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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

Development of a new extraction method for platelet-rich plasma and partial purification of platelet-derived growth factor and transforming growth factor beta

Laurens, Ilze January 2013 (has links)
Platelet-rich plasma (PRP) is the cell free plasma, which has an enriched concentration of platelets and clotting factors with the ability to enhance the natural healing process. PRP is often used by physicians in an office setting to accelerate the healing of a variety of sports related injuries, chronic wounds and enhance skin rejuvenation. PRP mimics the wound healing cascade by enhancing the recruitment, proliferation and differentiation of cells involved in tissue regeneration. Although PRP is used to enhance healing, the efficacy thereof is debated as no clear-cut set of parameters is available that device manufacturers and protocols should follow. The lack of uniformity in the PRP preparation methods results in differing PRP volume, platelet contents and unavoidably platelet-derived growth factors. Therefore, the aim of this study was to develop a simple and rapid method for preparing autologous PRP in an office setting using a tabletop centrifuge for point-of-care use. The simplified preparation procedure involved a single centrifugation step of 18 ml of whole blood, which sufficiently enriched the platelet content in the PRP fraction. As activated platelets express and release growth factors and cytokines that mediate the different phases of the wound healing cascade, the extracted PRP fraction was activated with an ethanol, calcium chloride (CaCl2) and platelet poor plasma (PPP) preparation in glass containers, without the collection of additional blood as required in some protocols. The activated PRP formed a fibrin clot, trapping the degranulating platelets and its released growth factors. The concentration of TGF- 1 obtained from the fibrin clot was 45.49 ± 3.80 ng/ml, in range with the available literature. During the in vitro studies, the extracted PRP by the developed method was able to significantly induce cell proliferation in a dose dependent manner. Cells enumerated with the crystal violet assay indicated that the cells treaded with 5% or 10% PRP significantly increased the percentage of viable cells to 165-176% and 156-158%, when compared to the positive controls. Cells enumerated with the MTT-assay indicated that the cells treaded with 5% or 10% PRP increased the percentage of viable cells to 79-91% and 87-105% which is comparable to that of the positive control. Data from the cellular proliferation assays indicate that sufficient plateletderived growth factors had been obtained with the preparation procedure. Furthermore, data from the in vivo studies indicated that the extracted PRP was able to augment soft tissue regeneration and bone formation. Treatment with the activated PRP resulted in symptom reduction and accelerated healing of various injuries. The simplified preparation and the use of the provided study product packaged in a kit developed during this study will enable physicians to easily obtain autologous PRP, in an office setting for point-of-care use, with the ability to induce tissue regeneration. / Dissertation (MSc)--University of Pretoria, 2013 / gm2014 / Pharmacology / unrestricted
2

Applying Mesenchymal Stromal Cells and Platelet-Rich Plasma on a Collagen Matrix to Improve Fascial Repair

Perko, John C. 12 July 2012 (has links)
No description available.
3

Anticancer roles of platelets and aspirin tested on A549 cells

Shang, Lijun, Zhang, Z., Chen, F. 08 1900 (has links)
no / Aspirin, formally known as acetylsalicylic (ASA), is most widely used and cheapest over-the counter drugs. It is used not only for the common fevers, headaches and inflammation, but also for reducing the risk of heart attacks. In recent years, it is also linked to anti-cancer potential. Recently the US Preventive Services Working Group (UPSTF) release aspirin as a guide for cardiovascular disease and primary prevention of colorectal cancer. Platelets have been shown to play a crucial role in cancer metastasis for many years and are proposed to have an intimate reciprocal crosstalk with cancer cells. They may alter the properties of each other and have reciprocal effects. But the exact role of platelets in modifying the tumor cell properties has not been established. In clinical, cancer patients may receive platelets from outside to treat thrombocytopenia and bleeding induced by intensive chemotherapy. Therefore understanding the exact role of platelets in carcinogenesis always is a research interest, especially when evaluating anti-cancer drugs. In this study we exam the effect of platelets on viability, proliferation and adhesion of lung cancer cells A549 in culture conditions, using different concentrations of platelet rich plasma (PRP) with and without the presence of antiplatelet drug aspirin. The tumor cell EMT transformation was also investigated under different combination of PRP and aspirin in vitro. Our data showed that low-dose of aspirin can promote cell proliferation and high-dose of aspirin could inhibit cell proliferation. High concentrations of platelet-rich plasma can inhibit cell proliferation but low concentrations of platelet-rich plasma had no significant effect on cell proliferation. Platelet-rich plasma can gather around the cell to form a gelatinous film, and this lead us to a promoted tumor cell distant metastasis model. We further found out that the combination of aspirin and PRP could increase cell viability compared to single use of PRP and Aspirin can affect cell proliferation by inhibiting platelet effects. Platelet-rich plasma reduces the adhesion of A549 cell can be attenuated by aspirin. Further works will focus on combination of different doses of aspirin and PRP to confirm the above results. Other format of aspirin (nano-form) and other NSAID inflammatory drugs like Ibuprofen will also be tested. / Abstract of conference paper.
4

Efeito do plasma rico em plaquetas associado ao uso do LASER terapêutico em desmite proximal do ligamento suspensor do boleto / Effect of PRP associated to laser therapy in proximal supensory desmites

Ramos, Paula Andrea Ramirez 11 July 2013 (has links)
A cicatrização das lesões ligamentares é lenta e muitas vezes ineficiente. Uma vez lesado, o ligamento suspensor do boleto (LSB) dificilmente recupera suas propriedades biomecânicas originais. A desmite do LSB proximal dos membros torácicos ocorre em cavalos de todas as raças e todas as disciplinas esportivas. O objetivo deste trabalho foi avaliar clinicamente e por ultrassonografia, a influência do plasma rico em plaquetas (PRP), e do PRP associado ao LASER terapêutico, na cicatrização da região proximal do LSB, em cavalos com desmite induzida por colagenase. Para isto foram utilizados 18 animais sem raça definida, distribuídos em três grupos. O G1 foi formado por seis animais, submetidos a indução da desmite na região proximal do LSB, que não receberam qualquer tratamento. O G2 foi formado por seis animais, que foram submetidos a desmite induzida e após três semanas receberam aplicação intralesional de PRP guiada pelo ultrassom. O G3 foi formado por seis animais, que após indução da desmite receberam tratamento com LASER terapêutico a partir da segunda semana, e na terceira semana pós-lesão receberam aplicação intralesional de PRP guiada pelo ultrassom. A indução da desmite foi realizada por meio de infiltração guiada pelo ultrassom na região proximal do LSB, sendo este considerado o tempo 0. A cada semana e até a semana oito, os cavalos foram avaliados clinicamente, por ultrassonografia e por análise cinemática, ao trote em linha reta. Houve diferença significativa na comparação entre grupos para as variáveis aumento de volume na avaliação clínica, e área no corte transversal do ligamento e, área no corte transversal da lesão na avaliação ultrassonográfica. Na comparação entre os diferentes momentos de observação as variáveis aumento de volume e dor à palpação do G2 e G3 mostraram escores maiores quando comparados ao G1, sendo que o G2 apresentou escore maior que o G3. Ultrassonograficamente, a ecogenicidade da lesão mostrou diminuição dos escores, a partir da quinta semana de avaliação nos grupos tratados. As demais variáveis clínicas ou ultrassonográficas, bem como a análise cinemática da claudicação não mostraram diferenças significativas entre os grupos. O PRP, apesar de ocasionar inflamação leve e transitório após infiltração, influenciou positivamente o processo de cicatrização da parte proximal do LSB, com um efeito analgésico adicional quando associado ao LASER terapêutico. / The healing process of injured ligaments is slow and often inefficient. Once damaged the suspensory ligament (SL) hardly recover their original biomechanical properties. The forelimb proximal suspensory ligament desmitis occurs in horses of all breeds and all sports. The aim of this study was to evaluate clinically and ultrasonographically, the influence of platelet-rich plasma (PRP), and PRP associated with LASER therapy, on the healing process of the proximal region of the SL in horses with collagenase-induced demitis. For this purpose it were used 18 cross breed horses divided into 3 groups. G1 was composed of six horses subjected to induction of proximal suspensory desmitis, with no treatment. G2 was composed of six horses subjected to desmitis induction and after three weeks they received ultrasound-guided intralesional injection of PRP. G3 was composed of six horses subjected to desmitis induction and after two weeks they received laser therapy and one week later they received intralesional guided-ultrasound injection of PRP. Induction of desmitis was made using ultrasound-guided infiltration in PSL, which was considered day zero. Horses were evaluated clinically, in straight line trot for cinematic analysis and ultrasonographically, every week until eighth week. There were significant difference between groups for swelling, the cross-sectional area of the ligament, and the cross-sectional area of the injury on ultrasound evaluation. Comparing the different times of observation, descriptively were a difference for G2 and G3 in the clinical variables that evaluated swelling and pain on palpation, showed higher scores compared to the G1, and G2 had higher scores than the G3. Sonographically, the echogenicity of the lesion showed decreased scores from the fifth week of evaluation in the treated groups. The other clinical variables or ultrasound, as well as the kinematic analysis of lameness showed no significant differences between groups. PRP, although causing transient and mild inflammation after infiltration, positively influenced the healing process of the proximal part of the SL, with additional analgesic effect when combined with laser therapy.
5

Efeito do plasma rico em plaquetas associado ao uso do LASER terapêutico em desmite proximal do ligamento suspensor do boleto / Effect of PRP associated to laser therapy in proximal supensory desmites

Paula Andrea Ramirez Ramos 11 July 2013 (has links)
A cicatrização das lesões ligamentares é lenta e muitas vezes ineficiente. Uma vez lesado, o ligamento suspensor do boleto (LSB) dificilmente recupera suas propriedades biomecânicas originais. A desmite do LSB proximal dos membros torácicos ocorre em cavalos de todas as raças e todas as disciplinas esportivas. O objetivo deste trabalho foi avaliar clinicamente e por ultrassonografia, a influência do plasma rico em plaquetas (PRP), e do PRP associado ao LASER terapêutico, na cicatrização da região proximal do LSB, em cavalos com desmite induzida por colagenase. Para isto foram utilizados 18 animais sem raça definida, distribuídos em três grupos. O G1 foi formado por seis animais, submetidos a indução da desmite na região proximal do LSB, que não receberam qualquer tratamento. O G2 foi formado por seis animais, que foram submetidos a desmite induzida e após três semanas receberam aplicação intralesional de PRP guiada pelo ultrassom. O G3 foi formado por seis animais, que após indução da desmite receberam tratamento com LASER terapêutico a partir da segunda semana, e na terceira semana pós-lesão receberam aplicação intralesional de PRP guiada pelo ultrassom. A indução da desmite foi realizada por meio de infiltração guiada pelo ultrassom na região proximal do LSB, sendo este considerado o tempo 0. A cada semana e até a semana oito, os cavalos foram avaliados clinicamente, por ultrassonografia e por análise cinemática, ao trote em linha reta. Houve diferença significativa na comparação entre grupos para as variáveis aumento de volume na avaliação clínica, e área no corte transversal do ligamento e, área no corte transversal da lesão na avaliação ultrassonográfica. Na comparação entre os diferentes momentos de observação as variáveis aumento de volume e dor à palpação do G2 e G3 mostraram escores maiores quando comparados ao G1, sendo que o G2 apresentou escore maior que o G3. Ultrassonograficamente, a ecogenicidade da lesão mostrou diminuição dos escores, a partir da quinta semana de avaliação nos grupos tratados. As demais variáveis clínicas ou ultrassonográficas, bem como a análise cinemática da claudicação não mostraram diferenças significativas entre os grupos. O PRP, apesar de ocasionar inflamação leve e transitório após infiltração, influenciou positivamente o processo de cicatrização da parte proximal do LSB, com um efeito analgésico adicional quando associado ao LASER terapêutico. / The healing process of injured ligaments is slow and often inefficient. Once damaged the suspensory ligament (SL) hardly recover their original biomechanical properties. The forelimb proximal suspensory ligament desmitis occurs in horses of all breeds and all sports. The aim of this study was to evaluate clinically and ultrasonographically, the influence of platelet-rich plasma (PRP), and PRP associated with LASER therapy, on the healing process of the proximal region of the SL in horses with collagenase-induced demitis. For this purpose it were used 18 cross breed horses divided into 3 groups. G1 was composed of six horses subjected to induction of proximal suspensory desmitis, with no treatment. G2 was composed of six horses subjected to desmitis induction and after three weeks they received ultrasound-guided intralesional injection of PRP. G3 was composed of six horses subjected to desmitis induction and after two weeks they received laser therapy and one week later they received intralesional guided-ultrasound injection of PRP. Induction of desmitis was made using ultrasound-guided infiltration in PSL, which was considered day zero. Horses were evaluated clinically, in straight line trot for cinematic analysis and ultrasonographically, every week until eighth week. There were significant difference between groups for swelling, the cross-sectional area of the ligament, and the cross-sectional area of the injury on ultrasound evaluation. Comparing the different times of observation, descriptively were a difference for G2 and G3 in the clinical variables that evaluated swelling and pain on palpation, showed higher scores compared to the G1, and G2 had higher scores than the G3. Sonographically, the echogenicity of the lesion showed decreased scores from the fifth week of evaluation in the treated groups. The other clinical variables or ultrasound, as well as the kinematic analysis of lameness showed no significant differences between groups. PRP, although causing transient and mild inflammation after infiltration, positively influenced the healing process of the proximal part of the SL, with additional analgesic effect when combined with laser therapy.
6

Gel de Plasma Rico em Plaquetas (PRP) e associação de gel de PRP com células-tronco mesenquimais de tecido adiposo humano: análise físico-química, morfológica e de viabilidade celular / Platelet-rich plasma gel (PRP) and PRP-gel association with human adipose-derived mesenchymal stem cells: physico-chemical, morphological and cell viability analysis

Santos, Natália Cristine Dias dos [UNESP] 09 November 2017 (has links)
Submitted by Natalia Cristine Dias Dos Santos null (santos.nataliacris@gmail.com) on 2018-01-04T14:17:17Z No. of bitstreams: 1 Dissertação.pdf: 3720898 bytes, checksum: 25acdc7e7879412ae2dcd73e6d9407ea (MD5) / Approved for entry into archive by Laura Akie Saito Inafuko (linafuko@assis.unesp.br) on 2018-01-08T15:30:42Z (GMT) No. of bitstreams: 1 santos_ncd_me_assis.pdf: 3720898 bytes, checksum: 25acdc7e7879412ae2dcd73e6d9407ea (MD5) / Made available in DSpace on 2018-01-08T15:30:42Z (GMT). No. of bitstreams: 1 santos_ncd_me_assis.pdf: 3720898 bytes, checksum: 25acdc7e7879412ae2dcd73e6d9407ea (MD5) Previous issue date: 2017-11-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Vários estudos têm apontado que a interação de plasma rico em plaquetas (PRP) com células-tronco mesenquimais de tecido adiposo humano (CT-TAs) é capaz de otimizar o processo regenerativo, estimulando a angiogênese e o recrutamento de células para o local da lesão. O avanço no conhecimento sobre os aspectos físico-químicos do gel de PRP, bem como na interação e no comportamento das CT-TAs quando associadas ao gel poderão resultar em aplicações práticas em processos de regeneração tecidual. Em função disso, objetivou-se analisar diferentes parâmetros relativos a aspectos morfológicos, físico-químicos e estrutural do gel de PRP isolado ou em associação com CT-TAs (PRP/CT-TAs). As análises dos géis foram realizadas por meio da microscopia eletrônica de varredura (MEV) e da técnica de espectroscopia no infravermelho com transformada de Fourier (FTIR). Também foi avaliada a viabilidade e migração das CT-TAS após associação ao gel de PRP. Os resultados mostraram que as CT-TAs continuam viáveis, mantendo suas propriedades, assim como o gel de PRP, após a associação. Não foram observadas alterações estruturais nos géis de PRP isolado e PRP/CT-TAs, preservando os perfis físico-químicos das amostras. Concomitantemente com estes resultados, observou-se que o gel de PRP pode proporcionar um ambiente favorável às células, permitindo proliferação e migração celular. Os resultados obtidos permitem concluir que o gel de PRP pode ser usado como um potencial scaffold, mantendo as células viáveis quando encapsuladas, preservando os aspectos físico-químicos das CT-TAs e do PRP quando em associação. Além disso, pode-se propor que gel de PRP exerce efeitos positivos sob as CT-TAs, estimulando a proliferação e a viabilidade celular. / Several studies have shown that the platelet-rich plasma (PRP) in association with human adipose-derived mesenchymal stem cells (h-AdMSCs) is able to optimize the regenerative process, stimulating angiogenesis and the recruitment of cells to the lesion site. Advancing in the knowledge of the physico-chemical aspects of PRP-gels, as well as in the interaction and behavior of h-AdMSCs when associated to the gel will result in practical applications in tissue regeneration processes. Therefore, the aim of this study was to evaluate different morphological, physic-chemical and structural parameters of the isolated PRP-gel or in association with h-AdMSCs (PRP/h-AdMSCs). The PRP-gels were submitted to scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy technique (FTIR). The h-AdMSCs viability and migration after association with the PRP-gel were also evaluated. The results showed that as h-AdMSCs remain viable, retaining their properties, as the PRP gel, after association. There were no structural changes in the PRP gels isolated and PRP/h-AdMSCs, so maintaining the physical-chemical profiles of the samples. Additionally to these results, it was observed that the PRP-gel can provide a favorable environment for cells, allowing its proliferation and migration. In summary, it is possible to conclude that PRP-gel can be used as a potential scaffold, maintaining cell viability when encapsulated and preserving the physical-chemical aspects of h-AdMSCs and PRP when in association. In addition, it may be proposed that PRP gel exert chemotatic effects for h-AdMSCs, stimulating cell proliferation and viability.
7

Intraläsionale Anwendung von autologem thrombozytenangereicherten Plasma und xenogener, azellulärer, porziner Matrix bei Fesselträgerläsionen beim Pferd - eine klinische, vergleichende Studie

Lutz, Sebastian Raphael 31 May 2011 (has links)
In der vorliegenden Studie wurde an 109 Patienten mit einer Erkrankung des Fesselträgers retrospektiv untersucht, ob die intraläsionale Applikation von autologem thrombozyten-reichem Plasma (PRP) Vorteile gegenüber der intraläsionalen Applikation von xenogener azellulärer Matrix aus porziner Harnblasenmukosa (ACell Vet™ UBM Powder) besitzt. Die gesamten Daten zum Patientenmaterial entstammen einer großen, schwerpunktmäßig orthopädisch orientierten Pferdeklinik. In die Gruppe mit Thrombozyten angereichertem Plasma (PRP) wurden 75 Patienten aufgenommen. Es wurden 3 verschieden Methoden zur Herstellung von thrombozytenreichem Plasma verwendet. Als Vergleichsgruppe dienten 34 Patienten, welche mit einer xenogenen Therapieform (ACell™) am Fesselträger behandelt wurden. Initial wurden alle Patienten klinisch und ultrasonographisch untersucht, wobei bei allen Patienten ein frischer oder alter aufgefrischter/chronischer Schaden am Fesselträger dargestellt werden konnte. Die Wahl der Therapieform richtete sich nach der Einschätzung, der Präferenz und den Erfahrungen des jeweiligen behandelnden Tierarztes unter Berücksichtigung des finanziellen Aufwandes für die Patientenbesitzer. Alle Patienten wurden entweder mit PRP oder mit ACell™ behandelt und Boxenruhe in Verbindung mit einem steigernd aufgebauten Schritt- und Aufbautrainingsprogramm verordnet. Die Nachuntersuchungen zur Kontrolle des Heilungserfolges und -fortschrittes beinhalteten eine klinische Lahmheitsuntersuchung sowie eine ultrasonographische Untersuchung. Je nach klinischer und ultrasonographischer Entwicklung wurde das Bewegungsprogramm angepasst. Zum Abschluss der Studie konnte als Resultat festgestellt werden, dass 45 (60 %) Patienten der PRP Gruppe ihr ursprüngliches Leistungsniveau wieder erreicht hatten, 8 (10,7 %) Patienten konnten ihr ursprüngliches Leistungsniveau nicht wieder erreichen, 17 (22,7 %) Patienten erlitten ein Rezidiv und ein (1,3 %) Patient musste euthanasiert werden. Im Vergleich dazu erreichten 20 (58,8 %) Patienten der ACell™ Gruppe wieder ihr ur-sprüngliches Leistungsniveau, 5 (14,7 %) Patienten konnten ihr ursprüngliches Leistungs-niveau nicht wieder erreichen, 7 (20,6 %) erlitten ein Rezidiv und ein (2,9 %) Patient musste euthanasiert werden. Die Unterschiede im Resultat sind statistisch nicht signifikant. Ein statistisch signifikanter Unterschied (p= 0,05) ist allerdings bei der Dauer der Rehabilitationsphase zu beobachten. Im Durchschnitt benötigten erfolgreich therapierte PRP Patienten signifikant weniger Zeit bis zum Erreichen der vollen Belastbarkeit als erfolgreich therapierte ACell™ Patienten. PRP Patienten wurden durchschnittlich 15,6 Wochen im Schritt bewegt und erhielten 13,2 Wochen Aufbautraining, so dass sie im Durchschnitt nach 29,6 Wochen wieder ihre volle Belastbarkeit erreicht hatten. Erfolgreich therapierte ACell™ Patienten wurden durchschnittlich 20,2 Wochen im Schritt bewegt und erhielten im Anschluss im Durchschnitt 19,8 Wochen Aufbautraining, so dass sie im Durchschnitt nach 40,6 Wochen wieder ihre volle Belastbarkeit erreicht hatten. Es konnte gezeigt werden, dass die Rehabilitationsdauer bei mit thrombozytenreichem Plasma behandelten Fesselträgerschäden signifikant kürzer ist als bei mit ACell™ behandelten Fesselträgerschäden, obwohl sich das Resultat der Behandlung statistisch nicht wesentlich unterscheidet (p= 0,88). Die vielversprechenden Ergebnisse einiger ähnlich konzipierten Arbeiten konnten in der vorliegenden Studie mit keiner der angewandten Behandlungsform erreicht werden. Erwähnte Studien umfassten deutlich größere oder deutlich kleinere Patientengruppen und unterschieden sich hinsichtlich Rasse und Nutzung des Patientenmaterials sowie dem meist kürzeren Untersuchungszeitraum. Insofern erscheint einerseits eine derartige Studie aus praktischer Sicht sinnvoll und lohnenswert, andererseits zeigt sich auch der Bedarf an vergleichbaren, klinischen, praxisorientierten Arbeiten zur Evaluierung dieser Behandlungsmethoden.

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