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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.
91

Avaliação de variáveis associadas à redução do número de linfonodos em espécime cirúrgico de câncer de reto após quimiorradioterapia neoadjuvante / Evaluation of variables associated to the reduction in the number of lymph nodes in rectal cancer specimen after neoadjuvant chemoradiotherapy

Leonardo Alfonso Bustamante Lopez 03 May 2017 (has links)
Introdução: De acordo com a União Internacional Contra o Câncer um mínimo de 12 linfonodos (LN) deve ser obtido no espécime cirúrgico para o estadiamento do câncer colorretal (CCR). Estudos recentes reportaram que o uso da quimioirradioterapia neoadjuvante (QRN) pode resultar na não obtenção do número mínimo de LN na peça em 30-52% dos pacientes. Objetivo: Identificar os fatores relacionados à redução do número de LN ressecados em pacientes submetidos à neoadjuvancia e a excisão total do mesorreto. Pacientes e métodos: De janeiro de 2012 a março de 2013, 160 pacientes com câncer de reto foram submetidos à QRN (5-FU e 5040 Gys) seguida de excisão total de mesorreto com ligadura dos vasos mesentéricos inferiores nas suas raízes. Foram incluídos pacientes com estadiamento T3, T4 e/ou N+ que distavam até 10cm da borda anal e T2N0 que distavam até 7 cm da borda anal. Foram excluídos pacientes cujo tratamento com quimiorradioterapia neoadjuvante foi incompleto, ou que tiveram atrasos significativos para re-estadiamento e/ou realização da cirurgia. Todos foram estadiados através de toque retal, colonoscopia, TC de tórax e de abdome, e RM de pelve e igualmente re-estadiados 8 semanas após o término da neoadjuvância, operados e submetidos a excisão total do mesorreto. Os pacientes foram divididos em 2 grupos: A) menos de 12 LN, e B) 12 ou mais LN. Foram estudadas as possíveis variáveis relacionadas ao número de LN obtidos: sexo, idade, presença de LN acometidos, tamanho do tumor, localização da altura do tumor no reto, comprimento da peça, preservação esfincteriana, via de acesso, estadiamento inicial, grau de resposta tumoral e resposta patológica à quimiorrradioterapia neoadjuvante. Resultados: Noventa e cinco pacientes (60 masculinos) preencheram os critérios de inclusão e conseguiram ser tratados, re-estadiados e operados dentro das datas pré-estabelecidas. A média de LN ressecados foi 23,2 (3-67). Resposta patológica completa foi obtida em 18 pacientes (19%). Um mínimo de 12 LN foram obtidos em 81 pacientes (85%). Dentre os 14 doentes que obtiveram menos de 12 LN, 7 (50%) eram respostas patológicas completas. De todas as variáveis estudadas apenas resposta patológica completa na peça foi fator associado à não obtenção do número mínimo de 12 LN (p=0,002). Conclusões: Em pacientes submetidos à QRN e ETM, a resposta patológica completa foi o único fator associado a não obtenção de um mínimo de 12 de LN na peça / INTRODUCTION: According to the International Union against Cancer a minimum of 12 lymph nodes (LN) must be obtained from the surgical specimen for staging colorrectal cancer. However, recent studies reported that neoadjuvant chemoradiation may result in failure to obtain a minimum number of LN in 30-52 % of patients. OBJECTIVE: To identify factors associated with decreased number of LN resected in patients undergoing neoadjuvant therapy followed by total mesorectal excision (TEM). METHODS: From January/2012 to March/2013, 160 patients with rectal cancer underwent CRT (5 - FU and Gys 5040) followed by TEM and ligation of inferior mesenteric vessels in the roots. Patients with stage T3, T4 and/or N + within 10cm from anal verge were included. Patients with T2N0 located within 7cm from the anal verge were also included. Patients who were not able to complete the chemoradiation treatment or who presented significant delay on restaging and/or surgery were excluded from analyses. All patients were staged by digital rectal examination, colonoscopy, CT of the abdomen and chest, and MRI of the pelvis. Patients were re-staged 8 weeks after completion of neoadjuvant therapy, and submitted to total mesorectal excision right after that. Patients were stratified according to LN retrieval in two groups: A) less than 12 LN, B) 12 or more LN. Possible factors associated with the decreased number of LN were evaluated: gender, age, presence of metastatic LN, tumor size, tumor location, and length of the specimen, sphincter preservation, surgical access, initial staging, tumor regression grade and pathological response to chemoradiation. RESULTS: Ninety-five patients (60 male) met the inclusion criteria and were able to be treated, re-staged and operated within the pre-established intervals. The mean number of resected LN was 23.2 (3-67). Pathological complete response was achieved in 18 patients (19%). A minimum of 12 LN were obtained from 81 patients (85%). Half of the 14 patients with less than 12 LN presented pathologic complete response. Of all the variables studied only pathologic complete response was associated with less than 12 LN yield (p = 0.002). CONCLUSIONS: In patients submitted to chemoradiation followed by TME the complete pathological response was the only factor associated with failure to obtain a minimum of 12 LN in the specimen
92

Lokální steroidogeneze v periferních tkáních a její regulace / Local steroidogenesis in peripheral tissues and its regulation

Langová, Veronika January 2018 (has links)
The innate and adaptive immune processes are modulated by hormones including glucocorticoids and by microbiota. The exact mechanisms underlying the microbial and hormonal contributions to this control are not completely clear. Present study is therefore focused to crosstalk between microbiota and de novo biogenesis or local regeneration of glucocorticoids. In particular, the study analysed the effect of commensal microbiota on expression of genes encoding steroidogenic enzymes (Star, Cyp11a1, Hsd3b1, Cyp21a1, Cyp11b1) and regeneration of glucocorticoids (Hsd11b1) in adrenal glands, colon, spleen and mesenteric lymph nodes using conventional and germ-free mice. The expression of all 5 components of steroidogenesis was identified only in the adrenal gland and colon, whereas the lymphoid organs expressed predominantly Star, Cyp11a1 and Hsd3b1 indicating the ability to produce only progesterone but not corticosterone. Microbiota decreased the expression of Star in all studied tissues but the expression of other genes was insensitive to microbiota or did not respond homogenously depending on the tissue and gene. Hsd11b1 expression was upregulated by microbiota in the spleen but not in other tissues. Similarly, the in vitro treatment of immune cells isolated from mesenteric lymph nodes by microbial...
93

Impact of Metabolic Stress, Microbiome, and Lymph Node Colonization on <i>Salmonella</i> Shedding in Dairy Cattle

Munoz Vargas, Lohendy M. 11 August 2017 (has links)
No description available.
94

T-bet and RORa control lymph node formation by regulating embryonic innate lymphoid cell differentiation

Stehle, Christina 10 December 2021 (has links)
Angeborene lymphoide Zellen (ILCs) bilden eine Familie von Effektorzellen des angeborenen Immunsystems, denen somatisch rekombinierte Antigenrezeptoren fehlen und die in drei Hauptgruppen eingeteilt werden. In der Embryonalentwicklung spielen Typ 3 ILCs, sogenannte LTi (Lymphoid Tissue inducer) Zellen, eine zentrale Rolle in der Entwicklung von Lymphknoten. ILC3, einschließlich LTi Zellen sind abhängig von dem Master-Transkriptionsfaktor RORgt, was sich in RORgt-defizienten Mäuse durch die Abwesenheit aller ILC3, und auch durch fehlende Lymphknoten äußert. Während postnatale Ko-expression der Transkriptionsfaktoren T-bet und RORgt in ILC3-Subpopulationen fest etabliert ist, ist der Einfluss von T-bet in fötalen ILC3 und auf die Generation von Lymphknoten noch unbekannt. Um diese Mechanismen genau zu untersuchen, wurden fötale ILCs mittels Einzelzell-RNA-Sequenzierung charakterisiert, wodurch eine unerwartete Heterogenität innerhalb der ILC3 mit T-bet-exprimierenden Zellen aufgedeckt wurde. Außerdem wurden PLZF+ ILC-Vorläufer (ILCP) im sich entwickelnden Darm nachgewiesen. Weiterhin, bestätigen diverse Mausmodelle eine Schlüsselrolle für T bet in der Regulation der ILC-Differenzierung und der Entstehung von Lymphknoten. Die zusätzliche genetische Ablation von T-bet in RORgt-defizienten Mäusen beeinflusste Differenzierungsentscheidungen in fötalen ILCP und ermöglichte die Akkumulation von ILCP mit LTi-Aktivität, wodurch die Organogenese von Lymphknoten, unabhängig von RORgt wiederhergestellt wurde. PLZF+ ILCP von RORgt/T-bet-Doppeldefizienten Mäusen bestanden bis ins Erwachsenenalter, wo diese Zellen die Darmbarrierefunktionen durch Produktion von IL-22 wiederherstellten. Darüber hinaus erwies sich RORa als entscheidend für die Entwicklung von PLZF+ ILCP und die damit verbundene Bildung von Lymphknoten. / Innate lymphoid cells (ILCs) represent a family of innate effector cells lacking rearranged antigen receptors, which are classified into three main groups based on their lineage-specifying transcription factors (TF) and effector functions. During embryonic development, the formation of lymphoid organs critically relies on a specific member of group 3 innate lymphoid cells (ILC3), expressing the master transcription factor RORgt and exhibiting lymphoid tissue inducer (LTi) functions. Accordingly, RORgt-deficient mice lack ILC3 and do not generate lymph nodes (LN). While it is established that T-bet is co-expressed with RORgt in a subset of ILC3 emerging postnatally and influencing their differentiation, phenotype and functions, the effect of T-bet on fetal ILC3 biology and its impact on LN generation remains completely unknown. In order to study the role of T-bet in fetal ILC3 differentiation and functions as well as in LN formation, single-cell RNA sequencing and flow cytometry were applied to characterize fetal ILC subsets revealing an unanticipated heterogeneity within embryonic ILC3 and identifying T-bet+ ILC3 subsets within the fetal intestine and mesenteric LN anlage for the first time. Furthermore, PLZF+ ILC progenitors (ILCP) were exposed in the developing mouse intestine. Importantly, using multiple mouse models, a key role for T-bet in regulating ILC differentiation and LN formation was discovered. Specifically, additional deficiency of T-bet in RORgt-deficient mice skewed lineage fate decisions in differentiating fetal ILCP and allowed accumulation of ILCP with LTi activity, thereby rescuing LN organogenesis in a RORgt-independent fashion. PLZF+ ILCP of RORgt/T-bet double deficient mice persisted into adulthood where these cells restored intestinal barrier functions through reinstalled IL-22 production. Moreover, RORa was found to be critical for the development of PLZF+ ILCP and associated LN formation.
95

Prognostički značaj tumorske limfangiogeneze kod pacijenata sa melanomom kože / Prognostic significance of tumor lymphangiogenesis in patients with cutaneous melanoma

Špirić Zorica 10 June 2016 (has links)
<p>Увод: Туморска лимфангиогенеза је подручје активног истраживања у циљу проналаска параметара који би омогућили прецизније предвиђање понашања меланома него што то омогућавају традиционални хистолошки и клинички параметри. Иако су импресивна открића о улози лимфангиогенезе у промовисању метастазирања меланома коже, ипак су остала отворена бројна питања и још увек нису усаглашене препоруке које би биле примењиване у дијагностици и терапији. Циљ истраживања је био испитати да ли параметри лимфангиогенезе и Шилдсов индекс имају значај за прогнозу код пацијената са меланомом коже. Материјал и методе: У истраживање је укључено 100 пацијената са меланомом коже (52 без метастаза и 48 са метастазама у лимфним чворовима). За приказ ендотела лимфних судова исечци тумора су бојени имунохистохемијском методом са D2-40 антителима. Квантитативни параметри лимфангиогенезе &ndash; густина и површина лимфних судова добијени су компјутерском морфометријском анализом. За детекцију инвазије лимфних судова туморским ћелијама меланома урађено је дупло бојење D2-40 и S-100 антигена. Имунохистохемијски је испитана експресија васкуларног ендотелног фактора раста (VEGF)-C и VEGF-D у туморским ћелијама, макрофагима и фибробластима меланома. Шилдсов индекс је рачунат као логаритам производа дебљине меланома, квадриране перитуморске густине лимфних судова (ГЛС) и броја 2 за присутну лимфатичну инвазију. Резултати: Параметри који су статистички значајно доприносили појави метастаза меланома у лимфним чворовима, на униваријантној анализи, били су интратуморска ГЛС, перитуморска ГЛС, експресија VEGF-C и VEGF-D у туморским ћелијама, дебљина тумора, улцерација, дубља инвазија по Кларку, нодуларни тип меланома и мушки пол. Мултиваријантна анализа је показала да су значајни независни прогностички фактори за настанак метастаза позитивна експресија VEGF-C у туморским ћелијама, повећана дебљина тумора, повећана интратуморска ГЛС и перитуморска ГЛС. Као најјачи предиктор појаве метастаза показала се позитивна експресија VEGF-C у туморским ћелијама. Пацијенти са &lt;20% VEGF-C позитивних туморских ћелија имали су 20 пута већи ризик за развој метастаза него пацијенти са негативном експресијом. Параметри са утицајем на меланом-специфично преживљавање на униваријантној анализи су били интратуморска ГЛС, перитуморска ГЛС, експресија VEGF-C и VEGF-D у туморским ћелијама, док је мултиваријантна анализа издвојила повећану интратуморску и перитуморску ГЛС као независне факторе ризика за смртни исход. Интратуморска и перитуморска површина лимфних судова, лимфатична инвазија и експресија VEGF-C и VEGF-D у макрофагима и фибробластима нису биле значајно повезане са појавом метастаза нити са краћим меланом-специфичним преживљавањем. Ниједан параметар лимфангиогенезе није био значајно повезан са краћим преживљавањем без рецидива болести. Анализа оперативне карактеристичне криве (ROC) је показала да је Шилдсов индекс веома добар параметар за процену настанка метастаза, са сензитивношћу 81,3% и специфичношћу 75%. Већа површина испод ROC криве код Шилдсовог индекса (0,857) у поређењу са површином код других параметара, указује да је индекс најтачнији прогностички параметар за настанак метастаза, затим следи интратуморска ГЛС (површина 0,795), перитуморска ГЛС (површина 0,772), дебљина меланома (површина 0,762) и American Joint Committee on Cancer систем класификације (површина 0,752). Закључак: Истраживање туморске лимфангиогенезе идентификује нове параметре као значајније предикторе исхода болести од дебљине тумора, улцерације и осталих клиничко-патолошких параметара. Помоћу интратуморске и перитуморске ГЛС, експресије VEGF-C и VEGF-D у туморским ћелијама, као и прорачуна Шилдс индекса, може се предвидети метастатски капацитет меланома. Рутинска патохистолошка анализа меланома требало би да укључи квантитативну анализу мреже лимфних судова и семиквантитативну евалуацију експресије VEGF-C и VEGF-D у туморским ћелијама.</p> / <p>Uvod: Tumorska limfangiogeneza je područje aktivnog istraživanja u cilju pronalaska parametara koji bi omogućili preciznije predviđanje ponašanja melanoma nego što to omogućavaju tradicionalni histološki i klinički parametri. Iako su impresivna otkrića o ulozi limfangiogeneze u promovisanju metastaziranja melanoma kože, ipak su ostala otvorena brojna pitanja i još uvek nisu usaglašene preporuke koje bi bile primenjivane u dijagnostici i terapiji. Cilj istraživanja je bio ispitati da li parametri limfangiogeneze i Šildsov indeks imaju značaj za prognozu kod pacijenata sa melanomom kože. Materijal i metode: U istraživanje je uključeno 100 pacijenata sa melanomom kože (52 bez metastaza i 48 sa metastazama u limfnim čvorovima). Za prikaz endotela limfnih sudova isečci tumora su bojeni imunohistohemijskom metodom sa D2-40 antitelima. Kvantitativni parametri limfangiogeneze &ndash; gustina i površina limfnih sudova dobijeni su kompjuterskom morfometrijskom analizom. Za detekciju invazije limfnih sudova tumorskim ćelijama melanoma urađeno je duplo bojenje D2-40 i S-100 antigena. Imunohistohemijski je ispitana ekspresija vaskularnog endotelnog faktora rasta (VEGF)-C i VEGF-D u tumorskim ćelijama, makrofagima i fibroblastima melanoma. Šildsov indeks je računat kao logaritam proizvoda debljine melanoma, kvadrirane peritumorske gustine limfnih sudova (GLS) i broja 2 za prisutnu limfatičnu invaziju. Rezultati: Parametri koji su statistički značajno doprinosili pojavi metastaza melanoma u limfnim čvorovima, na univarijantnoj analizi, bili su intratumorska GLS, peritumorska GLS, ekspresija VEGF-C i VEGF-D u tumorskim ćelijama, debljina tumora, ulceracija, dublja invazija po Klarku, nodularni tip melanoma i muški pol. Multivarijantna analiza je pokazala da su značajni nezavisni prognostički faktori za nastanak metastaza pozitivna ekspresija VEGF-C u tumorskim ćelijama, povećana debljina tumora, povećana intratumorska GLS i peritumorska GLS. Kao najjači prediktor pojave metastaza pokazala se pozitivna ekspresija VEGF-C u tumorskim ćelijama. Pacijenti sa &lt;20% VEGF-C pozitivnih tumorskih ćelija imali su 20 puta veći rizik za razvoj metastaza nego pacijenti sa negativnom ekspresijom. Parametri sa uticajem na melanom-specifično preživljavanje na univarijantnoj analizi su bili intratumorska GLS, peritumorska GLS, ekspresija VEGF-C i VEGF-D u tumorskim ćelijama, dok je multivarijantna analiza izdvojila povećanu intratumorsku i peritumorsku GLS kao nezavisne faktore rizika za smrtni ishod. Intratumorska i peritumorska površina limfnih sudova, limfatična invazija i ekspresija VEGF-C i VEGF-D u makrofagima i fibroblastima nisu bile značajno povezane sa pojavom metastaza niti sa kraćim melanom-specifičnim preživljavanjem. Nijedan parametar limfangiogeneze nije bio značajno povezan sa kraćim preživljavanjem bez recidiva bolesti. Analiza operativne karakteristične krive (ROC) je pokazala da je Šildsov indeks veoma dobar parametar za procenu nastanka metastaza, sa senzitivnošću 81,3% i specifičnošću 75%. Veća površina ispod ROC krive kod Šildsovog indeksa (0,857) u poređenju sa površinom kod drugih parametara, ukazuje da je indeks najtačniji prognostički parametar za nastanak metastaza, zatim sledi intratumorska GLS (površina 0,795), peritumorska GLS (površina 0,772), debljina melanoma (površina 0,762) i American Joint Committee on Cancer sistem klasifikacije (površina 0,752). Zaključak: Istraživanje tumorske limfangiogeneze identifikuje nove parametre kao značajnije prediktore ishoda bolesti od debljine tumora, ulceracije i ostalih kliničko-patoloških parametara. Pomoću intratumorske i peritumorske GLS, ekspresije VEGF-C i VEGF-D u tumorskim ćelijama, kao i proračuna Šilds indeksa, može se predvideti metastatski kapacitet melanoma. Rutinska patohistološka analiza melanoma trebalo bi da uključi kvantitativnu analizu mreže limfnih sudova i semikvantitativnu evaluaciju ekspresije VEGF-C i VEGF-D u tumorskim ćelijama.</p> / <p>Introduction: Tumor lymphangiogenesis is a field of active research with the aim of finding parameters which would enable the more precise prediction of melanoma behavior in comparison to the prediction of traditional histological and clinical parameters. Although scientific findings about the role of lymphangiogenesis in developing cutaneous melanoma are impressive, there are unresolved questions and recommendations to be applied in diagnostics and therapy, which are still not in compliance. The aim of this research is to examine if parameters of lymphangiogenesis and the Shields Index are important for the prognosis in patients with cutaneous melanoma. Material and methods: The research included a hundred patients with cutaneous melanoma (52 without metastasis and 48 with metastasis of lymphatic nodes). To present endothelial lymphatic vessels, specimens were stained by an immunohistochemical method with D2-40 antibodies. Quantitative parameters of lymphangiogenesis &ndash; lymphatic vessel density (LVD) and area (LVA) were calculated by computer-assisted morphometric analysis. In order to detect the invasion of lymphatic vessels by melanoma tumor cells, a double staining of D2-40 and S-100 antigens was performed. The expression of vascular endothelial growth factor (VEGF)-C and VEGF-D was tested by an immunohistochemical method in tumor cells, macrophages and fibroblasts melanoma. The Shields Index was calculated as a logarithm by multiplying the melanoma thickness, square of peritumoral LVD and the number 2 for present lymphatic invasion. Results:Parameters that statistically had a significant contribution to the emergence of melanoma metastases in lymph nodes, during the univariate analysis, were intratumoral LVD, peritumoral LVD, VEGF-C and VEGF-D expression in tumor cells, tumor thickness, ulceration, deeper Clarkꞌs level of invasion, nodular type of melanoma and a male sex. The multivariate analysis showed that positive expression of VEGF-C in tumor cells, tumor thickness, increased intratumoral LVD and peritumoral LVD are significant independent prognostic factors. The most important predictor of metastases is a positive expression of VEGF-C in tumor cells. Patients with &lt;20% VEGF-C positive tumor cells were 20 times more at risk of developing metastases than patients with a negative expression. Parameters that influence melanoma-specific survival at the univariate analysis were intratumoral LVD, peritumoral LVD, VEGF-C and VEGF-D expression in tumor cells, while the multivariate analysis singled out an increased intratumoral and peritumoral LVD as independent factors of the death risk. Intratumoral and peritumoral LVA, lymphatic invasion and VEGF-C and VEGF-D expression in macrophages and fibroblasts were not significantly correlated either with the emergence of metastases or with melanoma-specific survival. Non-parameter of lymphangiogenesis was significantly related with shorter disease-free survival. The analysis of receiver operator characteristic (ROC) curve showed that the Shields Index is a very good parameter for the estimation of the appearance of metastases, with the sensitivity of 81.3% and specificity of 75%. A bigger area under the ROC curve with the Shields Index (0.857) in comparison to the area in other parameters shows that the index is the most accurate prognostic parameter for an emergence of metastases, followed by intratumoral LVD (area 0.795), peritumoral LVD (area 0.772), the thickness of melanoma (area 0.762), and the American Joint Committee on Cancer classification system (area 0.752). Conclusion: The research of tumor lymphangiogenesis identifies new parameters as significant predictors of the disease outcome more so than the parameters like tumor thickness, ulceration, and other clinical-pathological parameters. By intratumoral and peritumoral LVD, VEGF-C and VEGF-D expression in tumor cells, as well as by the calculation of Shields Index, metastatic capacity of melanoma can be predicted. A routine pathohistological analysis of melanoma should include quantitative analysis of the lymphatic vessels network and semiquantitative evaluation of VEGF-C and VEGF-D expression in tumor cells.</p>
96

Magnetnorezonantna sekvenca difuzionog kretanja u proceni metastatske invazije limfnih čvorova kod malignih tumora ženskih polnih organa / Diffusion-weighted magnetic resonance imaging for evaluation of malignant lymph node invasion in patients with female genital neoplasms

Basta Nikolić Marijana 15 September 2016 (has links)
<p>UVOD: Maligni tumori reproduktivnih organa nalaze se među vodećim uzrocima obolevanja i umiranja od malignih bolesti žena, kako u svetu, tako i u Srbiji. Jedan od najvažnijih puteva &scaron;irenja ovih bolesti je limfogeni, a konvencionalna radiolo&scaron;ka dijagnostika limfnih čvorova kod ovih pacijentkinja je neprecizna. Funkcionalna radiolo&scaron;ka dijagnostika, uključujući i magnentno rezonantnu sekvencu difuzionog kretanja (DWI) i iz nje izvedenu ADC mapu koja omogućava kvantitativnu analizu difuzionih osobina unutar limfnog čvora, daju obećavajuće rezultate u mogućnosti razlikovanja benignih od maligno izmenjenih limfnih čvorova male karlice i ingvinuma kod pacijentkinja obolelih od malignih tumora ženskih polnih organa. CILJ: Cilj studije je 1. utvrđivanje dijagnostičkih mogućnosti magnetnorezonantne sekvence difuzionog kretanja (DWI) u razlikovanju benignih od maligno izmenjenih limfnih čvorova male karlice i ingvinuma kod pacijentkinja obolelih od malignih tumora ženskih polnih organa, poređenjem preoperativno načinjenog magnetnorezonantnog pregleda i postoperativnog patohistolo&scaron;kog nalaza; 2. analiza povezanosti osobina metastatski izmenjenih limfnih čvorova na sekvenci difuzionog kretanja (DWI) i gradusa primarnog tumora, i 3. utvrđivanje uticaja tehničkih karakteristika sekvenci difuzinonog kretanja (DWI) na magnetnorezonantu procenu metastatske infiltracije karličnih i ingvinalnih limfnih čvorova i postoperativnog patohistolo&scaron;kog nalaza. MATERIJAL I METODE: Istraživanje je sprovedeno u periodu od 2013. do 2016.godine, kao prospektivna klinička studija u Centru za radiologiju, na Operativnom odeljenju Zavoda za ginekologiju, Klinike za ginekologiju i aku&scaron;erstvo i u Zavodu za patologiju Kliničkog Centra Vojvodine u Novom Sadu. Studija je obuhvatila 80 pacijentkinja obolelih od malignih tumora vulve, vagine, grlića materice, tela materice i jajnika. Na osnovu lokalizacije malignog tumora sve ispitanice su razvrstane u 5 grupa: grupa A- 3 žene obolele od carcinoma vulve, grupa B- 1 žena obolela od karcinoma vagine, grupa C-32 pacijentkinje obolele od karcinoma grlića materice, grupa D- 30 pacijentkinja obolelih od malignih tumora tela materice i grupa E- 14 žena obolelih od malignih tumora jajnika. Procena stadijuma bolesti definitivno je izvr&scaron;ena posle operacije na osnovu histopatolo&scaron;kog pregleda kompletnog hirur&scaron;kog materijala uključujući i pregled uklonjenih limfnih čvorova na osnovu aktuelne FIGO klasifikacije stadijuma bolesti zasebno za svaku pojedinačnu lokalizaciju malignog tumora. Svim pacijentkinjama je preoperativno načinjen magnetnorezonantni pregled male karlice na uređaju za magnetnu rezonancu 1.5 T General Electric Signa HDx u Centru za radiologiju, Kliničkog centra Vojvodine. Kod istih pacijentkinja naknadno je sprovedeno standardno hirur&scaron;ko lečenje po protokolu hirur&scaron;kog lečenja za dato maligno ginekolo&scaron;ko oboljenje sa karličnom i/ili ingvinalnom limfadenektomijom. Postoperativno je izvr&scaron;ena patohistolo&scaron;ka analiza hirur&scaron;ki uklonjenog materijala i limfnih čvorova razdvojenih po anatomskim grupama u karlici i ingvinalnoj regiji. REZULTATI: Ukupno 2320 limfnih čvorova je mapirano i patohistolo&scaron;ki pregledano kod 80 pacijenata. Metastaze u limfnim čvorovima patohistolo&scaron;ki su verifikovane kod 28 pacijenata (35%). Kod ovih 28 (35%) pacijentkinja, 152 (27,28%) od ukupno 557 limfnih čvorova bilo je metastatski izmenjeno na patohistolo&scaron;kom pregledu. Metastaze u limfnim čvorovima utvrđene su kod 2 pacijentkinje (7,14%) sa karcinomom vulve, 11 (39,28%) sa karcinomom cerviksa, 9 (32,14%) sa tumorima tela materice, te 6 (21,42%) sa tumorima jajnika. Od 28 pacijentkinja kod kojih su utvrđeni pozitivni limfni čvorovi, 14 pacijentkinja (50%) imalo je dobro diferentovan primarni tumor, 8 (28,57%) srednje diferentovan, dok je 6 (21,42%) imalo lo&scaron;e diferentovan primarni tumor. Od ukupno 152 metastatski izmenjena limfna čvora u na&scaron;oj studiji, 8 limfnih čvorova (5,26%) pripadalo je ingvinalnoj grupi od čega 5 (3,289%) povr&scaron;noj ingvinalnoj, a 3 ( 1,97%) dubokoj ingvinalnoj grupi, 8 (5,26%) parametrijalnoj grupi, 48 (31,58%) opturatornoj grupi, 40 (26,31%) spolja&scaron;njoj ilijačnoj grupi, 36 (23,684%) unutra&scaron;njoj ilijačnoj grupi, dok je 12 (7,89%) pripadalo zajedničkoj ilijačnoj grupi karličnih limfnih čvorova. Kraći prečnik limfnog čvora nije pokazao značajnu razliku između metastatskih ( mean &plusmn; SD, 8,3 &plusmn; 5.4 mm, raspon , 4.5-30 mm ) i limfnih čvorova koji nisu bili metastatski izmenjeni ( 6,3 mm &plusmn; 1,5 , 4,5-9,6 mm ; P= 0,191 ). Izmerena ADC vrednost bila je značajno niža kod metastatski izmenjenih limfnih čvorova (mean &plusmn; SD , ADC: 0,8725 x 10-3 mm2/s &plusmn; 0,0125) nego kod limfnih čvorova koji nisu bili metastatski izmenjeni (mean &plusmn; SD, ADC: 1,116 x 10- 3 mm2/s &plusmn; 0,1848; P=0,001). Prosečne vrednosti ADC kod b =800 s/mm2 i b =1200 s/mm2 nisu se značajno razlikovale između metastaski izmenjenih limfnih čvorova (mean &plusmn; SD, ADC: 0,8575 &plusmn; 0,0125 x 10-3 mm2/s, ADC:0,8859 &plusmn; 0,0125 x 10-3 mm2/s) i limfnih čvorova koji nisu metastatski izmenjeni (mean &plusmn; SD, ADC:1,0345 &plusmn; 0,1222 x 10-3 mm2/s, ADC:1,1125 &plusmn; 1638 x 10-3 mm2/s; P =0,657 i P = 0,877). Ako se koristi vrednost ADC od 0,860 x 10- 3 mm2 / s kao kritična vrednost za razlikovanje metastatskih od limfnih čvorova koji nisu metastatski izmenjeni, senzitivnost DWI MR iznosila je 89%, specifičnost 85% i ukupna tačnost 86%. Pozitivna prediktivna vrednost (PPV) DWI MR u detekciji limfnih metastaza u karličnoj i ingvinalnoj regiji iznosila je 30%. Negativna prediktivna vrednost (NPV) testa iznosila je 99%. Pozitivna prediktivna vrednost (PPV) MR zasnovana na kriterijumu ADC vrednosti značajno je veća u odnosu na sve kriterijuma veličine (P &lt; 0,001). Negativna prediktivna vrednost MR zasnovanoj na kriterijumima veličine limfnog čvora i na ACD vrednosti nisu se međusobno statistički značajno razlikovali (P&lt;0,05). Performanse dijagnostičke metode (MR) bile su značajno bolje za minimalnu ADC vrednost od svih kriterijuma baziranih na veličini limfnih čvorova ( P=0.001 za minimalnu ADC vrednost u odnosu na sve druge kriterijume). MRI na osnovu definisanog modela koji kombinuje kriterijum ADC vrednosti sa kriterijumom veličine ima sledeće dijagnostičke performanse za diferencijaciju malignih od benignih limfnih čvorova: senzitivnost od 95%, specifičnost 92%, sveukupna tačnost od 92,5%, pozitivnu prediktivnu vrednost od 46% i negativnu prediktivnu vrednost od 99.6%. ZAKLJUČAK: Kriterijum veličine limfnog čvora nije dovoljno precizan pokazatelj metastatske invazije limfnih čvorova. Sekvenca difuzionog kretanja (DWI) uvek se mora analizirati zajedno sa ADC mapom i visoko rezolutivnim T1 i T2 otežanim magnetnorezonantnim sekvencama. Studijom je dokazan visok stepen povezanosti između preoperativnog određivanja metastaske infiltracije karličnih i ingvinalnih limfnih čvorova malignih tumora ženskih polnih organa primenom sekvence difuzionog kretanja (DWI) i postoperativnog patohistolo&scaron;kog nalaza. Uz graničnu ADC vrednost od 0,860 x 10-3 mm2/ s, senzitivnost MRI DWI u otkrivanju metastatskih limfnih čvorova iznosi 89%, a specifičnost 85%. Kombinacija ADC vrednosti i morfolo&scaron;kih karakteristika limfnih čvorova konvencionalnim magnentno rezonantnim pregledom je najprecizniji prediktor postojanja metastatske infiltracije karličnih i ingvinalnih limfnih čvorova kod pacijentkinja sa malignim tumorima ženskih polnih organa. Tehničke karakteristike sekvenci difuzionog kretanja (DWI) u smislu razlike u visokim b vrednostima ne utiču na magnentno rezonantnu procenu metastatske infiltracije karličnih i ingvinalnih limfnih čvorova kod pacijentkinja sa malignim tumorima ženskih polnih organa. Studijom nije utvrđena statistički značajna razlika između preoperativno utvrđenih ADC vrednosti metastatski izmenjenih limfnih čvorova i stepena histolo&scaron;ke diferencijacije ovih tumora. Sekvenca difuzionog kretanja (DWI) je brza, jednostavna, neinvazivna metoda koja značajno doprinosi dijagnostičkim mogućnostima magnetne rezonance u razlikovanju benignih od malignih limfnih čvorova male karlice i ingvinuma.</p> / <p>INTRODUCTION: Malignant tumors of reproductive organs are among the leading causes of morbidity and mortality in women, both in Serbia and worldwide. Lymphatic spread is one of the most important pathways of tumor dissemination. However, conventional lymph node imaging in these patients is imprecise. Functional imaging, including diffusion-weighted magnetic resonance imaging (DWI MRI) and derived ADC map which allows quantitative analysis of diffusion parameters within a lymph node, provide promising results in discrimination benign from malignant pelvic and inguinal lymph nodes in patients with gynecological malignancies. AIM: Aim of the study was: 1. To assess diagnostic performances of DWI MRI in differentiation between benign and malignant pelvic and inguinal lymph nodes in patients with gynecological malignancies, by comparison of preoperative magnetic resonance and postoperative histopathological findings. 2. To analyze correlation between DWI characteristics of metastatic lymph nodes and grade of the primary tumor, and 3. To evaluate the influence of technical characteristics of DWI sequences on MR assessment of metastatic pelvic and inguinal lymph node and postoperative histopathological findings. MATERIAL and METHODS: The prospective clinical study was conducted in Center for Radiology, Surgery Department of Clinic for Gynecology and Obstetrics and Pathology Department of Clinical Center of Vojvodina from 2013 to 2016. It comprised 80 patients with malignant tumors of vulva, vagina, uterine cervix and body and ovaries. Based on the localization of the tumor, all patients were divided into 5 groups: group A-3 patients with vulvar cancer, group B- 1 patient with vaginal cancer, group C- 32 patients with cervical cancer, group D- 30 patients with uterine body tumors and group E- 14 patients with malignant ovarian tumors. Staging of the disease was performed after surgery based on histopathological examination of complete surgical specimen, including examination of removed lymph nodes, based on current FIGO classification separately for each primary tumor location. Preoperatively, all patients underwent MRI examination (1.5 T General Electric Signa HDx) at Center for Radiology, Clinical Center of Vojvodina. The same patients underwent standard surgical treatment according to the treatment protocol regarding the tumor type and stage, with complete pelvic and/or inguinal lymphadenectomy. Histopathological examination of surgically removed material and lymph nodes separated in pelvic and inguinal anatomic groups was performed after the surgery. RESULTS: The total of 2320 of lymph nodes were mapped and histopathologically examined in 80 patients included in the study. Metastases in lymph nodes were histopathologically confirmed in 28 patients (35%). In these 28(35%) patients, in 152 (27,28%) out of 557 lymph nodes histopathological examination confirmed metastases. Lymph node metastases were confirmed in 2 patients (7.14%) with vulvar cancer, 11 (39.28%) with cervical cancer, 9 (32.14%) with uterine body tumors and 6 (21.42%)patients with ovarian tumors. In 28 patients with positive lymph nodes, 14 patients (50%) had well differentiated primary tumor, 8 (28.57%) moderately differentiated, while 6 (21.42%) patients had poorly differentiated primary tumor. Out of 152 metastatic lymph nodes in our study, 8 lymph nodes (5.26%) were inguinal ( 5 (3.289%) superficial inguinal and 3 ( 1.97%) deep inguinal group), 8 (5.26%) were parametrial, 48 (31. 58%) obturatory, 40 (26.31%) external iliac, 36 (23.684%) internal iliac, while 12 (7. 89%) belonged to common iliac pelvic lymph nodes group. Shorter lymph node axis did not show significant difference between metastatic ( mean &plusmn; SD, 8.3 &plusmn; 5.4 mm, range , 4.5-30 mm ) and benign lymph nodes ( 6.3 mm &plusmn; 1.5 , 4.5-9.6 mm ; P= 0.191 ). Measured ADC values were significantly lower in metastatic (mean &plusmn; SD , ADC: 0.8725 x 10-3 mm2/s &plusmn; 0.0125) than benign lymph nodes (mean &plusmn; SD, ADC: 1.116 x 10-3 mm2/s &plusmn; 0.1848; P=0.001). Mean ADC values at b =800 s/mm2 and b =1200 s/mm2 did not differ significantly between metastatic (mean &plusmn; SD, ADC: 0.8575 &plusmn; 0.0125 x 10-3 mm2/s, ADC:0.8859 &plusmn; 0,0125 x 10-3 mm2/s) and benign lymph nodes (mean &plusmn; SD, ADC:1.0345 &plusmn; 0.1222 x 10-3 mm2/s, ADC:1.1125 &plusmn; 1638 x 10-3 mm2/s; P =0.657 i P = 0.877). If ADC value of 0.860 x 10- 3 mm2 / s is determined as a cut off value for discrimination of benign and malignant lymph nodes, DWI MRI sensitivity was 89%, specificity 85% and overall accuracy was 86%. Positive predictive value (PPV) of DWI MR in detection of pelvic and inguinal lymph node metastases was 30%. Negative predictive value (NPV) of the test was 99%. MRI PPV based on ADC value criteria was significantly higher compared to all size-based criteria (P &lt; 0,001). MRI NPV based on size based and ADC values criteria did not differ significantly (P&lt;0,05). Performances of diagnostic method (MRI) were significantly better for minimal ADC value compared to all lymph node size-based criteria ( P=0.001 for minimal ADC value compared to all other criteria). Combination of ADC value criteria and size-based criteria yields MRI the following diagnostic performances in discrimination between benign and malignant lymph nodes: sensitivity 95%, specificity 92%, overall accuracy 92.5%, positive predictive value 46% and negative predictive value 99.6%. CONCLUSION: Lymph node size is not sufficiently precise criteria for determination of metastatic lymph node involvement. DWI sequence always needs to be evaluated together with ADC map and high resolution T1W and T2W magnetic resonance sequences. The study shows high correlation between preoperative assessment of pelvic and inguinal lymph node metastases from gynecological malignancies using MRI DWI and postoperative histopathological findings. With a cut off ADC value of 0.860 x 10-3 mm2/ s, sensitivity of MRI DWI in metastatic lymph node detection is 89%, while specificity is 85%. Combination of ADC values and morphological lymph nodes characteristics assessed by conventional MRI is the most precise predictor of metastatic pelvic and inguinal lymph node invasion in patients with gynecological malignancies. Technical characteristics of DWI i.e. different high b-values do not influence MR assessment of metastatic pelvic and inguinal lymph node involvement in patients with gynecological malignancies. The study did not confirm statistically significant difference between preoperatively measured ADC valued of metastatic lymph nodes and histological grade of primary tumors. DWI MRI sequence is fast, simple, noninvasive method which aids significantly to MRI diagnostic performances in discrimination between benign and malignant pelvic and inguinal lymph nodes.</p>
97

Impacto da solução de Carnoy no número de linfonodos resgatados em peças cirúrgicas de câncer gástrico: estudo prospectivo randomizado / Impact of Carnoy\'s solution in lymph node retrieval following D2 gastrectomy for gastric cancer: prospective randomized trial

Dias, Andre Roncon 25 August 2014 (has links)
Introdução: O adenocarcinoma gástrico é uma doença de elevada incidência e alta mortalidade. A gastrectomia com linfadenectomia é tratamento potencialmente curativo, promovendo controle loco-regional da doença e fornecendo material para análise histopatológica. Para o adequado estadiamento dos pacientes é recomendado que pelo menos 16 linfonodos sejam examinados pela patologia, entretanto, espera-se maior sobrevida quando >= 30 linfonodos são avaliados, mesmo em pacientes com tumores precoces. A justificativa para este achado é o sub-estadiamento de pacientes com poucos linfonodos examinados. Linfonodos pequenos são particularmente difíceis de serem encontrados, mas podem conter metástases e impactar negativamente na sobrevida. Visando facilitar sua identificação, soluções clareadoras de gordura foram propostas, entretanto não há evidência clara de seu benefício clínico. Objetivos: Comparar as soluções de Carnoy e de formalina neutra tamponada em relação ao número absoluto de linfonodos encontrados na peça cirúrgica de pacientes submetidos a gastrectomia. Averiguar se linfonodos retirados cirurgicamente são perdidos com a fixação em formalina e, caso isso ocorra, se este fato é relevante para o estadiamento. Observar se o protocolo de pesquisa influenciou o número de linfonodos encontrados. Métodos: Cinquenta produtos de gastrectomia subtotal com linfadenectomia D2 por adenocarcinoma gástrico foram randomizados para fixação em Carnoy ou formalina com posterior dissecção da peça em busca de linfonodos. Após a dissecção do grupo Formalina, a gordura residual a ser desprezada foi imersa em Carnoy e reavaliada posteriormente. Os dados de 25 gastrectomias D2 operadas previamente ao estudo também foram avaliados. Resultados: A média de linfonodos encontrados nos grupos Carnoy e Formalina foi de 50,4 e 34,8; respectivamente (p < 0,001). Na gordura residual foram encontrados linfonodos em todos os casos (média 16,9 linfonodos), elevando a média do grupo Formalina para 51,7 (valor similar ao do grupo Carnoy, p=0,809). Com exceção de 1 linfonodo de 7mm, todos os demais encontrados na gordura residual mediram <= 3mm. Treze linfonodos metastáticos passaram despercebidos com a fixação em formalina e a revisão da gordura residual determinou a mudança de estadiamento de 2 (8%) pacientes. Os linfonodos encontrados no Carnoy possuíam tamanho significativamente menor quando comparados aos do grupo Formalina (p=0,01). A média de linfonodos encontrados no grupo retrospectivo foi similar ao do grupo Formalina prospectivo (p=0,802). Conclusões: Quando comparada à formalina, a solução de Carnoy permite encontrar número maior de linfonodos no espécime cirúrgico de gastrectomias com linfadenectomia. Linfonodos milimétricos foram perdidos após a fixação em formalina, estes foram identificados com o Carnoy e são clinicamente relevantes, pois podem conter metástases modificando assim, o estádio clínico e prognóstico do paciente. A implementação de protocolo de pesquisa não influenciou o número de linfonodos encontrados neste estudo / Background: Gastric adenocarcinoma is a frequent disease with high mortality ratio. Gastrectomy with lymphadenectomy is potentially curative, allows local control of the disease and provides material for TNM classification. While pathology examination of at least 16 lymph nodes is recommended following surgery, longer survival rates are expected when >=30 lymph nodes are examined, even for early gastric cancer. The understaging of patients with less examined lymph nodes justifies this findings. Small lymph nodes are particularly difficult to identify and fat clearing solutions have been proposed to improve this, but there is no evidence of their clinical benefit. Objectives: Compare Carnoy\'s solution (CS) and formalin in terms of the total number of examined lymph nodes following gastrectomy. Verify if surgically retrieved lymph nodes are lost with the formalin fixation and if this fact is clinically significant. Observe if a research protocol influences the number of examined lymph nodes. Methods: Fifty specimens of gastrectomy with D2 lymphadenectomy were randomized for fixation in CS or formalin with posterior dissection in search for lymph nodes. In the Formalin group, the residual fat to be discarded was immersed in CS and dissected again. Data from 25 D2 gastrectomies performed previously the present study were retrospectively analyzed. Results: The medium number of examined lymph nodes was 50.4 and 34.8 for CS and formalin, respectively (p < 0.001). Lost lymph nodes were found in all cases in the Residual Fat group (medium 16.9), this increased the Formalin group average to 51.7 (which is similar to the CS group, p=0.809). With one exception (7mm), all other examined lymph nodes in the Residual Fat group measured <= 3mm. Thirteen lymph nodes from this group were metastatic, this determined the upstaging of 2 (8%) patients. Lymph nodes from the CS group were smaller than those found in the formalin group (p=0.01). The medium number of retrieved lymph nodes in the retrospective group was similar to the formalin group (p=0.802). Conclusions: When compared to formalin, Carnoy\'s solution increases lymph node detection following gastrectomy with lymphadenectomy. CS identifies small lymph nodes lost with formalin fixation and that are clinically significant, since they may contain metastasis, modifying the TNM classification. No influence of the research protocol over the number of examined lymph nodes was observed in the present study.
98

Colorectal Cancer : Audit and Health Economy in Colorectal Cancer Surgery in a Defined Swedish Population

Jestin, Pia January 2005 (has links)
<p>Colorectal cancer is one of the most common malignancies in Sweden, with more than 5000 new cases annually. Median age at time of diagnosis is approximately 75 years. Owing to the ageing population, the incidence of colorectal cancer is increasing. The improvement in surgical technique and the introduction of adjuvant radio- and chemotherapy increased the 5-year survival rate from approximately 30-40% in the early 1960s to almost 60% in the late 1990s. The cost of public health care has risen considerably, and case-costing systems are increasingly demanded. Linked to clinical guidelines and quality registers, such control systems form a proper basis for quality assurance projects and improvement. The aim of this thesis is to describe the efficiency and cost effectiveness of colorectal cancer treatment in a defined Swedish population. Emergency surgery for colon cancer, constituting 25% of the cases, increased both mortality and cost. Among emergency cases there was not only an increase in postoperative mortality but also a stage specific decrease in long-term survival rate. Correct staging is decisive for further treatment of patients after colon cancer surgery and influences long-term survival. The number of lymph nodes examined varied between different pathology departments and could be used as a quality measurement. The proportion of tumour stage III increased the more nodes examined. A prognostic estimation of stage III cases that is less sensitive to the number of nodes examined is proposed. A case-control study aimed at identifying risk factors for anastomotic leakage after rectal cancer surgery confirmed previously known risk factors but failed to identify further steps during the perioperative course that were amenable to improvement. This research has confirmed that population-based quality and case-costing registers, linked to clinical guidelines, constitute a proper source for projects of quality improvement and decisions about distribution of resources in health care.</p>
99

Colorectal Cancer : Audit and Health Economy in Colorectal Cancer Surgery in a Defined Swedish Population

Jestin, Pia January 2005 (has links)
Colorectal cancer is one of the most common malignancies in Sweden, with more than 5000 new cases annually. Median age at time of diagnosis is approximately 75 years. Owing to the ageing population, the incidence of colorectal cancer is increasing. The improvement in surgical technique and the introduction of adjuvant radio- and chemotherapy increased the 5-year survival rate from approximately 30-40% in the early 1960s to almost 60% in the late 1990s. The cost of public health care has risen considerably, and case-costing systems are increasingly demanded. Linked to clinical guidelines and quality registers, such control systems form a proper basis for quality assurance projects and improvement. The aim of this thesis is to describe the efficiency and cost effectiveness of colorectal cancer treatment in a defined Swedish population. Emergency surgery for colon cancer, constituting 25% of the cases, increased both mortality and cost. Among emergency cases there was not only an increase in postoperative mortality but also a stage specific decrease in long-term survival rate. Correct staging is decisive for further treatment of patients after colon cancer surgery and influences long-term survival. The number of lymph nodes examined varied between different pathology departments and could be used as a quality measurement. The proportion of tumour stage III increased the more nodes examined. A prognostic estimation of stage III cases that is less sensitive to the number of nodes examined is proposed. A case-control study aimed at identifying risk factors for anastomotic leakage after rectal cancer surgery confirmed previously known risk factors but failed to identify further steps during the perioperative course that were amenable to improvement. This research has confirmed that population-based quality and case-costing registers, linked to clinical guidelines, constitute a proper source for projects of quality improvement and decisions about distribution of resources in health care.
100

Rôle de CD47 dans l’induction de la tolérance in vivo

Gautier-Éthier, Patrick 08 1900 (has links)
La tolérance orale permet la modulation de la réponse immunitaire à l’égard des antigènes exogènes présents dans la lumière intestinale. Essentiels à l’établissement d’une relation symbiotique entre le système immunitaire et la flore intestinale, l’induction et le maintien de la tolérance orale reposent sur différents mécanismes immunologiques. Parmi eux, l’induction de cellules T régulatrices par les cellules dendritiques et de mécanismes apoptotiques. Or, la glycoprotéine membranaire CD47 est impliquée, en périphérie, dans ces mécanismes. Cependant, le rôle de CD47 dans la tolérance orale n’est pas connu. À l’aide d’un modèle murin déficient en CD47, nous avons démontré principalement, que l’absence de CD47 est associée à une diminution de 50 % de la proportion de cellules dendrites myéloïdes CD11b+CD103- retrouvées dans les ganglions mésentériques. Suite au transfert adoptif de cellules T antigènes spécifiques dans nos différents modèles expérimentaux, on a, aussi, observé une diminution de 45 % de leur niveau d’activation dans les ganglions mésentériques. Malgré les effets observés, le CD47 n’est pas impliqué dans l’induction d’une réaction de tolérance orale secondaire à l’administration intragastrique de fortes doses d’ovalbumine. Cependant, nous avons démontré que CD47 est impliquée au niveau de la migration des cellules dendritiques de la peau et de certaines sous-populations retrouvées dans les ganglions mésentériques. / Oral tolerance allows the modulation of the immune response against exogenous antigens present in the intestinal lumen. Essential to establish a symbiotic relationship between the immune system and intestinal flora, the induction and maintenance of oral tolerance rests on different immunological mechanisms. Among them, induction of regulatory T cells by dendritic cells and apoptotic mechanisms. However, the membrane glycoprotein CD47 is involved in the periphery of these mechanisms. However, the role of CD47 in oral tolerance is unknown. With a mouse model deficient in CD47, we showed mainly that the absence of CD47 is associated with a decrease of 50% in the proportion of myeloid dendritic cells CD11b+ CD103- found in the mesenteric lymph nodes. Following the adoptive transfer of antigen specific T cells in our experimental models, we also observed a decrease of 45% of their level of activation in mesenteric lymph nodes. Despite the observed effects, CD47 is not involved in the induction of oral tolerance response secondary to intragastric administration of high doses of ovalbumin. However, we have shown that CD47 is involved in the migration of dendritic cells of the skin and some sub-populations found in mesenteric lymph nodes.

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