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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.
1

Evaluation of a standardized platelet concentration in samples from platelet concentrates measured over time with impedance aggregometry

Sofie, Sjöberg January 2015 (has links)
Platelet transfusions can be necessary during treatment of patients with thrombocytopenia or impaired platelet function. Platelet function in platelet concentrates (PC) deteriorate with storage time. Studying swirling is often used to control the quality of PC’s before transfusion but the method has some disadvantages. Therefore other methods can be useful, for example impedance aggregometry (IA, Multiplate® Analyzer) to measure platelet function.      In this study the change in platelet function over time was examined in buffy coat and apheresis platelets with IA where aggregation had been induced with adenosine diphosphate (ADP) and collagen. PC’s were tested on day 1, 4 and 7 after donation. One of the main aims of this study was to evaluate if dilution to a standardized platelet concentration (800x109 platelets/L) for IA of PC’s could be used, since platelet concentration has been shown to influence aggregation. The effect of pathogen inactivation (INTERCEPT) on platelet function and the importance of fibrinogen for aggregation were also studied.      The dilution of platelet samples reduced the range of measured values and was suitable to use with collagen but not ADP. The platelet function decreased significantly over time with both agonists. There was a significant difference between pathogen inactivated and gamma irradiated PC’s with collagen activation on day 1. Fibrinogen was shown to be of importance for platelet aggregation, but other factors in plasma seem to be necessary too.      In conclusion, IA is a suitable method for following change in aggregability over time in PC’s and sample dilution reduced variation in results.
2

Caracterização molecular de espécies da família Anaplasmataceae em leucócitos e plaquetas de cães de Jaboticabal-SP e de Campo Grande-MS /

D'agnone, Ana Silvia. January 2006 (has links)
Orientador: Rosangela Zacarias Machado / Banca: Matias Pablo Juan Szabó. / Banca: Mirela Tinucci Costa. / Banca: Odilon Vidotto / Banca: Rodrigo Martins Soares / Resumo: Este estudo foi realizado objetivando-se detectar e identificar a presença de material genômico de agentes pertencentes à Família Anaplasmataceae em 55 cães com inclusões citoplasmáticas encontrados em células leucocitárias granulocíticas, monocíticas e plaquetas, compatíveis com infecção por Ehrlichia canis, E. chaffeensis, E. ewingii, A. phagocytophilum, A. platys ou Neorickettsia risticii. A ocorrência natural de Babesia canis também foi avaliada pois vetor Rhipicephalus sanguineus, é o principal carrapato encontrado em cães no Brasil. Também objetivou-se realizar, através da utilização de técnicas de Seqüenciamento de um fragmento do gene 16S rRNA, a caracterização parcial dos fragmentos das amostras positivas encontradas neste estudo, e comparar as seqüências dos fragmentos obtidos com as seqüências apresentadas previamente no GenBank, iniciando a realização de estudos filogenéticos das seqüências encontradas. Amostras de sangue foram colhidas de 25 e 30 cães atendidos nos Hospitais Veterinários da Universidade Estadual Paulista-Unesp, Câmpus de Jaboticabal-SP e Universidade para o Desenvolvimento do Estado e da região do Pantanal-UNIDERP, Campo Grande- MS, respectivamente. Dentre as inclusões citoplasmáticas encontradas neste estudo foi observado uma grande diversidade na morfologia, tamanho, coloração e localização das inclusões. DNA de agentes Família Anaplasmataceae foram detectados em 45/55 das amostras sangüíneas examinadas (81,8%), sendo destas 32 (58,18%) e 13 (23,63%) positivas para Ehrlichia canis e Anaplasma platys, respectivamente. Dez animais que foram incluídos neste estudo por apresentarem inclusões citoplasmáticas foram negativos quando uma segunda confecção de esfregaço de papa leucocitária corada pelo Giemsa foi realizada, e também... (Resumo completo, clicar aesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the natural occurrence of Anaplasmataceae agents (Ehrlichia canis, E. chaffeensis, E. ewingii, A. phagocytophilum, A. platys and Neorickettsia risticii) using molecular techniques. For this purpose a group of fifty-five supposedly infected dogs from two different Brazilian states (São Paulo and Mato Grosso do Sul) that showed suggestive Anaplasmataceae agent intracitoplasmic inclusions in white blood cells and platelets were analysed. The natural occurrence of Babesia canis was also evaluated, because its vector is also Brazilian dog tick, Rhipicephalus sanguineus. Sequencing of a partial phragment of 16S rRNA gene from the positive samples were performed to conduct phylogenetic study. The evaluated blood cells of the studied dog population displayed a wide variety in shapes, sizes, stain pattern and localization of the inclusions. Anaplasmataceae DNA were amplified in 45/55 (81.8%) examined blood samples. Thirty-two samples were positive for E. canis (58.18%) and thirteen for Anaplasma platys (23.63%). Ten animals were negative by PCR and an analyses of a second Buffy coat smear. The obtained nucleotide sequences were analysed for similarity of the 16S rRNA gene sequence using Blast with other sequences available in the GenBank database. The sequences obtained from E. canis positive were closely related to E. canis from Spain (Acession number AY 394465) presenting an identity percentage of between 94.82% and 99.67%. Sequences from Anaplasma sp and Anaplasma platys positive samples were closely related to A. platys from Venezuela (Genbank Acession number AF 399917) presenting an identity betwwen 96.52% and 99.69%, and A. platys from Spain (Genbank Acession number AY 530 806\0 presenting... (Complete abstract, click electronic access below) / Doutor
3

Caracterização molecular de espécies da família Anaplasmataceae em leucócitos e plaquetas de cães de Jaboticabal-SP e de Campo Grande-MS

D'agnone, Ana Silvia [UNESP] 21 September 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-09-21Bitstream added on 2014-06-13T20:44:55Z : No. of bitstreams: 1 dagnone_as_dr_jabo.pdf: 2655933 bytes, checksum: 8f6122da8b67a36f40a31689501140e2 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este estudo foi realizado objetivando-se detectar e identificar a presença de material genômico de agentes pertencentes à Família Anaplasmataceae em 55 cães com inclusões citoplasmáticas encontrados em células leucocitárias granulocíticas, monocíticas e plaquetas, compatíveis com infecção por Ehrlichia canis, E. chaffeensis, E. ewingii, A. phagocytophilum, A. platys ou Neorickettsia risticii. A ocorrência natural de Babesia canis também foi avaliada pois vetor Rhipicephalus sanguineus, é o principal carrapato encontrado em cães no Brasil. Também objetivou-se realizar, através da utilização de técnicas de Seqüenciamento de um fragmento do gene 16S rRNA, a caracterização parcial dos fragmentos das amostras positivas encontradas neste estudo, e comparar as seqüências dos fragmentos obtidos com as seqüências apresentadas previamente no GenBank, iniciando a realização de estudos filogenéticos das seqüências encontradas. Amostras de sangue foram colhidas de 25 e 30 cães atendidos nos Hospitais Veterinários da Universidade Estadual Paulista-Unesp, Câmpus de Jaboticabal-SP e Universidade para o Desenvolvimento do Estado e da região do Pantanal-UNIDERP, Campo Grande- MS, respectivamente. Dentre as inclusões citoplasmáticas encontradas neste estudo foi observado uma grande diversidade na morfologia, tamanho, coloração e localização das inclusões. DNA de agentes Família Anaplasmataceae foram detectados em 45/55 das amostras sangüíneas examinadas (81,8%), sendo destas 32 (58,18%) e 13 (23,63%) positivas para Ehrlichia canis e Anaplasma platys, respectivamente. Dez animais que foram incluídos neste estudo por apresentarem inclusões citoplasmáticas foram negativos quando uma segunda confecção de esfregaço de papa leucocitária corada pelo Giemsa foi realizada, e também... / The aim of this study was to evaluate the natural occurrence of Anaplasmataceae agents (Ehrlichia canis, E. chaffeensis, E. ewingii, A. phagocytophilum, A. platys and Neorickettsia risticii) using molecular techniques. For this purpose a group of fifty-five supposedly infected dogs from two different Brazilian states (São Paulo and Mato Grosso do Sul) that showed suggestive Anaplasmataceae agent intracitoplasmic inclusions in white blood cells and platelets were analysed. The natural occurrence of Babesia canis was also evaluated, because its vector is also Brazilian dog tick, Rhipicephalus sanguineus. Sequencing of a partial phragment of 16S rRNA gene from the positive samples were performed to conduct phylogenetic study. The evaluated blood cells of the studied dog population displayed a wide variety in shapes, sizes, stain pattern and localization of the inclusions. Anaplasmataceae DNA were amplified in 45/55 (81.8%) examined blood samples. Thirty-two samples were positive for E. canis (58.18%) and thirteen for Anaplasma platys (23.63%). Ten animals were negative by PCR and an analyses of a second Buffy coat smear. The obtained nucleotide sequences were analysed for similarity of the 16S rRNA gene sequence using Blast with other sequences available in the GenBank database. The sequences obtained from E. canis positive were closely related to E. canis from Spain (Acession number AY 394465) presenting an identity percentage of between 94.82% and 99.67%. Sequences from Anaplasma sp and Anaplasma platys positive samples were closely related to A. platys from Venezuela (Genbank Acession number AF 399917) presenting an identity betwwen 96.52% and 99.69%, and A. platys from Spain (Genbank Acession number AY 530 806\0 presenting... (Complete abstract, click electronic access below)
4

A review of the economic consequences of a policy of universal leucodepletion as compared to existing practices

Clare, Virginia Mary January 2009 (has links)
Leucodepletion, the removal of leucocytes from blood products improves the safety of blood transfusion by reducing adverse events associated with the incidental non-therapeutic transfusion of leucocytes. Leucodepletion has been shown to have clinical benefit for immuno-suppressed patients who require transfusion. The selective leucodepletion of blood products by bed side filtration for these patients has been widely practiced. This study investigated the economic consequences in Queensland of moving from a policy of selective leucodepletion to one of universal leucodepletion, that is providing all transfused patients with blood products leucodepleted during the manufacturing process. Using an analytic decision model a cost-effectiveness analysis was conducted. An ICER of $16.3M per life year gained was derived. Sensitivity analysis found this result to be robust to uncertainty in the parameters used in the model. This result argues against moving to a policy of universal leucodepletion. However during the course of the study the policy decision for universal leucodepletion was made and implemented in Queensland in October 2008. This study has concluded that cost-effectiveness is not an influential factor in policy decisions regarding quality and safety initiatives in the Australian blood sector.
5

Jämförelse mellan två nedkylningsmetoder av helblodsenheter för vidare framställning av trombocytkoncentrat avsedda för transfusion / Comparison between two cooling methods of whole blood units for further preparation of platelet concentrates intended for transfusion

Bäckström, Annie January 2018 (has links)
Trombocytopeni behandlas primärt med trombocyttransfusion. Trombocytkoncentraten kan erhållas genom poolning av lättcellskikt framställda ur helblodsenheter från flera blodgivare. Helblodsenheterna kyls vanligen ner på en CompoCool®-platta för att snabbt komma ner till rumstemperatur och kan då prepareras redan efter 2 h. Detta brukar vara logistiskt fördelaktigt och gynnar erytrocyterna som framställs ur samma helblodsenheter. Det går även att låta helblodsenheterna kylas ner i rumstemperatur vilket å andra sidan sägs ge ett högre trombocytutbyte då studier visat att trombocyter är känsliga för kyla. Syftet med examensarbetet var att framställa och jämföra kvaliteten på trombocytkoncentrat där helblodsenheten hade kylts ner på CompoCool®-platta respektive kylts ner i rumstemperatur. Hypotesen var att trombocytutbytet skulle bli högre vid nedkylning av helblodsenheten i rumstemperatur än vid nedkylning på CompoCool®-platta. Framställningen av trombocytkoncentraten gjordes genom poolning av 5 st lättcellskikt och en påse trombocytsuspensionsmedium efterföljt av centrifugering och separation i en automatisk blodkomponents separator. Kvalitén utvärderades med avseende på trombocytkoncentration, leukocytkoncentration, swirling samt bakterieodling. Samtliga resultat för kvalitetskontrollerna låg inom de rekommenderade gränsvärdena. Det beräknade t-testet för trombocytkoncentrationen var högre än det kritiska t-värdet vilket innebar att det var en signifikant skillnad mellan de olika nedkylningsmetoderna. Genom användning av de erhållna resultaten kunde hypotesen bekräftas och slutsatsen dras att trombocytutbytet är signifikant högre då helblodsenheten kyls ner i rumstemperatur jämfört med CompoCool®-platta.
6

Evaluation of Storage Conditions for Assessing DNA Damage Using the Comet Assay

Villavicencio, Dante 02 November 2006 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The single cell gel electrophoresis assay (comet assay) is a useful tool for monitoring individuals who may be at risk of DNA damage and the ensuing process of carcinogenesis or other disease states. Leukocytes in blood samples provide a means of obtaining cells for use in the comet assay. However instances may arise when samples must be stored for later analysis. The present study investigated the effects of storage conditions on DNA damage in the form of strand breaks and oxidized bases in rat and human leukocytes using the comet assay. Whole blood and buffy coat samples were stored at room temperature or 4ºC for 1, 2, 24, and 48 hours or cryopreserved at -80ºC for 1 day and 1, 2, 3, and 4 weeks. The results show that the time of storage is limited if the whole blood or buffy coat samples are stored at room temperature or 4ºC. However, if cryopreserved using glycerol or DMSO as the cryoprotectant, the samples may be stored for at least 4 weeks without DNA strand breaks or oxidative damage deviating significantly from the fresh samples.

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