Objective: To determine the ameliorative effect of the ethanolic extract of Chuquiraga spinosa (ChS) on 7,12-Dimethylbenz[a]anthracene (DMBA)-induced breast cancer in rats. Methods: 36 female Holztman rats were divided into 6 groups. I) The negative control group received physiological saline (PS). II) ChS-200 group received 200 mg/kg of ChS. III) DMBA group was induced with DMBA (20 mg/Kg) dissolved in PS and administrated orally for 15 weeks. IV) DMBA + ChS-50 group, V) DMBA + ChS-250 group, and VI) DMBA + ChS-500 group, which received the extract orally for 15 weeks after DMBA induction. All data were expressed as mean and standard deviation. One-way analysis of variance (ANOVA) followed by Dunnet test was carried out to compare the mean value of different groups Histopathological analysis was evaluated by using Image J software. Results: Hematology showed that the triglyceride level was significantly lowered (P< 0.01) and high-density lipoprotein (HDL) level was significantly increased (P <0.01) in groups III, IV and V. Also, ChS extract significantly lowered the C reactive protein (CRP) level (P <0.01) and malondialdehyde level (P<0.05). There was a significant decrease in the frequency of DMBA-induced micronucleated polychromatic erythrocyte (P<0.01). Conclusions: Chuquiraga spinosa showed an ameliorative effect on DMBA-induced breast cancer in rats as well as antioxidant, antitumor and antigenotoxic properties. / Revisión por pares

Les lymphocytes T régulateurs (Treg) jouent un rôle prépondérant dans la tolérance du système immunitaire. En physiopathologie, un défaut quantitatif ou fonctionnel en Treg favorise le développement de maladies auto-immunes tandis que leur présence participe au développement tumoral. En particulier, la présence de Treg dans le stroma immunitaire de la tumeur (TiTreg) est de mauvais pronostic pour la survie des patientes atteintes de cancers du sein et de l'ovaire. Les Treg sont recrutés dans la tumeur via l'axe CCL22/CCR4 et sont activés et amplifiés via leur interaction avec les pDC et l'axe de co-stimulation ICOS-ICOSL qui favorise leurs capacités suppressives. Ce projet contribue aux efforts réalisés ces dernières années visant à la compréhension des mécanismes d'immunosuppression des Treg opérant dans les tumeurs humaines. En effet, ce projet met en évidence que les Ti-Treg humains expriment fortement l'ectonucléotidase membranaire CD39. Cette enzyme extracellulaire catabolise l'Adénosine tri-phosphate (ATP) en Adénosine Monophosphate (AMP) pouvant être ensuite dégradé, via l'ectonucléotidase CD73, en Adénosine (Ado). Alors que l'ATP représente une Alarmine (signal de danger extracellulaire) qui en particulier contribue à l'activation de l'inflammasome, l'Ado possède un fort pouvoir immunosuppresseur qui est illustré chez les patients atteints d'une déficience de l'enzyme Adénosine Déaminase (ADA), ne pouvant dégrader l'Ado en Inosine (Ino), développent un Syndrome d'Immunodéficience Sévère. Contrairement au Treg murins, les Treg humains n'expriment pas CD73. Cependant nous avons pu identifier une population de lymphocytes T CD4+ mémoires non régulateurs (Tconv) exprimant CD73 et coopérant ainsi avec les Treg CD39+ pour la génération d'Ado. Cette population présente une capacité accrue de sécrétion de cytokines inflammatoires (IFNgamma, IL-17A, IL-22, GM-CSF) et l'expression de molécules (CXCR3, CCR6, MDR1) caractéristiques du profil Th1/17. De plus ces cellules semblent être moins sensibles à une régulation médiée par les points de contrôles dits immune-checkpoints (ICPs) tel que PD-1, CTLA-4, TIM-3, TIGIT. Par contre, les Tconv CD73+ sont sensibles à l'Ado généré lors de la coopération avec les Treg CD39+ qui engendre l'inhibition de leur prolifération et de leur sécrétion d'IFNgamma et de GM-CSF mais pas de l'IL-17A. L'Ado qui agit localement, peut également entrainer la suppression des Tconv CD73neg dans l'environnement proche. L'ensemble de ces résultats montre que l'expression de CD73 caractérise une population de T CD4 effecteurs polyfonctionnelle Th1/17 qui est une cible privilégiée et coopérative de l'immunosuppression des Treg dans l'environnement tumoral. En outre l'action d'Ado transforme ce puissant effecteur anti-tumoral en cellule potentiellement pro-tumorale via l'unique sécrétion privilégiée d'IL17 / Regulatory T cells (Tregs) play a key role in the immune system tolerance. In pathophysiology, a quantitative or functional defect in Treg promotes development of autoimmune diseases while their presence involved in tumor development. In particular, the presence of Treg in the immune stromal tumor environment (Ti-Treg) is associated with a poor prognosis for survival of patients suffering from breast cancer and ovarian cancer. Treg are recruited in the tumor through the CCL22 / CCR4 axis and are activated and amplified through their interaction with pDC expressing costimulatory axis ICOS-ICOSL and promoting their suppressive capacity. This project contributes to the efforts made in recent years to understand suppressive mechanisms of Treg operating in human tumors. Indeed, this project demonstrates that humans Ti-Treg strongly express the membrane ectonucleotidase CD39. This extracellular enzyme catabolizes Adenosine-triphosphate (ATP) to adenosine-monophosphate (AMP) which can then be degraded through the ectonucleotidase CD73 into Adenosine (Ado). While ATP is an Alarmine (extracellular danger signal) that particularly contributes to the inflammasome activation, Ado has strong immunosuppressive effect which is illustrated in patients with deficiency of the enzyme Adenosine Deaminase (ADA), which cannot degrade Ado into Inosine (Ino) and develop an Immunodeficiency Syndrome Severe. Unlike murine Treg, human Treg do not express CD73. However we could identify a non-regulatory population of CD4+ T cells (Tconv) expressing CD73, and thus cooperating with CD39+ Treg for Ado generation. This population has an increased capacity of secretion of inflammatory cytokines (IFNgamma, IL-17A, IL-22, GM-CSF) and the expression of molecules (CXCR3, CCR6, MDR1) characteristics of Th1/17 profile. Moreover, these cells appear to be less sensitive to regulation mediated by the immunocheckpoints (ICPs), such as PD-1, CTLA-4, TIM-3, TIGIT. Nonetheless CD73+ Tconv are sensitive to Ado generated in cooperation with CD39+ Treg which induce the inhibition of their proliferation and their secretion of IFNgamma and GM-CSF but not IL-17A . Ado acting locally, can also inhibit the Tconv CD73neg in the surrounding environment. All these results show that the expression of CD73 characterizes a population of multifunctional effector T CD4 Th1/17, which is a specific and cooperative target of Treg immunosuppression in the tumor environment. In addition the action of Ado transforms this potent anti-tumor effector to potentially pro-tumor cells which only secret IL17

Orientador: Ary Fernandes Junior / Resumo: Espécies vegetais são fontes de moléculas biologicamente ativas que têm um importante papel no desenvolvimento de novos fármacos e, portanto, suas propriedades merecem ser investigadas. Apesar de serem espécies aromáticas e apresentarem um potencial farmacológico, algumas atividades biológicas dos óleos essenciais das folhas de Protium heptaphyllum, Hedyosmum brasiliense, Blepharocalyx salicifolius, Baccharis dracunculifolia e Nectandra megapotamica ainda não foram avaliadas. O objetivo deste trabalho foi verificar a ação citotóxica, antileishmania e antimicrobiana destes óleos essenciais com o intuito de estabelecer espécies vegetais com potencial uso na elaboração de fármacos ou como terapias complementares aos tratamentos convencionais de doenças de impacto em saúde pública. Os óleos essenciais foram obtidos por destilação de folhas frescas por arraste de vapor, a composição química determinada por análises de cromatografia gasosa/espectrometria de massas, as atividades biológicas testadas utilizando o método de microdiluição e a verificação dos mecanismos de morte celular feita por citometria de fluxo. B. salicifolius e B. dracunculifolia apresentaram elevado rendimento (0,86% e 0,89% respectivamente) quando comparado aos demais óleos essenciais avaliados. H. brasiliense e B. salicifolius apresentaram resultados promissores sobre linhagens tumorais Ehrlich (51,59 e 42,04 μg mL-1) e MDA-MB-231 (62,40 e 46,60 μg mL-1), com maior ação seletiva para estes tipos celulares se c... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: lant species are sources of biologically active molecules that play an important role in the development of new drugs, and therefore, their properties deserve to be investigated. In this regard, Protium heptaphyllum, Hedyosmum brasiliense, Blepharocalyx salicifolius, Baccharis dracunculifolia and Nectandra megapotamica are aromatic species with pharmacological potential, producing essential oils whose biological activities had not yet been investigated. The aim of this work was to assess any cytotoxic, antileishmania, or antimicrobial action of these essential oils to determine those plant species with potential in the elaboration of drugs or in complementary treatments of diseases with an impact on public health. Essential oils were obtained from fresh leaves by steam distillation. Chemical composition was determined by gas chromatography/mass spectrometry. Biological activities were assessed using the microdilution method while cell death was checked by flow cytometry. B. salicifolius and B. dracunculifolia presented high yields (0.86% and 0.89%, respectively) relative to the other species assessed. H. brasiliense and B. salicifolius showed promising action on Ehrlich (at 51.59 and 42.04 μg mL-1 concentration respectively) and MDA-MB-231 tumor lines (at 62.40 and 46.60 μg mL-1 concentration respectively), with less selective action against normal MCF-10A breast cells (at > 512 and 314.44 μg mL-1 concentration respectively). Flow cytometry results showed that B. salicifolius... (Complete abstract click electronic access below) / Doutor

Since aggressive cancers are frequently hypermetabolic with angiogenic vessels, quantification of blood flow (BF) can be vital for cancer diagnosis. Our laboratory has developed a noncontact diffuse correlation tomography (ncDCT) system for 3-D imaging of BF distribution in deep tissues (up to centimeters). The ncDCT system employs two sets of optical lenses to project source and detector fibers respectively onto the tissue surface, and applies finite element framework to model light transportation in complex tissue geometries. This thesis reports our first step to adapt the ncDCT system for 3-D imaging of BF contrasts in human breast tumors. A commercial 3-D camera was used to obtain breast surface geometry which was then converted to a solid volume mesh. An ncDCT probe scanned over a region of interest on the breast mesh surface and the measured boundary data were used for 3-D image reconstruction of BF distribution. This technique was tested with computer simulations and in 28 patients with breast tumors. Results from computer simulations suggest that relatively high accuracy can be achieved when the entire tumor was within the sensitive region of diffuse light. Image reconstruction with a priori knowledge of the tumor volume and location can significantly improve the accuracy in recovery of tumor BF contrasts. In vivo ncDCT imaging results from the majority of breast tumors showed higher BF contrasts in the tumor regions compared to the surrounding tissues. Reconstructed tumor depths and dimensions matched ultrasound imaging results when the tumors were within the sensitive region of light propagation. The results demonstrate that ncDCT system has the potential to image BF distributions in soft and vulnerable tissues without distorting tissue hemodynamics. In addition to this primary study, detector fibers with different modes (i.e., single-mode, few-mode, multimode) for photon collection were experimentally explored to improve the signal-to-noise ratio of diffuse correlation spectroscopy flow-oximeter measurements.

Les cellules dendritiques {DC) jouent un rôle majeur dans l'induction de l'immunité anti-tumorale spécifique de l'antigène {Ag). Récemment, les DC BDCA3high humaines sont apparues comme étant homologues aux DC CD8a+ connues pour activer très efficacement les lymphocytes T CD8 par présentation croisée d'Ag chez la souris. Par ailleurs, ces deux populations de DC sont les productrices principales d'interféron-λ{IFN-λ), une cytokine récemment découverte et possédant des propriétés antivirales, antiprolifératives et anti-tumorales. Mon travail de thèse a permis de mieux caractériser la présentation croisée d'Ag cellulaire par les DC BDCA3high à l'aide d'un modèle in vitro et de mettre en lumière le rôle des cellules NK dans l'induction de ce processus. Ce travail a également aboutit à la mise en évidence des DC BDCA3high dans les tumeurs de sein et de révéler l'inhibition de leur sécrétion d'IFN-λ par des facteurs solubles présents dans le microenvironnement tumoral. L'ensemble de ces résultats devraient permettre de concevoir de nouvelles stratégies thérapeutiques basées sur le ciblage des DC BDCA3high / Dendritic cells {DC) play a major role in the induction of antigen {Ag) specific anti-tumoral immunity. Recently, human BDCA3high DC appeared to be homologous with CD8a+ DC known to activate very efficiently T CD8 lymphocyte by Ag cross-presentation in mice. Moreover, those two DC populations are the main producers of interferon-λ {IFN-λ), a recently discovered cytokine family with antiviral, anti-proliferative and anti-tumoral properties. My works participated to better characterize cell derived Ag cross-presentation by BDCA3high DC using an in vitro model and enlightened the role of NK cells in its induction. This works also end up in revealing the presence of BDCA3high DC in breast tumors and the inhibition of their IFN-λsecretion by soluble factor from tumor microenvironment. Altogether, those results should allow designing new anti-tumoral immunotherapeutic strategies based on BDCA3high DC targeting

Many medical devices have been shifting to personal platforms such as smartphones due to its ubiquitous availability, variety of included sensors, robust communication, and user-friendliness. By utilizing smartphones as a medical sensing device should improve the early detection of abnormalities and the long-term monitoring of health conditions. Tissue abnormalities will be detected by touch sensation due to mechanical property changes within the tissue. However, touch sensation is unquantifiable and subjective. We integrate the smartphone with a tactile sensor to build a portable and personalized tissue assessment device based on changes in mechanical properties. The Smartphone Tactile Imaging Probe (STIP) is developed to quantify the mechanical properties of the tissue. The proposed system has a dual-sensing mode: compression-based sensing (STIP-C) and indentation-based sensing (STIP-I). STIP–C is designed to detect and measure the size and hardness of the inclusion. It assesses mechanical property changes caused by the tumor inside the tissue. STIP–I is designed to measure the pitting parameters and viscoelastic properties of the tissue. This system will assess the viscoelasticity changes caused by fluid retention within the tissue. STIP estimates mechanical and viscoelastic behavior changes in the tissue and provides the risk evaluation of an underlying health problem. Breast cancer risk assessment and edema severity level classification are the main applications of STIP. We estimate the breast cancer risk by incorporating the patient’s personal risk value into the STIP-C data associated with the tumor mechanical properties to improve the risk assessment accuracy. To classify the edema severity level, the STIP-I measures the pitting parameters and viscoelastic properties of the tissue. From these parameters, we build a Viscoelastic Pitting Recovery (VPR) model. The model illustrates the changes in tissue viscoelastic behavior associated with the edema severity level. Using the VPR model, we use the thresholding method to classify the edema cases. We also developed customized phantoms representing the different amounts of fluid retention in the tissue. The experimental result found a relationship between the amounts of pitted depth from STIP-I and the fluid amount of a phantom. In this dissertation, we developed and tested a portable tissue mechanical property estimation system. The interchangeable dual-mode STIP sensing probe and risk assessment methods were developed for the breast tumor malignancy and edema severity applications. / Electrical and Computer Engineering

This dissertation presents a contribution to quantitative microwave imaging for breast tumor detection. The study made in the frame of a joint supervision Ph.D. thesis between University Paris-SUD 11 (France) and Mälardalen University (Sweden), has been conducted through two experimental microwave imaging setups, the existing 2.45 GHz planar camera (France) and the multi-frequency flexible robotic system, (Sweden), under development. In this context a 2D scalar flexible numerical tool based on a Newton-Kantorovich (NK) scheme, has been developed. Quantitative microwave imaging is a three dimensional vectorial nonlinear inverse scattering problem, where the complex permittivity of an object is reconstructed from the measured scattered field, produced by the object. The NK scheme is used in order to deal with the nonlinearity and the ill-posed nature of this problem. A TM polarization and a two dimensional medium configuration have been considered in order to avoid its vectorial aspect. The solution is found iteratively by minimizing the square norm of the error with respect to the scattered field data. Consequently, the convergence of such iterative process requires, at least two conditions. First, an efficient calibration of the experimental system has to be associated to the minimization of model errors. Second, the mean square difference of the scattered field introduced by the presence of the tumor has to be large enough, according to the sensitivity of the imaging system. The existing planar camera associated to a flexible 2D scalar NK code, are considered as an experimental platform for quantitative breast imaging. A preliminary numerical study shows that the multi-view planar system is quite efficient for realistic breast tumor phantoms, according to its characteristics (frequency, planar geometry and water as a coupling medium), as long as realistic noisy data are considered. Furthermore, a multi-incidence planar system, more appropriate in term of antenna-array arrangement, is proposed and its concept is numerically validated. On the other hand, an experimental work which includes a new fluid-mixture for the realization of a narrow band cylindrical breast phantom, a deep investigation in the calibration process and model error minimization, is presented. This conducts to the first quantitative reconstruction of a realistic breast phantom by using multi-view data from the planar camera. Next, both the qualitative and quantitative reconstruction of 3D inclusions into the cylindrical breast phantom, by using data from all the retina, are shown and discussed. Finally, the extended work towards the flexible robotic system is presented. / A dissertation prepared through an international convention for a joint supervision thesis with Université Paris-SUD 11, France / Microwaves in biomedicine

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