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Efeitos do ultra-som terapêutico na integração de enxertos de pele total em coelhos. / Effects of the therapeutic ultrasound on the integration of full-thickness skin graft in rabbits.Adriana da Costa Gonçalves Amancio 20 February 2003 (has links)
O ultra-som terapêutico é um recurso físico muito empregado como coadjuvante na promoção do reparo tecidual. Neste trabalho, foi estudada a influência do ultra-som terapêutico na integração dos enxertos de pele total num modelo experimental em coelhos. Foram utilizados 20 coelhos adultos, fêmeas, nos quais foram realizadas cirurgias de enxerto autógeno de pele total nas regiões escapulares, pela ressecção de dois retalhos quadrados de pele de 2 cm de lado, invertendo sua posição, o enxerto retirado do lado direito sendo colocado na área receptora esquerda e vice-versa. O enxerto do lado direito era submetido ao tratamento efetivo com o ultra-som (3 MHz, 0,5 W/cm2, 5 minutos) e o enxerto do lado esquerdo, a tratamento placebo, iniciado no 3o dia pós-operatório e aplicado diariamente por sete dias. Os animais eram sacrificados no 11o dia pós-operatório e os enxertos, ressecados com uma margem de segurança, para análise histopatológica, com cortes de 5 µm. Foram obtidos cortes histológicos corados com técnicas específicas (Tricrômico de Gomori, PCNA e Picrosirius) e analisados ao microscópio de luz, sendo realizada a contagem das células em proliferação e dos vasos neoformados e a morfometria das áreas da epiderme e derme. Os resultados mostraram um significativo aumento no número de células em proliferação na epiderme e vasos neoformados na camada reticular da derme, mas isto não implicou em uma diferença entre as áreas da epiderme e derme, nos enxertos irradiados e não irradiados. Concluímos que o ultra-som terapêutico induz alterações morfológicas nos processos biológicos, como proliferação celular da camada germinativa da epiderme e neoangiogênese, envolvidos na integração de enxertos de pele total, com um potencial de aplicação clínica em humanos. / Therapeutic ultrasound is a widely used co-adjuvant physical mean to promote tissue repair. In the present investigation, the influence of therapeutic ultrasound on the integration of full-thickness skin graft was studied in rabbits. Twenty female adult rabbits were used, two 2x2 cm square-shaped full-thickness skin grafts being obtained from both scapular regions and swapped, the one cut out on the right being placed on the left and vice-versa. The graft on the right was effectively irradiated with the therapeutic ultrasound (3 MHz, 0,5 W/cm2, 5 minutes) for seven days beginning on the third postoperative day. The graft on the left was submitted to a sham irradiation. The animals were killed on the 11th day and the grafted areas were resected (graft + safety margin) for histologic examination by means of 5 µm-thick sections alternatively stained with Gomori's trichrome, PCNA and Picrosirius and examined on the light microscope. Eider proliferating cells and new blood vessels were counted, as well as the epidermic and dermic areas were measured. The results showed a significant increase in the number of epidermic proliferating cells and new blood vessels, but this did not imply any difference between the epidermic and dermic areas between irradiated and non-irradiated grafts. We conclude that the therapeutic ultrasound induces morphologic alterations in the biologic processes, as epidermic germinative layer cell proliferation and neo-angiogenesis, involved in the integration of full-thickness skin grafts and this has a potential for clinical use in humans.
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Reparação ao redor de implantes de titânio após regeneração óssea guiada com membrana reabsorvível / Healing around titanium implants after guided bone regeneration with bioresorbable membraneRodrigo Albuquerque Basilio dos Santos 26 April 2010 (has links)
O objetivo desse estudo foi descrever o padrão de reparação da ROG, após o uso de osso autógeno e membrana de colágeno suíno (BioGide). Foram utilizados 30 ratos machos Wistar, nos quais 30 mini-implantes fixaram enxerto ósseo autógeno do tipo onlay, originário de osso parietal, na região do ângulo da mandíbula. Os enxertos foram recobertos com membranas de colágeno e os animais sacrificados nos períodos de zero hora, 14, 21, 45 e 150 dias. As amostras foram descalcificadas e processadas pela técnica de fratura (Berglundh et al., 1991). Após 2 semanas, a interface entre o leito e o enxerto encontrava-se preenchida por tecido conjuntivo imaturo rico em vasos e fibroblastos. Aos 21 dias, observou-se osso neoformado sob a membrana e junto aos bordos do enxerto, integrando o enxerto ao leito. Este apresentava intensa remodelação, de modo que junto às fresas do implante observamos osso imaturo e vasos. Aos 45 dias, a estrutura colágena original da membrana apresentou avançado grau de reabsorção e diminuição da sua espessura. O tecido ósseo formado sob a membrana demonstrou início de organização lamelar. No período final, após 150 dias, o enxerto apresentou-se completamente integrado ao osso receptor e com adiantado grau de maturação. Conclui-se que após 21 dias, o osso neoformado estava em contato com o enxerto e o implante. No período de 45 dias, observou-se maturação inicial do tecido ósseo e avançada biodegradação da membrana. Apenas após 150 dias, pudemos assegurar a integração do enxerto ao osso neoformado na região do leito, com ganho adicional de tecido ósseo. / The aim of the present study was to evaluate the repair pattern after guided bone regeneration (GBR), using an autogenous bone graft covered with a porcine collagen membrane (BioGide). Thirty male Wistar rats received an onlay autogenous bone graft, harvested from parietal bone, laid on the external area near the angle of the mandible with titanium fixtures. The grafts were covered with a collagen membrane and the animals were sacrificed at 0 hour, 14, 21, 45 and 150 days. Decalcified sections were prepared according to the fracture technique (Berglundh et al., 1991). After two weeks, the bed-graft interface presented an immature connective tissue layer, containing fibroblasts-like cells and vessels. After 21 days, under the membrane, newly formed trabecular bone established bridges connecting the bed and the lateral borders of the graft. The receptor bed showed intense remodeling and adjacent to the implant threads, immature bone and vessels could be seen. After 45 days, the collagen structure of the membrane presented extensive resorption and a large decrease in thickness. The bone tissue, under the membrane, exhibited initial lamellar bone arrangement. After 150 days, a complete fusion of the graft with the receptor bed and an advanced level of bone maturity of the graft were observed. It was concluded that, after 21 days, the newly formed bone was in direct contact both with the graft and the implant. At 45 days the porcine collagen membrane showed advanced stage of resorption and an initial bone maturity could be observed. Only at 150 days, we could assure the graft integration to the newly formed bone at bed receptor area, with additional bone tissue gain.
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Avaliação do peptídeo natriurético tipo B (BNP) após transplante cardíaco pediátrico / Ventricular natriuretic B-type peptide (BNP) after pediatric heart transplantationCristina de Sylos 13 November 2008 (has links)
INTRODUÇÃO: A rejeição constitui-se em uma das principais causas de mortalidade após o transplante cardíaco pediátrico. O peptídeo natriurético tipo B (BNP), tem sido estudado como método no diagnóstico de rejeição aguda principalmente em pacientes adultos submetidos ao transplante cardíaco. OBJETIVOS: Avaliar o peptídeo natriurético tipo B no diagnóstico de rejeição aguda em crianças submetidas ao transplante cardíaco ortotópico, avaliar o papel do BNP como método adicional não invasivo na elucidação diagnóstica da doença coronariana após transplante e comparar parâmetros clínicos, ecocardiográficos e hemodinâmicos em relação à biópsia endomiocárdica no diagnóstico de rejeição cardíaca aguda. MÉTODOS: Foram coletadas 50 amostras de BNP de 33 crianças em pós-operatório de transplante cardíaco e analisados dados de idade, sexo, cor, grupo sangüíneo, painel imunológico, tempo de evolução após o transplante, sintomatologia, imunossupressão utilizada, número de rejeições, dados ecocardiográficos e parâmetros hemodinâmicos. Os grupos foram divididos em pacientes com rejeição e pacientes sem rejeição. RESULTADOS: Foram analisadas 50 amostras consecutivas de 33 crianças, durante período de 17 meses. A idade mediana foi de 10,1 anos, com predomínio do sexo feminino (54%) e da cor branca (85%). No momento da dosagem de BNP o tempo médio pós-transplante foi 4,3 anos. A biópsia endomiocárdica diagnosticou nove rejeições em oito pacientes (27%), sendo três com grau 3 A, cinco com grau 2 e um com rejeição humoral. No momento da biópsia, a maioria dos pacientes encontrava-se assintomática. O nível sérico de BNP teve mediana de 77,2 pg/ml, sendo 144,2 pg/ml no grupo com rejeição e 62,5 pg/ml no grupo sem rejeição, com p = 0,02. Análise de curva ROC mostra que níveis sangüíneos de BNP maiores que 38 pg/ml apresentam sensibilidade de 100% e especificidade de 56% na detecção de rejeição cardíaca. Os níveis de BNP foram maiores que 100 pg/ml nos pacientes com doença coronariana, com mediana de 167,5 pg/ml, em relação à 15 mediana de 40,5 pg/ml dos pacientes que não apresentaram doença coronariana. A curva ROC mostra ponto de corte de 90 pg/ml como ideal para diagnóstico de doença coronariana, com p = 0,01. Os parâmetros hemodinâmicos não foram diferentes entre os grupos com rejeição e sem rejeição. A sensibilidade do ecocardiograma para detecção de rejeição foi de 44% e especificidade de 90%, com p= 0,02. CONCLUSÕES: Pacientes podem apresentar-se assintomáticos durante episódio de rejeição aguda. O nível sérico de BNP apresentou diferença estatisticamente significante no grupo com rejeição, podendo ser método adicional no diagnóstico de rejeição cardíaca. A doença coronariana esteve associada com níveis elevados de BNP, independente da presença de rejeição aguda. O ecocardiograma mostrou baixa sensibilidade para o diagnóstico de rejeição cardíaca, mas alta especificidade. A avaliação dos parâmetros hemodinâmicos não apresentou neste estudo correlação com os resultados de biópsia. / INTRODUCTION: The rejection is one of the main causes of mortality after pediatric heart transplant. B natriuretic peptide has been used as a diagnostic method for rejection mainly in adult patients after heart transplantation. OBJECTIVE: To correlate BNP levels collected at the moment of endomyocardial biopsy with rejection, to evaluate BNP as an additional method for coronary artery disease and to compare clinical, echocardiograph assessment and hemodynamic parameters with endomyocardial biopsy findings. METHODS: There were 50 BNP blood samples from 33 children submitted to orthotopic cardiac transplantation. Analyzed parameters included: age, gender, race, blood type, reactive panel, functional class, immunosuppressive regimens, number of rejection episodes, echocardiography findings and hemodynamic parameters. The patients were divided in two groups: with rejection and without rejection. RESULTS: Thirty three children with a median age of 10.3 years (54% female) were studied at median time of 4.2 years after heart transplantation. Endomyocardial biopsy diagnosed nine rejection episodes (27%): three were grade 3A; five were grade 2 and one was humoral rejection. At the moment of biopsy most patients were asymptomatic. Average BNP level was 77.2 pg/ml (144.2 pg/ml in the patients with rejection and 65.8 pg/ml in the group without rejection, p=0.02). BNP level was increased in humoral rejection and in patients with coronary artery disease. ROC curve demonstrates BNP levels over 38 pg/ml to present 100% sensibility and 56% specificity to detect acute rejection. The levels of BNP were higher than 100 pg/ml in most of the patients with coronary artery disease (median of 167.5 pg/ml compared with a 40.5 pg/ml in patients without coronary artery disease). The curve ROC shows a critical cut off value for the diagnosis of coronary artery disease at the level of 90 pg/ml in, with p = 0.01. The hemodynamic parameters did not show significant differences between the patients with rejection and the group without rejection. The echocardiogram presented 44% sensibility and a 17 90% specificity to detect the rejection episode (p = 0.02). CONCLUSIONS: Children could be asymptomatic at allograft rejection episodes. BNP level was significantly elevated in children with the allograft rejection episode and may add a valuable information for the rejection assessment. Also, the higher BNP levels associated with coronary artery disease may contribute for its surveillance. Although the echocardiography presented low sensibility to screen for acute rejection episodes, its high specificity enhances its role to structural and functional alterations. The hemodynamic parameters did not contribute for the diagnosis nor presented correlation with the biopsy findings.
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Bypass Surgery for Lower Extremity Artery Disease: Quality Assessment of Outcome, Ultrasound Surveillance,and Follow-upRönkkö, Veera January 2021 (has links)
Introduction Bypass surgery for infrainguinal disease is indicated when a patient presents with chronic (disabling claudication or chronic limb-threatening ischaemia) or acute ischemia. Duplex ultrasound surveillance can be used in the follow-up period to detect grafts in risk of failure. If detected before occlusion occurs an intervention can prolong patency. Aim The purpose of this study was to evaluate the outcome of the procedure, whether there are factors associated with no improvement, and to elucidate the value of routine ultrasound surveillance. Methods Patients who underwent lower extremity bypass surgery at Falu hospital between 2010 and 2020 were identified from the national registry Swedvasc. Clinical outcome was based on change in the Rutherford classification. Duplex ultrasound measured peak systolic velocities. A significant stenosis was defined as a 2-3.5-fold increase in ratio of adjacent velocities in the bypass. For a non-significant stenosis, the ratio had to be increased but by less than 2 times. Results 114 patients underwent bypass surgery. Mean age was 70 years. Postoperative surveillance was carried out for 78 patients. Of these, 40 (51.3%) presented with an abnormality and further 30 of them (75%) received further intervention. There was a correlation between cardiac risk and outcome at the 30-day follow-up. For the majority of the not-surveilled, a major adverse event occurred within 1 year. Conclusions Bypass surgery was beneficial for the majority. Cardiac risk was a negative predictor for outcome. Most patients attending the surveillance benefited from early detection of risk of graft failure. To improve its value and efficacy, guidelines are needed within the clinic.
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Modélisation de la reconstitution osseuse en chirurgie de l’enfant / Bone reconstitution modelisation in paediatric cleft surgeryDissaux, Caroline 23 September 2019 (has links)
Contexte : La greffe osseuse alvéolaire est désormais considérée comme une étape clé du traitement chirurgical des fentes labio-palatines. La particularité de cette greffe réside dans sa géométrie particulière car l’os spongieux est alors placé entre deux surfaces corticales. Méthodes : L’objectif de cette recherche est d’abord d’obtenir, à l’aide d’une revue de la littérature, une meilleure compréhension de l’histoire de la greffe, des matériaux utilisés et des facteurs influençant son résultat. Ce travail se porte ensuite sur le développement d’un modèle permettant de simuler les résultats de la greffe en fonction de l’influence de différents paramètres, en particulier l’effet du compactage mécanique sur la greffe osseuse. Les caractéristiques de la greffe sont observées en fonction de la magnitude de la force appliquée (0 à 50 N). L’os spongieux fémoral et iliaque est utilisé. Une analyse par microscanner et des cultures de CFU-F sont effectuées. Résultats : Le micro-scanner permet une caractérisation précise de la structure du greffon en fonction de la force de compaction appliquée 0, 5, 20 et 50N. Le nombre de CFU-F (Colony Forming Units-Fibroblats) révèle que l’application d’une force de compaction a un impact positif sur la prolifération cellulaire. Conclusion : Cette recherche tend à mieux comprendre le remodelage osseux influencé par les forces de compaction dans le cas particulier de la fente alvéolaire, l'objectif ultime étant de guider le chirurgien vers un résultat optimisé. / Background and purpose: Alveolar cleft bone grafting is now widely accepted as one step of cleft surgical treatment. The peculiarity of this graft stands in its particular geometry: bone is placed in between two cortical surfaces. Methods: The objective of this research is first to get, trough literature, a better comprehension of graft history, graft materials and influencing factors of bone graft integration. Then this work aims to develop a model to simulate graft results according to the influence of different parameters, especially the effect of mechanical compaction on bone graft. Graft features are observed relying on magnitude of the applied force (0 to 50N). Cancellous human femoral and iliac bones are used. Micro-CT scanning and CFUs culture are performed. Results: Micro-CT scan gives a precise characterization of the structure of the graft depending of the applied compaction forces 0, 5, 20 and 50N. The number of CFUs (Colony Forming Units) shows a positive impact of compaction force on mesenchymal stem cells proliferation. Conclusion: This research tends to better understand the bone remodeling influenced by compaction forces in the alveolar cleft particular environment, with the ultimate objective to guide the surgical procedure.
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Mesenchymální kmenové buňky a jejich regenerační a imunomodulační potenciál / Mesenchymal stem cells and their regenerative and immunomodulatory potentialBrychtová, Michaela January 2016 (has links)
Mesenchymal stem cells and their regenerative and immunomodulatory potential Abstract Mesenchymal stem cells (MSCs) possess multidirectional regenerative ability, which, together with their immunomodulatory potential, makes them promising cell type for therapy of wide variety of diseases. Despite ongoing research, which proved MSCs application to be safe, reported effect of MSCs administration on patients is not convincingly beneficial yet. In our work we focused on elucidation of MSCs role in regeneration of vital organs, heart and liver, where a large damage is life threatening for patients and any improvement in therapy would save many lives. Similar situation is in Graft versus host disease (GVHD), where MSCs immunomodulatory properties could be beneficial. Role of MSCs in heart regeneration was examined in vitro. Primary adult swine cardiomyocytes (CMCs) were co-cultured with or without swine MSCs for 3 days and morphological and functional parameters (contractions, current, respiration) of CMCs were measured. MSCs showed supportive effect on CMCs survival, especially at day 3 of the experiment, where in co-culture was significantly higher number of viable CMCs with physiological morphology and maintained function. Effect of MSCs on liver regeneration was observed in swine model of chronic liver...
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Optimizing harvesting for facial lipografting with a new photochemical stimulation concept: One STEP technique™Centurión, Patricio, Gamarra, Ronald, Caballero, Gonzalo, Kaufmann, Paul, Delgado, Pia 01 December 2020 (has links)
Background: Facial fat grafting for rejuvenation is one of the most popular facial aesthetic procedures in plastic surgery. It is always challenging and since there are a lot of techniques for adipose tissue (AT) harvesting, there are no standard procedures that guarantee natural and long-lasting results. We developed the selective tissue engineering photo stimulation technique (One STEP™) in which we used a novel infrared 1210-nm wavelength laser diode for fat preserved harvesting and direct fat injection that we named PicoGraft™, with no fat manipulation. Methods: This is a retrospective descriptive study in which we included all senior author’s patients that got facial fat grafting using the One STEP™ technique. We compared the AT aspirated, after laser emission (STEP-PicoGraft) and the standard assisted liposuction samples (SAL) in cultures. We study the mitochondrial activity of the ASC between STEP and SAL in fresh samples and after 24 h. The evaluation of the results included subjective changes regarding wrinkles, grooves, palpebral bags, hyperchromic spots, and fat hypotrophy of our patients. Results: Between July 2013 and May 2018, a total of 245 patients underwent facial fat grafting using this novel technique. We observed adipocytes preserved after STEP harvesting comparing morphologic changes in SAL samples with a high concentration of inflammatory particles in cultures. ASC mitochondrial activity shows an important difference of more than 7 times in STEP samples in fresh analysis that increase 12 times in 24 h. The subjective results show a good improvement in the periorbital area. The changes on the skin and subcutaneous tissue are seen from the second month and continue to improve up to 12 months. Conclusions: Facial fat grafting using the PicoGraft™ obtained by One STEP™ technique gives excellent volumetric and regenerative results in a single treatment without volumetric hypercorrection, and it is a good alternative for facial rejuvenation. The fat graft obtained with this novel technique is homogenous, without lumps, and has high concentration of viable stimulated ADSC and a high number of viable adipocytes. Level of evidence: Level III, therapeutic study. / Revisión por pares
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Analyse der microRNA-Expression in humanen CD4+ T Zellen nach Behandlung mit dem CD4-gerichteten MAX.16H5 Antikörper in einem in vitro StimulationsmodellGlaser, Jakob 31 May 2021 (has links)
Die akute Graft-versus-Host-Krankheit (GvHD) ist eine der Hauptkomplikationen nach einer allogenen hämatopoetischen Stammzelltransplantation, die die Effizienz der Therapie und deren Einsatz limitiert. Aktuelle Präventionsstrategien und Therapien beinhalten systemisch wirkende Immunsuppressiva. Diese haben oft zahlreiche Nebenwirkungen und erhöhen die Rate von Tumorrezidiven und schweren Infektionen. Therapierefraktäre Verläufe der GvHD sind häufig und können mit einer schlechten Prognose vergesellschaftet sein. Neuartige Präventions- und Behandlungsansätze sind daher Gegenstand intensiver Forschung. Eine zentrale Rolle in der Pathogenese der akuten GvHD spielen CD4+ T Zellen. Alloreaktive T Zellen vermitteln eine proinflammatorische Immunantwort, produzieren entsprechende Zytokine und aktivieren weitere Effektorzellen. Diese Immunkaskade induziert eine systemische Entzündungsreaktion und führt zu Organ- und Gewebsschädigung. Der spezifischen Modulation dieser alloreaktiven CD4+ T Zellen hin zu einer Toleranzentwicklung gegenüber dem Empfängergewebe wird eine große Bedeutung in der Entwicklung innovativer GvHD-Präventionsstrategien beigemessen.
Es konnte in murinen Modellen gezeigt werden, dass die ex vivo-Behandlung eines allogenen bzw. xenogenen Transplantats mit dem CD4-gerichteten nicht-depletierenden Antikörper MAX.16H5 zu einer verminderten GvH-Reaktion führte. Eine Beeinträchtigung des Graft-versus-Leukämie-Effekts war nicht nachweisbar. Toleranzinduktionen durch monoklonale Antikörper gegen Oberflächenrezeptoren von Immunzellen im Rahmen von Autoimmunerkrankungen und GvHD werden in zahlreichen Studien untersucht. Darüber hinaus ist bekannt, dass in der GvHD-Pathogenese bestimmte microRNAs, 17 bis 25 Nukleotide lange, nicht kodierende, einzelsträngige RNA-Moleküle, eine Schlüsselrolle spielen. Die molekularen Mechanismen, die der Toleranzentwicklung des MAX.16H5 Antikörpers zugrunde liegen, sind jedoch nicht abschließend geklärt.
Daher war es Ziel der vorliegenden Doktorarbeit (i) ein in vitro Stimulationsmodell für weitergehende Untersuchungen am MAX.16H5 Antikörper zu etablieren und (ii) durch Quantifizierung der microRNA-Expression unter T Zellstimulierung zur Aufklärung von molekularen Mechanismen der Toleranzinduktion des Antikörpers beizutragen.
Das etablierte in vitro Stimulationsmodell diente zur Analyse und Phänotypisierung von CD4+ T Zellen nach Antikörperinkubation und Stimulation. Es konnte gezeigt werden, dass eine MAX.16H5-Behandlung zu einer verminderten Aktivierung (CD25-Expression) von T Zellen nach 24 h und 72 h in Kokultur mit murinen Milzzellen bei einem 10:1 bzw. 8,2:1 Verhältnis (humane CD4+ T Zellen zu murinen Milzzellen) führte. Dieses Modell kann als Grundlage für weitere in vitro Studien dienen, um Prozesse der Toleranzinduktion durch monoklonale Antikörper zu untersuchen, und liefert einen wichtigen Beitrag für die präklinische Analyse des MAX.16H5 Antikörpers im Hinblick auf die Entwicklung funktioneller Tests.
Weiterhin wurde in dieser Arbeit die Expression von microRNAs in CD4+ T Zellen nach Bindung des MAX.16H5 Antikörpers untersucht. Hierzu wurden humane CD4+ T Zellen mit dem MAX.16H5 Antikörper behandelt und (i) ohne Stimulation, (ii) mit murinen Milzzellen bzw. (iii) mit Phytohämagglutinin inkubiert. Das microRNA-Expressionsprofil wurde mit Next Generation Sequencing bestimmt. In dieser Screeninganalyse wurden zahlreiche microRNAs gefunden, die unter den verschiedenen Stimulationsbedingungen nach MAX.16H5-Inkubation differentiell exprimiert waren. Die Expression der miR-18a-3p und miR-598-3p wurde anschließend mit qPCR näher untersucht. Eine statistisch signifikante Regulation konnte für miR-598-3p nach 72 h Inkubation nachgewiesen werden. Es ist der bisher einzige Hinweis auf einen molekularen Effekt der MAX.16H5-Behandlung auf CD4+ T Zellen.
Ob dieser Unterschied funktioneller Natur, im Sinne eines Toleranz-induzierenden Phänotyps ist, werden zukünftige Studien zeigen. Zudem wird aktuell die miR-598-3p als potenzieller Biomarker für den Nachweis einer erfolgreichen Inkubation mit MAX.16H5 untersucht, was für zukünftige klinische Studien von großer Wichtigkeit ist.:1. Einleitung 1
1.1 Literaturübersicht 1
1.1.1 Die hämatopoetische Stammzelltransplantation 1
1.1.2 Die allogene Stammzelltransplantation 2
1.1.3 Die Graft-versus-Host-Krankheit 5
1.1.4 Die Prävention und Behandlung der akuten GvHD 8
1.1.5 Neue Strategien zur GvHD-Behandlung und -Prävention 10
1.1.6 Der Graft-versus-Leukämie-Effekt 13
1.1.7 Der CD4-gerichtete MAX.16H5 Antikörper zur Prävention der GvHD 14
1.1.8 Die Toleranzinduktion durch monoklonale Antikörper 16
1.1.9 Die microRNA 19
1.1.10 Die Rolle von miRNAs in der GvHD 20
1.1.11 Die Rationale für die Untersuchung von miR-18a-3p 21
1.1.12 Die Rationale für die Untersuchung von miR-598-3p 22
2 Fragestellung und Experimentdesign 23
3 Material und Methoden 25
3.1 Materialien 25
3.1.1 Verwendete Zellen 25
3.1.2 Geräte 25
3.1.3 Chemikalien, Medien und Reagenzien 26
3.1.4 Verbrauchsmaterialien 27
3.1.5 Oligonukleotide 28
3.1.6 Antikörper 28
3.1.6.1 Antikörper für Durchflusszytometrie 28
3.1.6.2 Antikörper für Zellinkubation 29
3.2 Methoden 29
3.2.1 Schematische Darstellung der methodischen Arbeitsschritte 29
3.2.2 Zellkulturarbeiten 31
3.2.2.1 Auftauen von Zellen 31
3.2.2.2 Konservierung von Zellen 31
3.2.2.3 Bestimmung der Zellzahl von PBMCs und Splenozyten 32
3.2.3 Isolation humaner PBMCs aus Spenderblut 32
3.2.4 Isolation muriner Milzzellen 33
3.2.5 Isolation humaner CD4+ T Zellen und MACS-Separation humaner und muriner Zellen 33
3.2.6 Inkubation mit dem murinem MAX.16H5 IgG1 Antikörper 35
3.2.7 Inkubation humaner CD4+ T Zellen 35
3.2.8 Durchflusszytometrie 36
3.2.9 RNA-Isolation 37
3.2.10 RNA-Fällung 38
3.2.11 Next Generation Sequencing von miRNAs 38
3.2.12 Next Generation Sequencing – Analyseschema 41
3.2.13 Reverse Transkription und qPCR 41
3.2.13.1 Reverse Transkription 42
3.2.13.2 qPCR 43
3.2.14 Statistische Analyse, Tabellen und Abbildungen 44
4. Ergebnisse 46
4.1 Etablierung eines in vitro Stimulationsmodells zur Analyse humaner CD4+ T Zellen nach Antikörperinkubation 46
4.2 Next Generation Sequencing zur miRNA-Expressionsanalyse in CD4+ T Zellen nach MAX.16H5 IgG1-Inkubation 50
4.2.1 FACS-Analyse isolierter CD4+ T Zellen vor und nach Antikörperinkubation 50
4.2.2 Separation muriner Milzzellen von humanen CD4+ T Zellen 53
4.2.3 NGS-miRNA-Expressionsanalyse in stimulierten und unstimulierten CD4+ T Zellen nach 72 h Inkubation 55
4.2.3.1 MiRNA-Expression nach MAX.16H5 IgG1-Inkubation und PHA-Stimulation 57
4.2.3.2 MiRNA-Expression nach MAX.16H5 IgG1-Inkubation und Stimulation mit murinen Milzzellen 59
4.2.3.3 MiRNA-Expression nach MAX.16H5 IgG1-Inkubation und ohne Stimulation 61
4.2.4 Zusammenfassung der Ergebnisse der NGS-Analyse 63
4.3 FACS-Analyse von CD4+ T Zellen nach 24 h und 72 h Inkubation 64
4.3.1 FACS-Analyse von CD4+ T Zellen nach 24 h Inkubation 64
4.3.2 FACS-Analyse von CD4+ T Zellen nach 72 h Inkubation 67
4.4 Validierung der Kandidaten-miRNA mittels qPCR 72
4.4.1 Expression von miR-18a-3p und miR-598-3p nach MAX.16H5 IgG1-Inkubation in CD4+ T Zellen nach 72 h 72
4.4.1.1 FACS-Analyse isolierter CD4+ T Zellen vor und nach Antikörperinkubation 72
4.4.1.2 FACS-Analyse der CD4+ T Zellen nach 72 h Inkubation 74
4.4.1.3 Separation muriner Milzzellen von humanen CD4+ T Zellen 78
4.4.1.4 Expression von miR-18a-3p und miR-598-3p 80
5. Diskussion 85
5.1 Die Expression von miR-18a-3p und der miR-17–92 Cluster 86
5.2 Die Expression von miR-598-3p 88
5.3 Die Differentielle Expression weiterer miRNAs 90
5.3.1 miR-223 90
5.3.2 Let-7d 91
5.3.3 miR-21 91
5.3.4 miR-181c 91
5.3.5 miR-10a 92
5.3.6 miR-150 92
5.3.7 miR-199a 92
5.3.8 miR-155 93
5.4 Die miRNA-Expressionsanalyse mit Next Generation Sequencing 93
5.5 Die Etablierung eines in vitro Stimulationsmodells 96
5.6 Verminderte T Zell-Aktivierung durch MAX.16H5 IgG1 98
6 Zusammenfassung der Arbeit 101
7 Literaturverzeichnis 104
A Erklärung über die eigenständige Abfassung der Arbeit 129
B Erklärung über die Vorbehaltlichkeit der Verfahrenseröffnung zur Verleihung des Titels Dr. med. 130
C Darstellung des wissenschaftlichen Werdegangs 131
D Danksagung 133
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Medical Therapy Versus Revascularization in Patients with Stable Ischemic Heart Disease and Advanced Chronic Kidney DiseasePaul, Timir K., Mamas, Mamas A., Shanmugasundaram, Madhan, Nagarajarao, Harsha S., Ojha, Chandra P., Jneid, Hani, Kumar, Gautam, White, Christopher J. 01 April 2021 (has links)
Purpose of Review: This article reviews the evidence on optimal medical therapy (OMT) versus coronary revascularization in patients with stable ischemic heart disease (SIHD) and advanced chronic kidney disease (CKD). Recent Findings: A post hoc analysis of the COURAGE trial in patients with SIHD and CKD showed no difference in freedom from angina, death, and nonfatal myocardial infarction (MI) between OMT and percutaneous intervention plus OMT compared with patients without CKD. The ISCHEMIA-CKD trial of 777 patients with advanced CKD revealed no difference in cumulative incidence of death or nonfatal MI at 3 years between OMT and revascularization but the composite of death or new dialysis was higher in the invasive arm. Additionally, there were no significant or sustained benefits in related to angina-related health status in invasive versus conservative strategy. Summary: An initial revascularization strategy does not reduce mortality or MI or relieve angina symptoms in patients with SIHD and advanced CKD.
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Drug-Eluting Versus Bare Metal Stents in Saphenous Vein Graft Intervention: An Updated Comprehensive Meta-Analysis of Randomized TrialsBhogal, Sukhdeep, Panchal, Hemang B., Bagai, Jayant, Banerjee, Subhash, Brilakis, Emmanouil S., Mukherjee, Debabrata, Kumar, Gautam, Shanmugasundaram, Madhan, Paul, Timir K. 01 September 2019 (has links)
Background: Drug eluting stents (DES) are preferred over bare metal stents (BMS) for native coronary artery revascularization unless contraindicated. However, the preferred stent choice for saphenous venous graft (SVG) percutaneous coronary interventions (PCI) is unclear due to conflicting results. Methods: PubMed, Clinical trials registry and the Cochrane Center Register of Controlled Trials were searched through June 2018. Seven studies (n = 1639) comparing DES versus BMS in SVG-PCI were included. Endpoints were major adverse cardiac events (MACE), cardiovascular mortality, all-cause mortality, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), in-stent thrombosis, binary in-stent restenosis, and late lumen loss (LLL). Results: Overall, during a mean follow up of 32.1 months, there was no significant difference in the risk of MACE, cardiovascular mortality, all-cause mortality, MI, stent thrombosis, TVR and TLR between DES and BMS. However, short-term follow up (mean 11 months) showed lower rate of MACE (OR 0.66 [0.51, 0.85]; p = 0.002), TVR (OR 0.47 [0.23, 0.97]; p = 0.04) and binary in-stent restenosis (OR 0.14 [0.06, 0.37]; p < 0.0001) in DES as compared with BMS. This benefit was lost on long-term follow up with a mean follow up 35.5 months. Conclusion: In this meta-analysis of SVG-PCI, DES use was associated with similar MACE, cardiovascular mortality, all-cause mortality, MI, in-stent thrombosis, TVR and TLR compared with BMS during long-term follow up. There was high incidence of MACE noted in both DES and BMS suggesting a need for exploring novel strategies to treat SVG disease to improve clinical outcomes.
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