria de fluxo

Pinto, Lorena Ana January 2010 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-07-23T21:20:51Z No. of bitstreams: 1 Lorena Pinto. Avaliação ex vivo da proliferação espontanea em PBMC de individuos infectados pelo HTLV-1 por citometria de fluxo.pdf: 1267124 bytes, checksum: 830b004821bb96ca261aed15410bcb82 (MD5) / Made available in DSpace on 2012-07-23T21:20:51Z (GMT). No. of bitstreams: 1 Lorena Pinto. Avaliação ex vivo da proliferação espontanea em PBMC de individuos infectados pelo HTLV-1 por citometria de fluxo.pdf: 1267124 bytes, checksum: 830b004821bb96ca261aed15410bcb82 (MD5) Previous issue date: 2010 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / O vírus linfotrópico de células T humanas do tipo 1 (HTLV-1) infecta cerca de 2% da população de Salvador-Bahia. O HTLV-1 é o agente etiológico da ATLL, HAM/TSP e uveíte. Este vírus também está relacionado a outras doenças inflamatórias como artrites, dermatites infectivas, polimiosites, alveolites e Síndrome de Sjögren. Uma das características imunológicas mais marcantes da infecção pelo HTLV-1 é a proliferação espontânea dos linfócitos T induzida por proteínas transativadoras virais, como Tax e HBZ. O papel da proliferação na patogênese da infecção não é conhecido, porém alguns trabalhos indicam que sua intensidade é maior nos pacientes com HAM/TSP, além disso pode ser responsável pela manutenção da carga proviral do HTLV-1, uma vez que o vírus se replica por divisão da célula infectada. A dinâmica da proliferação ex vivo não é muito conhecida, sendo normalmente avaliada por adição de 3[H]-Timidina às culturas, que possui várias desvantagens, entre as quais a toxicidade. Este é um estudo piloto que objetivou padronizar um método para avaliação da dinâmica da proliferação espontânea de linfócitos T utilizando o marcador CarboxyFluorescein diacetate Succinimidyl Ester (CFSE), por citometria de fluxo. Além de quantificar os índices de proliferação celular de linfócitos T totais e das subpopulações linfocitárias T CD4+ e T CD8+, correlacionar proliferação celular com a carga proviral do HTLV-1 e a expressão da proteína viral TAX. Para tal, PBMC de 30 pacientes infectados pelo HTLV-1 (16 assintomáticos e 14 HAM/TSP) foram cultivados por 24, 48, 72, 96 e 120 horas, em presença de CFSE. As células foram adquiridas em citometro de fluxo e os resultados analisados pelo programa FlowJo, através da porcentagem de células divididas e do índice de divisão celular. Observou-se proliferação em 66,7% dos indivíduos infectados pelo HTLV-1. A proliferação espontânea de PBMC foi superior no grupo de pacientes com HAM/TSP (porcentagem de células divididas: 79%, índice de divisão celular: 79%), comparada aos assintomáticos (porcentagem de células divididas: 50%, índice de divisão celular: 56,3%), porém essa diferença não foi significante A proliferação espontânea pode ser detectada nas primeiras 24 horas de cultura. A intensidade de proliferação é semelhante para as subpopulações de linfócitos T CD4 e T CD8, tanto em indivíduos assintomáticos como naqueles com HAM/TSP. Não houve correlação entre a carga proviral e a porcentagem de células divididas (r= -0,009; p= 0,9) e índice de divisão celular (r=0,1; p=0,5). A média de expressão de TAX em linfócitos TCD4+ foi de 2,4±2,4 %. Houve correlação entre a expressão da proteína Tax e a porcentagem de células divididas (r=0,59; p =0,05) e o índice de divisão celular (r=0,60; p=0,05), porém sem significância estatística. No entanto, encontrou-se uma correlação positiva entre a porcentagem de células T CD4+ divididas e a expressão da proteína Tax (r=0,79; p<0,003), bem como entre o índice de divisão das células TCD4+ e a expressão da proteína Tax (r=0,75; p=0,008). Em conclusão, a avaliação da proliferação espontânea por citometria de fluxo, em culturas com CFSE avaliadas pelo programa FlowJo permite identificar a proliferação celular nas 24 horas inicias da cultura e quantificar a proporção de linfócitos T CD4 e TCD8 que proliferam. Este método pode ser útil na avaliação de drogas que modulam a proliferação espontânea em PBMC de indivíduos infectados pelo HTLV-1. / Around 2% of the population of Salvador-Bahia are infected by the Human-T Lymphocyte virus type I (HTLV-1). This virus is the etiologic agent of ATLL, HAM/TSP and uveitis. It is also related to inflammatory illness like arthritis, infective dermatitis, polymyositis, alveolitis and Sjorgen syndrom. The spontaneous proliferation of T-lymphocytes induced by viral transactivating proteins like Tax and HBZ is one of the most outstanding immunological characteristics of the infection. The role of the proliferation in the pathogenesis is still unknown though some studies have shown that it is higher among HAM/TSP patients. Moreover, it could be responsible for the HTLV-1 remaining proviral load since the virus replicate through division of infected cell. The dynamics of the proliferation ex-vivo is not well known and is usually assessed by incorporating 3[H]-Thymidine to the cultures. This method has several disadvantages one of them being the 3[H]-Thymidine toxicity. This pilot study was aimed at the standardization of a method that assesses the dynamics of the spontaneous T-lymphocytes proliferation using flow cytometry and CarboxyFluorescein diacetate Succinimidyl Ester (CFSE) as a marker. Other objectives were to assess the rates of celular proliferation of both total T lymphocytes and CD4+ and T CD8+ subpopulations; to correlate the celular proliferation with the HTLV-1 viral load and the expression of the viral TAX protein. PBMCs of 30 HTLV-1 infected patients (16 assymptomatic and 14 HAM/TSP) were cultivated for 24, 48, 72, 96 and 120 hours in the presence of CFSE. Cells were obtained by flow cytometry and the results were analysed with the software Flowjo through the percentage of divided cells and the rate of celular division. Cell proliferation was observed in 66.7% of the HTLV-1 infected people. The PBMC spontaneous proliferation was higher in the group of HAM/TSP patients (percentage of divided cells:79%, rate of cellular division79%) compared to the assymptomatic individuals (percentage of divided cells: 50%, rate of cellular division: 56,3%) though this difference was not significant. Spontaneous proliferation can be detected in the first 24 hours of cell cultivation. The intensity of proliferation is similar in T CD4 e T CD8 subpopulations of assympomatic individuals and HAM/TSP patients. There was no correlation between proviral load and percentage of divided cells (r= -0,009; p= 0,9) and the rate of cellular division (r=0,1; p=0,5). The average of the TAX expression in T CD4+ was 2,4±2,4 %. There was a correlation between the expression of TAX protein and the percentage of divided cells (r=0,59; p =0,05) and the rate of cellular division (r=0,60; p=0,05), although not statistically significant. Nevertheless, a positive correlation was found between the percentage of divided T CD4+ cells and the expression of TAX protein (r=0,79; p<0,003), as well as between the rate of cellular division of TCD4+ cells and the expression of TAX protein (r=0,75; p=0,008). As a conclusion, the assessment of spontaneous proliferation by flow cytometry in cultures with CFSE analysed with the FlowJo software allows to identify the cellular proliferation in the first 24 hours of cultivation and to quantify the proportion of T CD4 and TCD8 lymphocytes that proliferated. This method could be usefull to assess drugs that modulate the spontaneous proliferation in PBMCs from HTLV-1 infected individuals.
266

Avaliação do papel dos marcadores CD200, CD43, CD52 e CD123 no diagnóstico diferencial das doenças linfoproliferativas crônicas b

Arlindo, Elissandra Machado January 2015 (has links)
Introdução: as doenças linfoproliferativas de células B maduras correspondem a cerca de 80% das neoplasias linfoides, são caracterizadas pela proliferação clonal de uma célula B precursora em diferentes estágios de diferenciação. A semelhança imunofenotípica a um dado estágio maturativo é relevante para o diagnóstico diferencial através da imunofenotipagem por citometria de fluxo, embora a sobreposição de expressões possa dificultar a identificação correta de cada linfoproliferação. Alguns marcadores são pouco conhecidos nas diferentes linfoproliferações B e há pouca literatura analisando os dados quantitativamente, sendo grande parte qualitativa. Objetivos: este trabalho avalia a expressão quantitativa em intensidade de fluorescência média (IFM) dos anticorpos CD200, CD43, CD52 e CD123 no diagnóstico diferencial das doenças linfoproliferativas B crônicas. Métodos: estudo transversal, com 124 amostras de pacientes em investigação diagnóstica de doenças linfoproliferativas que realizaram imunofenotipagem em um centro de referência em neoplasias hematológicas no período de outubro de 2014 a junho de 2015. Foram analisadas as IFMs de cada marcador nas onze diferentes doenças diagnosticadas. Resultados: as neoplasias dos 124 pacientes analisados foram: 81 leucemias linfocíticas crônicas (LLC), 17 linfomas de zona marginal (LZM), 9 linfomas linfoplasmocíticos (LLPL), 6 linfomas do manto (LM), 2 tricoleucemias (TRL), 2 tricoleucemias variantes (TRLv), 5 linfomas foliculares (LF), 1 linfoma de Burkitt e 1 linfoma difuso de grandes células B (LDGCB). A expressão mediana do CD200 foi de 46,8 (intervalo: 1,5-334). A expressão mediana de CD200 foi maior na TRL (incluindo a TRLv) e na LLC (85 e 61,2, respectivamente). A expressão de IFM do CD200 na TRLv diferiu quando comparado à TRL na sua forma clássica (mediana: 36,1 versus 220,3). A mesma diferença foi observada na expressão do CD123 quando comparada a TRL à TRLv. Verificamos, que casos de LZM demonstraram IFM medianas de CD43 de 7,1 (intervalo: 1,1-106), em comparação a casos de LM e LLC, nos quais as medianas de IFM do CD43 foram 90 e 176, respectivamente. A comparação da intensidade de CD52 entre amostras demostrou diferença estatisticamente significativa entre LLC e LZM com medianas de IFM de 775,5 versus 1297,0 (P=0,04). Conclusões: nossos resultados sugerem que a citometria de fluxo quantitativa desses marcadores pode ser uma ferramenta adicional útil na identificação de alguns tipos de DLPCBs. / Background: lymphoproliferative disorders of mature B cells account for about 80% of the lymphoid malignancies. They are characterized by the clonal proliferation of a B cell precursor at different stages of differentiation. The similarity of a given phenotypical maturation stage is relevant for the differential diagnosis by immunophenotyping, however overlap in cell morphology and immunologic features may difficult the correct identification of each pathology. Some markers are not well known in different B lymphoproliferative neoplasms and there is little literature analyzing the data quantitatively. Objectives: this study evaluated the expression of CD200, CD43, CD52 and CD123 by flow cytometry on B-cell chronic lymphoproliferative disorders (BCLDs) differential diagnosis. Methods: cross-sectional study, of 124 samples from patients for diagnostic investigation of lymphoproliferative disorders who underwent immunophenotyping in a referral center for hematologic malignancies from October 2014 to June 2015. MFIs were analyzed for each marker in eleven different diagnosed pathologies. Results: the diseases of the 124 patients investigated comprised: 81 chronic lymphocytic leukemia (CLL), 17 marginal zone lymphoma (MZL), 9 lymphoplasmacytic lymphoma (LPL), 6 mantle cell lymphoma (MCL), 2 hairy cell leukemia (HCL), 2 hairy cell leukemia variant (HCLv), 5 folicular lymphoma (FL), 1 Burkitt lymphoma (BL) e 1 diffuse large B cell lymphoma (DLBCL). The CD200 median MFI expression was 46,8 (range: 1,5-334). CD200 was higher in HCL (including HCLv) and CLL cells (85 and 61,2 respectively). HCLv difference in CD200 MFI, when compared to classical HCL (median 36,1 versus 220,3). The same difference in CD123 expression was observed when comparing HCL versus HCLv. We found that cases of MZL exhibited CD43 median MFI of 7,1 (range: 1,1-106), in contrast to cases of MCL and CLL, which had median MFIs for CD43 of 90 and 176, respectively. The comparison of CD52 intensity between CLL and MZL samples showed statistically significant difference with a median MFI of 777,5 versus 1297,0 (P=0,04). Conclusion: our results suggest that quantitative flow cytometry of these markers may be a useful additional tool to better identify some types of BCLDs.
267

Quantificação de subpopulações linfocitárias em doadores de repetição de plaquetaférese

Vargas, Luciana do Nascimento January 2016 (has links)
Introdução: A doação de plaquetas por aférese é um método de coleta que vem aumentando em relevância. Sabe-se que esta técnica apresenta inúmeras vantagens em comparação à doação de sangue total. Observamos que há uma preocupação na qualidade dos hemocomponentes enviados ao paciente, no entanto, não se observam muitas pesquisas em busca do cuidado com o doador. Órgãos como o Food and Drug Administration (FDA) já publicaram normas mais restritivas em relação à doação de plaquetas por aférese, pois pesquisas apontaram uma diminuição de algumas células e proteínas do sistema imunológico em doadores de repetição. Objetivos: Analisar doadores de plaquetas de repetição quanto a parâmetros hematimétricos e quantificação de subpopulações linfocitárias comparando-os com um grupo controle composto por doadores de sangue total que não doam há no mínimo um ano ou doando pela primeira vez e, ainda avaliar se a frequência de doações, o tempo de procedimento e o número de plaquetas doadas influenciam na contagem de leucócitos totais e nas subpopulações de linfócitos. Metodologia: Foram analisados 88 indivíduos em um estudo caso-controle, sendo que o grupo controle (CO) incluído foi de doadores de sangue total que haviam doado pela primeira vez ou haviam doado sangue total há mais de um ano. Os casos (CA) incluídos foram os doadores de repetição de plaquetaférese (quatro ou mais doações no último ano). O pareamento foi feito por sexo e idade. As amostras de sangue periférico foram coletadas em tubos contendo EDTA e analisadas em até 6 horas por citometria de fluxo, através da utilização de anticorpos monoclonais anti-CD3, CD4, CD8, HLADR, CD19 e CD56. Resultados: Foram avaliados 44 pares de doadores (caso vs controle). Destes, 81,8% eram homens, a média de idade dos grupos foi de 46 ±13 anos nos casos e 47 ±11 nos controles. Comparando os dois grupos, observou-se diferença estatisticamente significativa (p<0,05) na média de quantificação de leucócitos absolutos CA= 6476,6/μL vs CO=7115,4/μL (p=0,017), na média de linfócitos absolutos CA= 1862,6/μL vs CO= 2239,2/μL (p=0,007) e nos marcadores: CD3+/CD8+ (absoluto) CA= 437/μL vs CO= 597/μL (p=0,01), CD3+/CD4+(%) CA= 47,3/μL vs CO= 42,77/μL (p=0,007). Conclusões: Neste estudo foi possível observar que há uma diminuição em algumas células linfoides dos doadores de repetição em relação aos doadores convencionais, no entanto essa diferença não tem relevância clínica, demonstrando que os intervalos de doações que estes doadores estão sendo submetidos é adequado. A contagem de plaquetas dos doadores de repetição se mantiveram no decorrer do ano, este dado nos auxilia para mantermos um banco de dados de doadores de repetição com uma quantificação de plaquetas adequada, podendo ser convocado sem risco de ser bloqueado por contagem inferior ao preconizado. / Introduction: The donation of platelets by apheresis as a collection method has lately grown in relevance. This technique presents several advantages when compared to total blood donation. We understand there is a concern about the quality of the hemocomponents that are administered to the patients; however, there are not many researches concerned with caring for the donor. Entities such as the Food and Drug Administration (FDA) have published more restricting regulations regarding the donation of platelets by apheresis, since researches indicate a decrease in some cells and proteins present in the immunological systems of repeat donors. Objectives: To analyze repeat donors of platelets with regards to hematimetric parameters and quantification of lymphocyte sub-populations by comparing them with a control group consisting of total blood donors that have not donated blood for the past year at least or that are donating for the first time. Additionally, to evaluate if the frequency of donations, the duration of the procedure, and the donated platelet counts influence in the total leukocyte counts and in the sub-populations of lymphocytes. Methodology: We analyzed 88 individuals in a control case study. The control group (CG) consisted of total blood donors in their first donation or that had donated for the last time more than a year before. The cases (CA) included were the repeat donors by platelet apheresis (four or more donations in the past year). We matched the individuals by gender and age. Peripheral blood samples were collected in tubes containing EDTA and analyzed up until 6 hours later by flow cytometry, through monoclonal antibodies anti-CD3, CD4, CD8, HLADR, CD19, and CD56. Results: 44 pairs of donor were evaluated (case vs control). Among them, 81.8% were men, the average age of the groups was 46 (±13) years in the cases and 47 (±11) in the controls. When comparing the two groups, we observed a statistically significant difference (p<0,05) in the average of the quantification of absolute leukocytes CA= 6476.6/μL vs CG=7115.4/μL (p=0.017), in the average of absolute lymphocytes CA= 1862.6/μL vs CG= 2239.2/μL (p=0.007), and in the markers: CD3+/CD8+ (absolute) CA= 437/μL vs CG= 597/μL (p=0,01), CD3+/CD4+(%) CA= 47.3/μL vs CG= 42.77/μL (p=0.007). Conclusions: We were able to note in this study that there is a significant decrease in some lymphoid cells of repeat donors when compared to conventional donors. This difference, however, is not clinically relevant, which demonstrates that the donation intervals to which the donors are subject are appropriate. Platelet numbers of repeat donors remained the same throughout the year. This piece of data helps us keep a database of repeat donors with an adequate platelet number. These donors can be called for without risking of their being blocked in the screening for a number lower than the recommended.
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Systematika a proměnlivost zdravínku jarního Odontites vernus (Bellardi) Dumort. v České republice / Systematics and variation of Red Bartsia, Odontites vernus (Bellardi) Dumort. in the Czech Republic

BAĎUROVÁ, Tereza January 2012 (has links)
The Master's thesis studied the Odontites vernus group in the Czech Republic. The group was presented by two different taxa based on the seasonal types and the ploidy levels: an early flowering tetraploid Odontites vernus subsp. vernus (2n = 4x = 40) and a late-flowering diploid Odontites vernus subsp. serotinus (2n = 2x = 18). Plants from 33 populations were sampled for measuring the ploidy level and 27 morphological characters for morphological analysis. Two ploidy levels were confirmed in the Czech Republic and a new late flowering tetraploid taxon (2n = 4x = 40) was found. The three taxa were separated from each other based on the seasonal variation, ploidy level, morphology and ecology.
269

The involvement of microglial activation in schizophrenia

van Rees, Geertje Frederique January 2018 (has links)
Abnormal activation of brain microglial cells is widely implicated in the pathogenesis of schizophrenia. The disrupted balance of microglia phenotypes has been hypothesized to influence the clinical course of the disease and affect symptom severity. Previously, the pathophysiology of microglial activation was considered to be intrinsic to the central nervous system. We hypothesised that due to their perivascular localization, microglia can also be activated by factors present in circulating blood. We applied a high-content functional screening platform, to characterize alterations in microglial intracellular signalling cascades induced by schizophrenia patient serum relative to control serum. Using automated sample preparation, fluorescent cellular barcoding and flow cytometry, the applied platform is capable of detecting multiple parallel cell signalling responses in microglia. First, we exposed a human microglia cell line to serum isolated from first-onset drug-naïve schizophrenia patients (n=60) and healthy controls (n=79). We were able to show that peripheral blood serum obtained from schizophrenia patients induced differential microglial cell signalling network responses in vitro. We subsequently assessed whether antipsychotic drug-treatment can normalise the abnormal microglial signalling responses previously identified by exposing microglia cells to serum from antipsychotic treated schizophrenia patients (n=15) and controls (n=17). In addition, in order to assess microglia activation in vivo, we obtained positron emission tomography (PET) imaging data from collaborators, who used a radiotracer to assess potential altered microglia activation in patients suffering from schizophrenia. Finally, as a proof of concept study, we attempted to validate these findings by assessing the effect of serum collected from first-onset drug-naïve schizophrenia patients (n=9), controls (n=12) as well as serum isolated from the same patients subjected to six weeks of clinical treatment with the antipsychotic olanzapine (n=9). This study aimed to identify normalisation of previously detected differences in microglia signalling pathways based on successful in vivo treatment. We demonstrate that peripheral blood serum isolated from schizophrenia patients, independent of their treatment status, is sufficient to trigger microglial cell signalling network responses in vitro, which are indicative of altered STAT3 signalling. We further explored the composition of the serum for differential expression of analytes, previously associated with neuropsychiatric disorders, and the utility of the detected microglial cellular phenotype as a target for novel drug discovery.
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Sinalização celular para apoptose em linhagem celular de adenocarcinoma (MCF-7) e carcinoma ductal invasivo de mama (ZR 7531) tratados com alcalódes isolados de Pterogyne nitens

Duarte, Roberta Aparecida [UNESP] 31 May 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-31Bitstream added on 2014-06-13T18:41:52Z : No. of bitstreams: 1 duarte_ra_dr_arafcf.pdf: 4649782 bytes, checksum: 99bc00374a88b89ba36ff755fc732fa3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O câncer de mama é a maior causa de morbidade e mortalidade entre as mulheres no mundo. Pesquisas revelam vários fatores prognósticos e preditivos para a identificação de pacientes com alto risco de agressividade, metastases e doença recorrente na condição de combater estas estatísticas. Por esta razão, é evidente a necessidade do desenvolvimento de estratégias de tratamento mais eficazes. Estudos prévios com Pterogyne nitens Tul. (Fabaceae-Caesalpinioideae), uma planta nativa do Brasil resultou o isolamento de dois alcalóides guanidínicos. Exibiram atividade seletiva direcionada a DNA deficiente de reparo, sugerindo potencial atividade anticâncer. Objetivo: O objetivo do presente estudo foi avaliar a citotoxicidade e apoptose induzidas pelos alcalóides pteroginina (PGN) and pteroginidina (PGD) em linhagem de adenocarcinoma (MCF-7) e carcinoma ductal invasivo (ZR-7531). Materiais e Métodos: As duas linhagens celulares foram tratadas pelos alcalóides em várias concentrações (0.25 – 10 mM) em dois tempos, t0 (24h) e t24 (24h seguido por 24h pós-tratamento). O ensaio de citotoxicidade foi determinado pelo teste de MTT; a morte celular (apoptose e necrose) foi analisada usando os métodos Hoechst 33342/iodeto propídio, Kit de Anexina V-FITC e atividade de Caspases 3/7. Resultados: Os tratamentos com os alcalóides demonstraram citotoxicidade concentração-resposta nas linhagens de câncer de mama. Para avaliação da apoptose foi observado um intense efeito concentraçãoresposta em apoptose tardia/necrose e discreto sinal para apoptose precoce em todas concentrações (p<0,01). No ensaio Hoechst/iodeto, observou diferença significante entre os estágios de apoptose precoce e tardia de ambas linhagens. A pteroginina no período t0 e t24, e pteroginidina no período t0 demonstraram possuir intenso efeito concentração... / Breast cancer is a major cause of morbidity and mortality among women worldwide. Research has elucidated several specific prognostic and predictive factors to identify patients at high risk of the aggressive disease, metastasis and recurrence of the disease in order to combat these statistics. For this reason, there is an obvious need to develop more efficacious treatment strategies. Previous studies on Pterogyne nitens Tul. (Fabaceae-Caesalpinioideae), a native plant of Brazil, resulted in the isolation of two guanidine alkaloids, exhibited selective activity towards a DNA repair-deficient, suggesting potential anti-cancer activity. Objective: The aim of the present study was to evaluate the citotoxicity and apoptosis induced by alkaloids pterogynine (PGN) and pterogynidine (PGD) in human adenocarcinoma cell line (MCF-7) and human invasive ductal carcinoma cell line(ZR-7531). Material and Methods: The two cell lines were treated by both alkaloids at several concentrations (0.25 – 10 mM) and two time points, 24h (t0) and 24h followed by 24h pos-treatment (t24). The cytotoxicity assay was determined by MTT assay; the cell death (apoptosis and necrosis) were analyzed using the dye Hoechst 33342/propidium iodide, Annexin V-FITC and Caspase 3/7 activity. Results: The treatments with the alkaloids demonstrated citotoxicity effect concentrationresponse in breast cell lines. Apoptosis evaluation, pterogynine and pterogynidine has an intense effect concentration-response of late apoptosis/necrosis and a discrete signal of early apoptosis in all of the concentrations (p<0.01). Hoechst/iodide assay, it was observe significant difference among the stages of early and late apoptosis in the both cells lines. Pterogynine for the period of t0 and t24, and pterogynidine for the period of t0 demonstrated to possess an intense concentrationresponse... (Complete abstract click electronic access below)

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