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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.
171

Tratamento com VEGFC para revascularização linfática em membros pélvicos de camundongos / VEGFC treatment for lymphatic revascularization of mice hindlimb

Ferrão, Juliana Shimara Pires 29 July 2013 (has links)
A revascularização linfática é um desafio e o estabelecimento de novas estratégias terapêuticas podem melhorar a qualidade de vida de pessoas que sofrem de distúrbios linfáticos. O objetivo deste estudo foi verificar a capacidade de tratamento com VEGFC exógeno na melhoria da vascularização linfática de uma maneira dependente do tempo em membros pélvicos (MP) de camundongos após a remoção do linfonodo inguinal. O linfonodo inguinal esquerdo foi removido cirurgicamente para mimetizar patologias com diminuição da vascularização linfática. Densidade vascular linfática (Vv) e de comprimento (Lv) foram avaliadas por imunohistoquímica, seguidas de estereologia, após a cirurgia com ou sem o tratamento com VEGFC exógeno. O grupo controle não foi manipulado, mas recebeu soro fisiológico em vez de tratamento com VEGFC exógeno. As expressões do VEGFC e FLT4 local foram avaliadas por qPCR. Houve efeito do tempo sobre Vv e Lv no Grupo Cirurgia e diferença significativa entre os grupos Controle e Cirurgia nas três regiões estudadas (região proximal, média e distal) do MP esquerdo (MPE). A Lv mostrou diferença significativa entre os grupos Controle e Cirurgia somente na região média do MPE. A Vv e a Lv para o Grupo Tratamento foram maiores do que os outros grupos em todas as regiões do MPE. A expressão gênica do VEGFC e do FLT4 apresentou efeito do tempo em todas as regiões do MPE para os grupos Cirurgia e Tratamento. Ambas as expressões gênicas do VEGFC e do FLT4 apresentaram diferença significativa entre os grupos Controle e Cirurgia, entre os grupos Cirurgia e Tratamento e entre os grupos Controle e Tratamento. Os resultados mostraram que os camundongos são bons modelos experimentais para o uso de VEGFC exógeno como terapia de revascularização linfática, e o tratamento com VEGFC exógeno aumenta vascularização linfática já após 3 dias de dano linfático. / Lymphatic revascularization is a challenge and the establishment of new therapeutic strategies may improve quality of life from those suffering from lymphatic disorders. The objective of this study was to verify the VEGFC treatment capacity in improving lymphatic vascularization in a time-dependent manner in mouse hind limb (HL) after removal of inguinal lymphnode. The left inguinal lymphnode was surgically removed to mimetize pathologies with decreased lymphatic vascularization. Lymphatic vascular density (Vv) and length (Lv) were evaluated by immunohistochemistry followed by stereology after surgery and/or VEGFC treatment. Control group was not manipulated but received saline instead of VEGFC treatment. VEGFC and FLT4 local expression were assessed by qPCR. There was effect of time over Vv and Lv in the SG and significant difference between CG and SG in the three studied regions (proximal, medium and distal region) of the left HL (LHL). The Lv showed significant difference between CG and SG only in the medium region. The Vv and the Lv for TG were higher than the other groups in all regions of LHL. VEGFC and FLT4 gene expression presented time effect in all regions of the LHL for SG and TG. Both VEGFC and FLT4 gene expression presented significant difference between CG and SG, between SG and TG, and between CG and TG. The results show that mice are good experimental models for VEGFC use as therapy for lymphatic revascularization, and VEGFC treatment increased the lymphatic vasculature already after 3 days of lymphatic damage.
172

Perfil temporal da inflamação pulmonar induzida pela isquemia/reperfusão intestinal em ratos. Estudo do papel do sistema linfático. / Time profile of lung inflammation induced by intestinal ischemia/reperfusion in rats. Role of the lymphatic system.

Vitoretti, Luana Beatriz 17 May 2010 (has links)
A isquemia/reperfusão intestinal (I/R-i) se associa ao desenvolvimento de inflamação pulmonar aguda, que pode ser modulada por mediadores inflamatórios presentes na linfa. Avaliamos os efeitos da I/R-i sob a inflamação pulmonar e a participação do sistema linfático. Wistar machos foram submetidos a 45 min de isquemia intestinal e 24, 72 ou 120 h de reperfusão. Outro grupo teve o ducto linfático bloqueado antes da isquemia. Os resultados revelaram maior inflamação pulmonar nos animais reperfundidos por 120 h em relação aos outros períodos de reperfusão estudados. Os animais apresentaram aumento de MPO e permeabilidade. Aumento de VEGF e de IL-1<font face=\"Symbol\">&#946 e diminuição de IL-10 no explante pulmonar. Diminuição de vWf e aumento de integrina <font face=\"Symbol\">&#9461, PECAM-1 e colágeno I e IV no endotélio pulmonar. Os dados indicam que mecanismos temporais modulam a resposta inflamatória decorrente da I/R-i. Mediadores na linfa e na circulação participam do desencadeamento/manutenção da inflamação pulmonar alterando a integridade do endotélio e ativando o pulmão que libera mediadores adicionais. / Intestinal ischemia/reperfusion (i-I/R) is associated with the development of acute lung inflammation, which can be modulated by inflammatory mediators present in the lymph. We evaluated the effects of i-I/R in lung inflammation and the involvement of the lymphatic system. Wistar rats were subjected to 45 min of intestinal ischemia and 24, 72 or 120 h of reperfusion. Another group had the lymphatic duct blocked before ischemia. The results revealed greater lung inflammation in animals reperfused for 120 h in comparison to other periods studied. These animals showed increased MPO and permeability. Increased VEGF and IL-1<font face=\"Symbol\">&#946 and decreased IL-10 in lung explants. Decreased vWf and increased <font face=\"Symbol\">&#9461 integrin, PECAM-1 and collagen I and IV in the pulmonary endothelium. These data indicate that temporal mechanisms modulate the inflammatory response due to i-I/R. Mediators in the lymph and circulation participate in the initiation / maintenance of lung inflammation by altering the integrity of the endothelium and activating the lung which release additional mediators.
173

Validade do mapeamento do linfonodo sentinela na detecção de metástase linfática cervical do carcinoma papilífero da glândula tireoide / Impact of sentinel lymph node mapping to detect papillary thyroid carcinoma lymph node metastasis

Steck, José Higino 23 June 2016 (has links)
INTRODUÇÃO: O mapeamento do linfonodo sentinela (MLNS) é largamente utilizado em pacientes com melanoma cutâneo, câncer de mama e outras neoplasias malignas sólidas com a finalidade de estadiá-las e indicar esvaziamento linfático apenas na presença de metástase. Nos últimos anos aumentou o interesse pelo uso do MLNS em pacientes com carcinoma papilífero de tireoide (CPT) sem metástases linfáticas detectáveis clinicamente (estádio cN0), devido à alta frequência de metástases ocultas nesses pacientes. O MLNS pode evitar o esvaziamento linfático do compartimento central (ECC) em portadores de CPT sem metástase. Mesmo que não se planeje o ECC eletivo, o MLNS pode também ser usado para estadiar adequadamente o pescoço e indicar tratamento posterior com radioiodoterapia em casos com metástase. Esse estudo tem como objetivo verificar: 1) a efetividade da técnica do MLNS nos pacientes com CPT; 2) a acurácia do MLNS em diagnosticar as metástases linfáticas; 3) se o MLNS pode modificar o estadiamento dos pacientes com CPT cN0. MÉTODOS: Trata-se de estudo de acurácia, prospectivo longitudinal de 38 casos consecutivos de CPT clinicamente N0, atendidos em um único centro, no período de 2010 a 2015. Todos foram submetidos à tireoidectomia total, MLNS com radiofármaco e ECC eletivo. Os resultados relativos ao MLNS foram comparados com o exame anatomopatológico do conteúdo do ECC. RESULTADOS: O tempo médio de seguimento dos doentes foi de 36 ± 13 meses. Os LNS foram localizados com maior frequência nos níveis VI e III. O LNS foi detectado em 95% da casuística e os valores de avaliação de testes diagnósticos foram: 1 falso negativo, 95% de sensibilidade, 100% de especificidade, 94% de valor preditivo negativo e 97% de acurácia. O MLNS foi capaz de reestadiar 49% dos pacientes inicialmente N0 para pN positivo. Quanto ao grupo de estadiamento AJCC (que leva em conta a idade), 3% dos pacientes foram reestadiados para estádio III e 18% para estádio IV. CONCLUSÕES: 1) a técnica de MLNS utilizada nos pacientes com CPT foi efetiva em 95% dos procedimentos realizados; 2) a acurácia do MLNS em diagnosticar as metástases linfáticas cervicais foi de 97%; 3) o MLNS re-estadiou os portadores de CPT, classificados clinicamente como N0, para pN positivo em 49% da casuística, e para estádio III e IVa em 21% / INTRODUCTON: Sentinel lymph node mapping (SLNM) is widely perfomed in melanoma, breast cancer and other solid tumors, to adequately stage these diseases. More recently, the interest in SLNM for clinically N0 Papillary Thyroid Cancer (PTC) has increased due to the high rate of occult metastases in these patients, to avoid unnecessary central neck dissection (CND), and its complications. Even if routine elective CND is not planned, SLNM can be used to adequately stage the neck, and to indicate further treatment with radioiodine in cases with neck metastases, for instance. This study aims to evaluate 1) SLNM effectiveness in PTC patients, 2) SLNM accuracy to diagnosis lymph node metastases and 3) if SLNM can upstage cN0 PTC patients. METHODS: This is a prospective longitudinal, diagnostic test accuracy study with 38 consecutive cN0 PTC patients, treated in a single center between 2010 and 2015. Surgical treatment in all cases included total thyroidectomy and elective CND after SLNM. Results of SLNM were compared to CND pathological findings, in order to verify if sentinel lymph node (SLN) predicted the occurrence of PTC occult lymph node metastasis. RESULTS: The mean patients\' follow-up was 36 ± 13 months. 133 SLN were found in the neck, on levels VI and III. The SLN was identified in 95% of the patients with 1 false negative, 95% sensitivity, 94% negative predictive value and 97% accuracy. The SLNM upstaging from cN0 to pN+ was 49%, with 3% stage III and 18% stage IVa. CONCLUSION: 1) SLNM was effective in 95% of procedures, 2) SLNM accuracy was 97%, 3) SLNM upstaging from cN0 to pN+ was 49%, and to stage III and IVa was 21%
174

Pesquisa do linfonodo sentinela em pacientes portadoras de tumores de mama T3 e T4 Análise em hospital terciário oncológico e revisão sistemática da literatura. /

Oliveira Junior, Idam de January 2019 (has links)
Orientador: René Aloísio da Costa Vieira / Resumo: Introdução: O câncer de mama representa o tipo de câncer mais comum entre as mulheres no mundo. A presença e a extensão do envolvimento linfonodal axilar é um importante fator prognóstico, com grande impacto na decisão terapêutica. Por outro lado, a linfadenectomia axilar (LA) associa-se a considerável morbidade. Neste sentido, a biópsia do linfonodo sentinela (BLS) constitui modalidade atualmente aceita para uso em tumores T1 e T2, associados a axila negativa. Fato é que pacientes com tumores T3 e T4 e axila negativa são, muitas vezes, submetidas a LA de maneira desnecessária, visto o limitado número de pacientes em séries publicadas. Assim, o objetivo deste estudo é avaliar a negatividade e segurança da BLS em tumores T3 e T4, associados à axila clinicamente negativa, baseada em série de casos institucionais e revisão sistemática da literatura. Material e métodos: Estudo retrospectivo, observacional de pacientes tratadas de câncer de mama no ambulatório de Mastologia e Reconstrução Mamária do Hospital de Câncer de Barretos (HCB), Fundação Pio XII, nos anos de 2008 a 2015, realizado em pacientes portadoras de tumores T3/T4 e axila clinicamente N0 submetidas a BLS. Realizou-se, também, revisão sistemática da literatura em 5 bases. Utilizou-se a metodologia PICO, considerando P = breast cancer, I = lymph node sentinela, C = T3 and T4 tumors e O = axillary preservation. Para avaliação dos artigos, foi utilizada a metodologia PRISMA. Resultados: Foram analisadas 73 pacientes; de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: Breast cancer represents the most common type of cancer among women in the world. The presence and extent of axillary lymph node involvement represents an important prognostic factor, with an impact on therapy. On the other hand, axillary lymph node dissection (ALND) is associated with considerable morbidity. In this sense, sentinel lymph node biopsy (SLNB) is currently accepted modality for tumors T1 and T2 with negative axilla (N0). The fact is that many patients with T3-T4 tumors with negative axilla, are often submitted to unnecessarily ALND. There are limited number of patients in published series and selected cases may have axillary preservation. Thus, the objective of this study is to evaluate the negativity and safety of SLNB in T3 and T4 tumors, associated to the clinically N0, based on a series of institutional cases and a systematic review of the literature. Materials and Methods: A retrospective, observational study of patients treated for breast cancer at a tertiary cancer center between 2008 and 2015, with T3 / T4 tumors and N0 who underwent SLNB. A systematic review of literature was also carried out in 5 bases through the PICO methodology, considering: P = breast cancer; I = sentinel lymph node; C = T3 and T4 tumors and O = axillary preservation. Results: We analyzed 73 patients, 9 of whom were cT3 and after surgery they became pT2, 47 pT3 patients and 17 T4b patients. SLNB was identified in all cases and was negative for macrometastasis in 60.3%... (Complete abstract click electronic access below) / Mestre
175

Pesquisa da mutação T1799A do gene BRAF e a presença de metástases linfáticas no carcinoma papilífero da tireoide / Analysis of the T1799A BRAF mutation and lymph node mestastases in papillary thyroid carcinoma

Simone Elisa Dutenhefner 11 October 2011 (has links)
Muitos pacientes submetidos à tireoidectomia por Carcinoma Papilífero da Tireoide (CPT) têm doença linfonodal subclínica no momento da cirurgia. A mutação BRAF T17799A (V600E) é um evento comum no CPT e alguns estudos demonstram correlação entre a mutação e características de maior agressividade tumoral, incluindo a presença de metástases linfonodais. O esvaziamento eletivo do compartimento central ganha aceitação, uma vez que alguns estudos evidenciam que a presença de metástases linfonodais aumenta o risco de recidiva e mortalidade. Devido ao grande potencial de complicações do esvaziamento do compartimento central, o objetivo deste trabalho foi avaliar a associação entre a presença da mutação BRAF T17799A (V600E), a presença de metástases linfonodais e fatores clínicos e histopatológicos de pior prognóstico. Métodos: 51 casos consecutivos de pacientes com CPT foram submetidos à tireoidectomia total e ao esvaziamento eletivo ou terapêutico do compartimento central. Em todos os pacientes foi pesquisada a mutação BRAF T17799A (V600E) no tecido tireoidiano com Carcinoma Papilífero de Tireoide. Resultados: Cinquenta e quatro por cento (54,9%) dos pacientes apresentaram metástases linfonodais. Seis pacientes apresentaram metástases laterais confirmadas por punção aspirativa por agulha fina no pré-operatório e 22 pacientes (43%) apresentaram metástases não detectadas no pré ou no intra operatório A mutação BRAF T17799A (V600E) foi encontrada em 15 pacientes portadores de CPT (29,4%). A presença da mutação não teve associação estatisticamente significante para sexo, idade, tamanho do tumor, extensão extratireoidiana, multicentricidade, embolização angiolinfática e metástases linfonodais. As metástases linfonodais se associaram à multifocalidade (p = 0,005) e invasão angiolinfática (p = 0,003) na análise univariada. Conclusão: A presença da mutação BRAF T17799A (V600E) não se associou à metástases linfonodais em nosso estudo. A multifocalidade e a detecção de invasão angiolinfática no CPT foram os fatores mais importantes na predição de metástases linfonodais / Background: Many patients undergoing thyroidectomy for Papillary Thyroid Carcinoma (PTC) have subclinical node disease at the time of surgery. The BRAF T17799A (V600E) mutation is a common event in PTC and some studies have demonstrated a correlation between the mutation and aggressive characteristics including lymph node metastasis. Prophylactic Central Node Dissection (CND) is gaining acceptance in the treatment of PTC as studies have shown nodal disease increases local recurrence and may alter mortality. Given the potential complications of CND, the aim of this study was to determine the correlation among BRAF mutation, lymph node metastasis and clinical and histopathological factors of worse prognosis. Methods: A total of 51 consecutive cases of patients with PTC underwent total thyroidectomy and routine prophylactic (CND) or therapeutic neck dissection when metastases were found. All patients were tested for the BRAF mutation. Results: Overall, positive lymph nodes were found in Fifty four per cent9% of patients. Six patients had lateral metastases confirmed by fine needle aspirative cytology and 22 patients (43%) had occult metastases. The BRAF mutation was found in 15 patients (29.4%). BRAF was not correlated with sex, age, size of tumor, multifocality, extrathyroid extension or lymph node metastases. Lymph node metastases were correlated with multifocality (p = 0.005) and angiolymphatic invasion (p = 0.003) in univariate. Conclusions: The BRAF mutation was not correlated with lymph node metastases in our study. Multifocality and angiolymphatic invasion were important factors for predicting lymph node metastases
176

Minimally invasive assessment of lymphatic pumping pressure using near infrared imaging

Akin, Ryan E. 14 January 2013 (has links)
Although the major functions of the lymphatic system are fairly well defined, its vasculature has yet to be well characterized in comparison to its blood vasculature counterpart. Recent advances in optical imaging techniques have allowed for more detailed and quantitative evaluations of lymph flow dynamics and mechanism. A rat tail is often used for investigations of lymph flow because of the simple geometry, superficial nature, and disease progression models of its collecting lymphatic vessels. In this study, a pressure cuff system was fabricated and coupled with an existing functional near infrared (NIR) imaging system to measure the overall pumping pressure of the lymphatic vessels of a rat tail. In addition to adapting the system for use on rodents, previous systems used for measuring lymphatic pumping pressure in humans were improved upon in several ways. The system defined here utilizes closed-loop feedback control of pressure application at smaller, more precise intervals. Using this device, a significant difference in lymphatic vessel pumping pressure was detected between a control case and a treatment case in which a vasoactive substance with a nitric oxide donor (GTNO ointment) was applied to the tail. Although it is known that nitric oxide plays a crucial physiologic role in propagation of flow through lymphatic vessels, this study has quantified its significant pharmacological reduction of pumping pressure for the first time.
177

Untersuchung des Rinderdarmes im Hinblick auf seine Nutzung als natürliche Wursthülle und seine Einstufung als spezifiziertes Risikomaterial / Examination of bovine intestines with regard to its utilisation as natural sausage casing and its assessment as specified risk material

Zetzsche, Katrin 14 October 2010 (has links) (PDF)
Knapp 25 Jahre nach dem ersten Auftreten der bovinen spongiformen Enzephalopathie (BSE) in Europa, bleibt die Entfernung und unschädliche Beseitigung des sogenannten spezifizierten Risikomaterials (SRM) eine der wichtigsten Maßnahmen zur Reduzierung des humanen oralen BSE-Expositionsrisikos. Angesichts des Rückgangs der BSE-Inzidenzen in Europa hat sich die Europäische Kommission (EC) in ihrer „TSE Roadmap“ das Ziel gesetzt, die Auflistung und/oder die Alters-grenzen für das SRM schrittweise zu modifizieren. In diesem Sinne hat die EC die Europäische Behörde für Lebensmittelsicherheit (EFSA) mehrfach aufgefordert, das BSE-Risiko anhand aktueller Daten neu zu bewerten, insbesondere das, welches von Rindernaturdärmen für den Verbraucher ausgeht. Die wissenschaftliche Bewertung des humanen BSE-Expositionsrisikos ist jedoch bis heute mit großen Unsicherheiten verbunden und deshalb sollten erfassbare Varianzeinflüsse so weit wie möglich reduziert werden. Nachdem experimentell BSE-Infektiosität im distalen Ileum demonstriert wurde, erfolgte vorsorglich die Einstufung des gesamten bovinen Darmes (Duodenum bis Rektum, einschließlich des Mesenteriums) als SRM. Eine der wesentlichen Eingangsgrößen bei der wissenschaftlichen Bewertung des Expositionsrisikos ist die Masse des in die Nahrungskette eingebrachten potentiell infektiösen Materials. Alle bis zum heutigen Zeitpunkt durchgeführten Risikobewertungen legten eine Masse von 800 g für das bovine Ileum zugrunde. Die eigenen Untersuchungen hatten das Ziel die Gewichtsangabe des bovinen Ileums zu validieren, die Effizienz des SRM-Verbotes zur Reduktion des humanen oralen BSE-Infektionsrisikos sowie das Infektionspotential nach der Bearbeitung des Darmes im Hinblick auf seine Einstufung als SRM einzuschätzen. Von 129 Schlachtrindern wurde das Ileum unter kontrollierten Bedingungen entnommen und in der Folge der technologischen Bearbeitung vermessen. Zudem wurden 13 bovine Ilea und 11 Jejuna jeweils vor und nach der manuellen Bearbeitung histologisch auf das Vorkommen von lymphatischem Gewebe untersucht. Das lymphatische Gewebe des Darmes stellt wahrscheinlich den Ort der Erregeraufnahme nach einer oralen BSE-Infektion dar. Wesentliches Ergebnis ist ein mittleres Gewicht für das bovine Ileum im entleerten und bearbeiteten Zustand von 57 g (Spannweite: 23,1 bis 135,8 g). Dieser Wert liegt im Vergleich zu der bisher verwendeten Eingangsgröße um eine Größenordnung niedriger. Im Hinblick auf die Effizienz des SRM-Verbots zur Risikoreduktion in der Lebensmittelkette ergibt sich mit den neuen Daten ein Anstieg von 95% auf 99% für das zentrale Nervensystem (ZNS) und das ZNS-nahe periphere Nervensystem. In den histologischen Untersuchungen konnte lymphatisches Gewebe nur bei einer der bearbeiteten Ileumproben (7.7%) und zwei der bearbeite-ten Jejunumproben (18,2%) gefunden werden. Dies zeigt, dass durch die Bearbeitung der Rinderdärme der größte Teil des lymphatischen Gewebes entfernt wird. Die vorliegenden Ergebnisse stützen die Aussage anderer Studien, dass durch die Reinigung der Därme signifikante Mengen an lymphatischem Gewebe entfernt werden. Aufgrund des niedrigen Ileumgewichtes und der effektiven Entfernung des lymphatischen Gewebes kann der Anteil des Ileums an der gesamten Infektiosität, bei einem klinisch an BSE erkrankten Rind, als sehr gering eingestuft werden. Das bovine Ileum ist nach vorliegender Untersuchung lediglich mit 1 % an der Gesamtinfektiosität beteiligt und nicht, wie bisher angenommenen, mit 3,3 % bzw. 9,6 %. Angesichts dieser Ergebnisse, der aktuellen BSE-Inzidenzen in Europa, der Verteilung und Höhe der BSE-Infektiosität im bovinen Darm wird, wie auch von einer Reihe anderer Autoren, die Übertragung von BSE durch Rinderdärme als ein vernachlässigbares Risiko angesehen. Vor diesem Hintergrund sollte der SRM-Status der Rinderdärme erneut geprüft und bewertet werden. / Nearly two and a half decades after the emergence of a new transmissible spongiform encephalopathy (TSE) in bovines (BSE) in Europe the ban on so called specified risk material (SRM) remains the most important measure to reduce any potential oral human BSE exposition risk from the food chain. In view of the overall and constant reduction of the frequency of bovine TSE cases in Europe the European Commission expressed in its “TSE-road map” the need for a future lifting of the SRM-ban and the European Food Safety Authority has been repeatedly asked by the European Commission to re-assess the BSE risk for the consumer on the basis of current data, amongst others the risk associated with natural bovine sausage casings. However, the scientific evaluation of the human BSE exposition risk is impeded by great uncertainties and ascertainable variances should be reduced as far as possible. After BSE-infectivity was demonstrated experimentally for the distal bovine ileum, the whole bovine intestine from duodenum to rectum including mesentery was categorized as specified risk material (SRM).The weight of potential infective material brought into the food chain is a major influencing variable in this context. All subsequent studies concerning the human BSE exposure risk have been based on an ileum weight of 800 g per adult cattle. The aim of the own studies was to validate the existing measurement of bovine ileum and its infectivity after processing with respect to the efficiency of the SRM ban for a risk reduction in the food chain. 129 ilea were removed from slaughtered cattle and weighted during subsequent technical processing. In parallel, 13 bovine ileum and 11 jejunum samples were analyzed histologically before and after manual processing in order to detect lymphatic tissue which is presumed to be the point of entry for the infective agent. The mean weight for the whole empty and processed ileum was 57 g ranging from 23.1 g to 135.8 g. This is one order of magnitude lower than the input level used to date. Residues of lymphatic tissue were detected in one of the processed ileum samples (7.7%) and two of the jejunum samples (18.2%). This means that the major part of lymphatic tissue is removed from the bovine intestine during the different processing steps. Our results are backed up by a number of studies made by other researchers who showed that significant quantities of lymphatic tissues are removed from the bovine intestine by cleaning.The ileum has to be recognized as only a minor fraction of the total infective load per animal due to its weight and the removal of most lymphatic tissue during processing. Contrary to previous assumptions that ileum amounts to 3.3 and 9.6% respectively of the total infective tissues this study clearly shows that this premise has to be corrected to 1%. Regarding these results in combination with the decreasing BSE incidences in Europe, the distribution and the amount of the BSE infectiosity the potential BSE-infectivity represented by the bovine intestine can be considered negligible. This assessment is shared by numerous authors. A possible amendment of the current SRM status of bovine intestine should be re-assessed.
178

Sentinel node based immunotherapy of cancer /

Karlsson, Mona, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
179

Etude biomécanique in vivo de la fonction veineuse et lymphatique normale et pathologique / In vivo biomechanical evaluation of normal and pathological venous and lymphatic function in human

Mestre, Sandrine 20 September 2017 (has links)
La prise en charge de l’insuffisance veineuse chronique (IVC) et du lymphœdème repose, traditionnellement, sur des méthodes de compression fondées sur des concepts généralement admis mais insuffisamment éprouvés. Le Projet « Phlébosthène », initié en 2010, comporte le développement et l’application d’outils d’étude biomécanique quantitative de l’œdème et des troubles fonctionnels veineux. Les études n°1 et 2 reposaient sur la volumétrie par mesures étagées de circonférence du membre supérieur chez des patientes présentant un lymphœdème. Elles ont montré la valeur prédictive des variations de volume obtenues par la phase intensive du traitement décongestif quant à l’évolution du lymphœdème à moyen terme et au risque de phénomène de rebond. L’étude n°3 a validé la volumétrie de membre par caméra laser 3D chez des sujets sains et des patients souffrant d’insuffisance veineuse chronique du membre inférieur, en comparaison à la volumétrie par déplacement d’eau, méthode de référence, avec l’avantage majeur de quantifier le volume du pied et de la main. L’étude n°4 comportait, au membre inférieur, la mesure des pressions d’interface, intraveineuse, et intramusculaire sans et avec orthèse de compression dégressive de force 2 et 3, et avec orthèse de compression progressive, au repos, lors d’une manœuvre de flexion-extension du pied en position allongée, et lors d’une manœuvre de haussement sur la pointe des pieds en position debout. L’échographie avec mesure de la force d’appui sur la sonde et analyse automatique d’image calculant l’aire veineuse permettait de déterminer la courbe force / aire d’une veine superficielle et d’une veine profonde du mollet en position allongée et debout. Nous avons inclus 57 patients souffrant d’IVC (21 au stade C1s, 18 au stade C3, et 18 au stade C5 selon la classification CEAP), et 54 sujets sains témoins (18 sédentaires, 18 actifs, 18 sportifs) appariés. Les mesures de pression intraveineuse et intramusculaire ont été réalisées chez un tiers des patients et sujets sains. Le traitement des données échographiques (1776 séquences) étant en cours, nous ne pouvons présenter que des résultats préliminaires et partiels. Les pressions d’interface évoluaient conformément aux attentes, atteignant des valeurs plus élevées sous compression de force 2 que sans compression, sous compression de force 3 que de force 2, et sous compression progressive que sous compression de force 2 ou 3. La compression progressive ne se distinguait nettement des compressions dégressives qu’au niveau du mollet et non de la cheville. Les pressions d’interface étaient généralement plus élevées, sous compression, chez les témoins et les patients au stade C5, et, à un moindre degré, au stade C3, que chez les patients au stade C1s. La pression intraveineuse variait en fonction de la posture et du mouvement et était corrélée à la taille du sujet et sa longueur de jambe en orthostatisme ainsi qu’avec le stade clinique d’IVC. La pression intramusculaire évoluait parallèlement à la compression. Les boucles force / aire veineuse montraient une hystérésis caractéristique, décrivant donc la viscoélasticité des veines examinées. L’analyse complète des résultats permettra de comparer les différentes orthèses de compression et leur effet sur la biomécanique veineuse des sujets sains et pathologiques, avec des données quantitatives sur les caractéristiques viscoélastiques des veines. Nous pourrons évaluer l’effet de l’activité physique en comparant les sujets sédentaires, actifs, et sportifs. L’objectif est, à terme, de produire un modèle mathématique permettant, à partir d’un ensemble limité de données obtenues de façon non-vulnérante, de prédire l’effet des différentes modalités de compression sur la biomécanique veineuse de façon à pouvoir déterminer, grâce à la description géométrique tridimensionnelle du membre, les paramètres individuels optimaux de compression. / The conventional treatment of chronic venous insufficiency (CVI) and lymphedema is based upon mechanical compression, relying on generally admitted but insufficiently proven concepts. The " Phlebosthene " project, initiated in 2010, involves the development and implementation of innovative tools for the quantitative biomechanical evaluation of edema and venous disorders. Studies #1 and #2 were based on the calculation of the upper limb volume by serial circumference measurements in patients with lymphedema. They demonstrated the predictive value of volume variations during the intensive phase of decongestive therapy as for the medium-term outcome and the risk of rebound phenomenon. Study #3 validated segmental limb volumetry by 3D laser scanning in healthy subjects and in patients with lower limb CVI, in comparison with water displacement (reference method), with the major advantage of quantifying the volume of the foot and toes. Study #4 included the measurement, at the lower limb, of interface, intravenous, and intramuscular pressure without and with compression stockings, comparing force 2 and force 3 graduated stockings with so-called progressive compression. Measurements were performed at rest, during flexion-extension movements of the foot while the subject was lying supine, and during a tip-toe test in the standing position. Synchronously recorded B-mode sonography with automatic image analysis allowed calculating the venous area and provided force / area curves of superficial and deep calf veins in the supine and in the standing position. We included 57 patients with CVI (21 at the C1s, 18 at the C3 and 18 at the C5 stage of CVI according to the CEAP classification), and 54 matched healthy controls (18 sedentary, 18 active, 18 sportive). Intravenous and intramuscular pressure measurements were performed in one third of patients. As the processing of the 1776 B-mode sonographic sequences is still underway, we can only offer here partial and preliminary results. Interface pressures evolved as expected, reaching higher values under graduated force 2 compression stockings than without compression, under graduated force 3 than force 2 compression, and under progressive than under graduated compression. Progressive compression clearly distinguished itself from graduated compression only at the calf but not at the ankle level. Interface pressures were generally higher, under compression, in controls and in patients with IVC at the C5 stage, and, to a lesser degree, at the C3 stage, than in patients at the C1s stage. Intravenous pressure varied with posture and movement and correlated with the subject’s size and leg length in orthostatic position, and with the CVI stage. The force / area curves of superficial and deep calf veins exhibited a characteristic hysteresis, yielding viscoelasticity information. When the database will be complete and consolidated, we will be able to compare different compression stockings and their effect on the venous biomechanics of healthy and pathological subjects, providing quantitative data on the viscoelastic characteristics of superficial and deep veins. We will also be able to assess the effect of physical activity on venous biomechanics by comparing sedentary, active, and sportive subjects. The confrontation of interface, intravenous, and intramuscular pressures with these biomechanical data will provide a mathematical model using a limited set of data obtained by simple and non-invasive measurements to predict the effect of compression stockings on the biomechanics of superficial and deep veins, in order to determine, with the help of 3D laser scanning, the optimal individual compression settings.
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The Role of T Lymphocytes in the hu-PBMC-SCID Mouse Model of Epstein-Barr Virus-Associated Lymphoproliferative Disease

Cromwell, Mary A. 01 June 1995 (has links)
Epstein-Barr virus (EBV) is associated with a spectrum of benign and malignant lymphoproliferative disorders, including acute infectious mononucleosis (IM), Burkitt's lymphoma (BL) and immunosuppression-associated B cell lymphoproliferative disease (LPD). Immunosurveillance mediated by virus-specific cytotoxic T lymphocytes is believed to protect immunocompetent hosts from EBV-associated lymphoma and LPD. Due to the lack of an adequate animal model, however, the precise immunologic mechanisms which provide this protection have not been directly demonstrated in vivo. Human peripheral blood mononuclear cell-reconstituted C.B.-17-scid/scid mice (hu-PBMC-SCID mice) develop EBV-positive LPD following intraperitoneal injection of PBMC from EBV-seropositive donors. The SCID mouse disease mirrors human EBV-associated LPD in morphology, presence of the EBV genome, clonality, and patterns of expression of latent viral cellular differentiation antigens. The hu-PBMC-SCID mouse provides a unique small animal model of EBV+ LPD, and it was used in this study to examine the role of CD8+ CTL in controlling LPD. Survival time increase significantly when EBV-specific cytotoxic T-cell lines (CTL) are adoptive transferred into hu-PBMC-SCID mice, demonstrating suppression of LPD in vivoby a CTL-mediated virus-specific mechanism. Survival time also increases significantly with administration of alloreactive CTL lines, suggesting that a non-virus-specific mechanism also contributes to control of EBV-associated LPD by CTL. NOD-SCID mice reconstituted with PBMC from donors with latent EBV infection develop EBV+ LPD with significantly less frequency than do C.B.17-SCID mice reconstituted with PBMC from the same donors. Administration of anti-CD8 mAb to these mice depletes human CD8+ cells and increases the incidence of LPD to 100%, demonstrating that CD8+ T cells are neccessary for protection from EBV-associated LPD. Adoptive transfer of human CD8+ T cells, but not CD4+ T cells, prevents LPD in CD8-depleted NOD-SCID mice. In vivo depletion of CD4+ T cells prevents engraftment of human T cells, and LPD does not develop in most mice after CD4+ cell depletion. These studies are the first to directly demonstrate both the protective role of CD8+ T cells and a requirement for CD4+ T cells in EBV -associated LPD in an in vivo model.

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