La question du bien-être des animaux d’élevage et plus particulièrement celle de la douleur fait l’objet d’une attente sociétale grandissante. Cependant, l’évaluation de la douleur chez l’animal, et par voie de conséquence de l’efficacité des traitements antalgiques, reste très complexe en médecine vétérinaire, en expérimentation ou en élevage. Elle s’appuie principalement sur les modifications de comportement ou de paramètres physiologiques du système nerveux autonome, de l’axe hypothalamo-hypophysaire ou encore des processus inflammatoires. Néanmoins, les indicateurs généralement utilisés ne sont pas tous spécifiques de la douleur "ressentie" par l'animal mais peuvent également indiquer un niveau de stress ou de perturbations physiologiques et métaboliques liés au traumatisme. Chez les carnivores domestiques ou les chevaux, une approche combinant des indicateurs spécifiques de chacune des voies sollicitées dans les processus douloureux a été développée. Aucune démarche équivalente n'a été validée chez les animaux de rente. Cette thèse conduite sur ovin et bovin avait pour objectifs : 1) de développer une approche multiparamétrique d'évaluation de la douleur, ou de situations potentiellement douloureuses, 2) de tester ses performances dans différentes situations considérées douloureuses (douleurs somatiques et/ou viscérale : mammites, castration et pose de canules digestives), et 3) sur la base de cette approche d’évaluer l'efficacité de protocoles antalgiques utilisés en élevage ou en expérimentation animale. Nous montrons que (i) l’approche multiparamétrique est plus performante qu’une approche voie par voie, (ii) les modifications du comportement, de l’axe hypothalamo-hypophysaire et de l’inflammation discriminent des situations potentiellement douloureuses quel que soit le type de douleur alors que les modifications liées au stress oxydant sont davantage liées aux situations présentant des douleurs d'origine viscérale et somatique, (iii) l’approche multiparamétrique différencie les périodes les plus critiques à prendre en charge en fonction de la douleur ressentie et (iv) il est possible de proposer des ajustements des traitements antalgiques en utilisant les renseignements fournis par chacune des voies évaluées. En prenant en compte l'ensemble des principales voies impliquées dans les processus douloureux, l’évaluation de la douleur ressentie, peut donc être plus sensible et spécifique. Néanmoins, l’approche multiparamétrique gagnera à être simplifiée et devra être validée dans d'autres situations douloureuses, notamment dans le cas de douleurs neuropathique, avant d'être proposée sur le terrain aux vétérinaires, éleveurs ou expérimentateurs. / There is a growing societal concern regarding farm animal welfare and especially pain assessment. However, pain assessment in animals and the efficiency of analgesic treatments remains very complex in veterinary medicine, animal experimentation or farming. Pain assessment is mainly based on behavioural changes or physiological responses related to the autonomic nervous system, hypothalamic-pituitary axis or inflammatory processes. Nevertheless, the indicators usually used do not always reflect pain experienced by animals but can also reflect the level of stress or physiological and metabolic disturbances related to trauma. Combinations of pathway-specific indicators involved in pain have been developed in various animal species (carnivore pets and horses), but no equivalent approach has been validated for farm ruminants yet. The main objectives of this thesis were 1) to develop a multiparametric approach to assess pain in sheep and cattle, 2) to test its performances in different painful situations (somatic and/or visceral pain: mastitis, castration and digestive cannulas), and 3) to assess the efficiency of analgesic treatments currently used in farming or research. We showed that (i) the multiparametric approach is more efficient than a single pathway approach (ii) changes in behaviour, hypothalamic-pituitary axis, and inflammation discriminate potentially painful situations regardless of the type of pain, whereas changes related to oxidative stress are related to visceral and somatic painful situations, (iii) the multiparametric approach differentiates the most critical periods requiring specific pain management (to be managed according to the pain), and (iv) it is possible to adjust the analgesic treatments according to the information provided by the assessment of each pathway. In conclusion, taking into account the main pathways involved in painful processes, allows a more sensitive and specific pain evaluation. Further research should aim at simplifying the multiparametric approach and validating it against other painful situation (especially neurological pain) before proposing it for practical-use on field by veterinarians, farmers and researchers.

Chez les ruminants, l’Acidose Ruminale SubAiguë (ARSA) est une maladie d’origine nutritionnelle qui fait suite à une perturbation des fermentations microbiennes et à une acidité anormale du compartiment ruminal. L’installation chronique de ce dysfonctionnement digestif peut avoir une incidence néfaste sur l’efficacité de production et la santé des animaux. À l’échelle de l’individu ou du troupeau, elle aura pour conséquences des retombées économiques négatives pour l’éleveur. Un des problèmes majeurs de cette maladie est qu’elle ne se manifeste pas par des signes cliniques spécifiques. A l’heure actuelle, seul le pH ruminal permet d’objectiver la maladie même si aucun indicateur de pH ne fait l’unanimité, notamment du fait des variabilités importantes liées à la technique de mesure du pH d’une part et à la susceptibilité des animaux d’autre part. Dans ce contexte, cette thèse a eu pour objectif d’améliorer le diagnostic individuel de l’ARSA chez la vache laitière en développant une approche multiparamétrique applicable sur le terrain. Nous proposons de nouveaux indicateurs issus de cinétiques de pH mesuré de façon non-invasive avec des bolus intra-ruminaux. Ces nouveaux indicateurs relatifs, calculés quotidiennement sur les cinétiques normalisées sur 0 (NpH), sont le temps passé sous NpH <-0,3, l’écart type et l’amplitude. Ils permettent de pallier les fortes sources de variabilité et présentent l’intérêt d’être transposables entre études et sont plus précis pour caractériser l’ARSA. Parallèlement, nous avons développé des modèles multiparamétriques composés de plusieurs paramètres mesurés simultanément dans différents compartiments biologiques (lait, fèces, salive, sang, urine) ou sur l’animal (comportement). Leur capacité de prédiction de l’ARSA a ensuite été évaluée en élevage. Certains modèles incluant des paramètres périphériques au rumen et simples à mesurer sur le terrain présentent une bonne sensibilité (concentration en urée dans le lait, en bicarbonate dans le sang, pH salivaire), et d’autres ont une bonne spécificité (nombre de buvées de l’animal, pH fécal, concentration en urée dans le lait). Néanmoins, aucun modèle ne renferme un couple sensibilité et spécificité satisfaisant. A l’issue de ce travail nous proposons une stratégie diagnostique fondée sur 4 étapes : 1) l’analyse du contexte de diagnostic de l’ARSA, 2) l’évaluation des facteurs de risques, 3) l’évaluation des modèles multiparamétriques et 4) le calcul d’indicateurs NpH ruminaux des individus à risque. / In ruminants, subacute ruminal acidosis (SARA) is a nutritional disease that induces an abnormal acidity of the rumen compartment as well as disturbance in microbial fermentation. When the disease becomes chronic, it can lead to negative effects on production efficiency and animal health at the individual or the herd scales, with negative economic consequences for the farmer. One of the major problems of SARA is that there are no obvious clinical signs. Presently, the only benchmark to define SARA is rumen pH. However, no pH indicator is unanimous due to the important variability related both to the measurement technique itself and to the animal susceptibility. In this context, this thesis aimed to improve the individual diagnosis of SARA in dairy cows by developing a multiparametric approach that could be used on field. We propose new indicators of pH kinetics measured noninvasively with intra-ruminal boluses. These new relative indicators, calculated daily (kinetic normalised on 0, NpH), consist of the time spent under NpH < - 0.3, the NpH standard deviation and the NpH range. These indicators make it possible to overcome the strong sources of variability and have the advantage of being transposable while being more accurate to characterize SARA. At the same time, we have developed multiparametric models including a number of parameters measured simultaneously in various biological compartments (milk, faeces, saliva, blood, urine) or on animal behaviour. The models ability to predict SARA has been evaluated on field. Some models including rumen peripheral parameters (concentration of urea in milk, of bicarbonate in blood, salivary pH) have a proficient sensitivity while others have a proficient specificity (number of drinking acts, faecal pH, and urea concentration in milk). However, no model developed is both sensitive and specific enough. The diagnostic strategy we propose is based on 4 steps: 1) analysis of the SARA diagnostic context, 2) assessment of risk factors, 3) evaluation of multiparametric models and (4) determination of ruminal NpH indicators for individuals presenting a high risk of SARA.

Submitted by (edna.saturno@ufrpe.br) on 2016-10-06T15:19:52Z No. of bitstreams: 1 Fabiani Coutinho Lordao Rodrigues.pdf: 269999 bytes, checksum: 3b5c809f839498d25c45327042b6e816 (MD5) / Made available in DSpace on 2016-10-06T15:19:52Z (GMT). No. of bitstreams: 1 Fabiani Coutinho Lordao Rodrigues.pdf: 269999 bytes, checksum: 3b5c809f839498d25c45327042b6e816 (MD5) Previous issue date: 2006-06-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / To assist in the birth control rate or to avoid the appearance of reproductive pathologies, several contraceptive methods have been used in canine females. In this context, the ovarysalpingohysterectomy (OSH) is the method of larger demand for sterilization of female dogs, however this method is still associated to several undesirable effects. Therefore this paper constituted of two experiments that was developed with the objective of evaluating the influence of the estral cycle phase on the physiologic parameters of female dogs submitted to elective OSH on the pre and trans-operative periods. In experiment 1 was determined the phase of the estral cycle through vaginal cytology in female dogs (n=31) submitted to clinical evaluation of the physiologic parameters: heart rate (HR), respiratory frequency (RF) and rectal temperature (RT), in the preoperative period. All females were also submitted to clinical gynecological exam. The animals were separate in four experimental groups G1 (n=14), G2 (n=5), G3 (n=5) and G4 (n=7), corresponding to the animals in proestro, estro, diestro and anestro phase, respectively. The averages of HR varied from 116,8 to 124; of RF from 39,2 to 42 and RT from 38,7 to 38,99ºC, not proving significant difference (p≥0,05) among the analyzed groups. Therefore, it can be concluded that the phase of the estral cycle does not influence on the parameters HR, RF and RT on female dogs in the immediate pre-operative period. In experiment 2 were evaluated the parameters heart rate (HR), respiratory frequency (RF), rectal temperature (RT), arterial pulse (P) and oxygen saturation (SpO2) in female dogs (n=31) according to the estral cycle phase, during the accomplishment of elective OVH. The animals were distributed in four experimental groups: G1 (n=14), G2 (n=5), G3 (n=5) and G4 (n=7), corresponding to the animals in proestro, estro, diestro and anestro phase, respectively. The measurements were made with a multiparametric monitor in intervals of 5 minutes until the end of the surgical procedure. As far as the results, the HR in G3 was superior (p≥0,05) to the groups G2 and G4 only in the first five minutes (T1). The RF did not differ in any of the times evaluated, RT whose averages varied from 36,5 to 37,7ºC, also did not demonstrate difference among the analyzed groups, as well as the evaluations of the SpO2. The results obtained allows to conclude that the monitored parameters, did not suffer alterations in relation to the phases of the estral cycle, during the intra-operative period, with the anesthetic protocol used. Due the studied conditions, it can be conclude that the evaluated parameters in the immediate pre-operative period and trans-operative, did not suffer influence of the estral cycle phases in female dogs. / Para auxiliar no controle da natalidade ou evitar o surgimento de patologias da esfera reprodutiva diversos métodos contraceptivos vêm sendo utilizados em fêmeas caninas. Neste contexto, a ováriosalpingohisterectomia (OSH) é o método de maior demanda para esterilização de cadelas, entretanto este método ainda é associado a diversos efeitos indesejáveis. Assim sendo, este trabalho constituído de dois experimentos foi conduzido com o objetivo de avaliar a influência da fase do ciclo estral sobre os parâmetros fisiológicos nos períodos pré e trans-operatório em cadelas submetidas a OSH eletiva. No experimento 1 determinou-se a fase do ciclo estral através de citologia vaginal em cadelas (n=31) submetidas à avaliação clínica dos parâmetros fisiológicos: freqüência cardíaca (FC), freqüência respiratória (FR) e temperatura retal (TR), no período pré-operatório imediato. Todas as fêmeas foram também submetidas a exame clínico-ginecológico. Os animais foram separados em quatro grupos experimentais G1 (n=14), G2 (n=5), G3 (n=5) e G4 (n=7), correspondente aos animais em proestro, estro, diestro e anestro respectivamente. As médias da FC variaram de 116,8 a 124, da FR de 39,2 a 42 e da TR da 38,7 a 38,99ºC, não se comprovando diferença significativa (p≥0,05) entre os grupos analisados. Portanto, pode-se concluir que a fase do ciclo estral não exerce influência sobre os parâmetros FC, FR e TR em cadelas no período pré-operatório imediato. No experimento 2 avaliou-se os parâmetros freqüência cardíaca (FC), freqüência respiratória (FR), temperatura retal (TR), pulso arterial (P) e saturação do oxigênio (SpO2) em cadelas (n=31) de acordo com a fase do ciclo estral, durante a realização de OSH eletiva. Os animais foram distribuídos em quatro grupos experimentais: G1 (n=14), G2 (n=5), G3 (n=5) e G4 (n=7), correspondente aos animais em proestro, estro, diestro e anestro respectivamente. As medições foram feitas com o auxílio de um monitor multiparamétrico em intervalos de 5 minutos até o término do procedimento cirúrgico. Quanto aos resultados a FC no G3 foi superior (p≥0,05) aos grupos G2 e G4 apenas nos primeiros cinco minutos (T1). A FR não diferiu em nenhum dos tempos avaliados, a TR cujas médias variaram de 36,5 a 37,7ºC, também não demonstrou diferença entre os grupos analisados, bem como para as avaliações do P e da SpO2. Os dados obtidos permitem concluir que os parâmetros monitorados, não sofrem alterações diante das fases do ciclo estral, durante o período intra-operatório, com o protocolo anestésico utilizado. Diante das condições estudadas, pode-se concluir que os parâmetros avaliados nos períodos pré-operatório imediato e trans-opratório, não sofrem influência das fases do ciclo estral em cadelas.

The aim of the thesis was familiarity of segmentation methods for automatic segmentation of MR images, using multiparametrical display. The theoretical part focuses on the description of methods of segmentation techniques. In the practical part are implemented K-means and level-set method. The methods are tested on the images of the brain obtained by different sequences (T1, T1c, T2, FLAIR). Segmentation methods are implemented in the program MATLAB. Implemented segmentation accuracy is demonstrated on data which there are reports reference results. Evaluation methods is performed using different classifiers decision. The K-means method is tested different metrics and different combinations of the input image. Finally, both methods are compared with one another and visually evaluated against the reference image.

This diploma thesis deals with the possibilities of multiparametric fluorescence spectroscopy, since the main objective of this experiment was to evaluate the possibilities of multiparametric measurements in the fluorescence spectroscopy laboratory. A suitable fluorescence probe was proposed for this type of experiment that shows high sensitivity for pH changes in the environment, SNARF-4F AM, based on a literature research. The fluorophore was dissolved in solutions of different pH and this system was examined using a time-resolved spectrofluorimeter. The method named TRES (time-resolved emission spectra) was used to obtain the emission spectra of the probe and to find the emission maximum. Fluorescence intensity decay measurements as a function of wavelengths allowed to create deconvolution of the emission spectra, which provided information about the fluorescent lifetime and the relative representation of the states of probes in the solution. Later, the probe was dissolved in solutions of different density and pH - this system served for anisotropic measurements, during which the individual correlation-rotational times of the fluorophore were obtained. The obtained results were then used as the basis for multiparametric analysis, which was performed by using a fluorescence correlation microscope and a spectrograph. This combination allows to measure the necessary fluorescence parameters in one step. A standard operating procedure was created for the spectrograph’s control. On the basis of the obtained information the suitability, accuracy and sensitivity of the multiparametric analysis were qualified.

Ph. D. Thesis / In order to compute more realistic production plans and schedules, techniques using nonlinear programming (NLP) and mixed-integer nonlinear programming (MINLP) have gathered a lot of attention from the industry and academy. Efficient solution of these problems to a proven ε-global optimality remains a challenge due to their combinatorial, nonconvex, and large dimensionality attributes. The key contributions of this work are: 1) the generalization of the inventory pinch decomposition method to scheduling problems, and 2) the development of a deterministic global optimization method. An inventory pinch is a point at which the cumulative total demand touches its corresponding concave envelope. The inventory pinch points delineate time intervals where a single fixed set of operating conditions is most likely to be feasible and close to the optimum. The inventory pinch method decomposes the original problem in three different levels. The first one deals with the nonlinearities, while subsequent levels involve only linear terms by fixing part of the solution from previous levels. In this heuristic method, infeasibilities (detected via positive value of slack variables) are eliminated by adding at the first level new period boundaries at the point in time where infeasibilities are detected. The global optimization algorithm presented in this work utilizes both piecewise McCormick (PMCR) and Normalized Multiparametric Disaggregation (NMDT), and employs a dynamic partitioning strategy to refine the estimates of the global optimum. Another key element is the parallelized bound tightening procedure. Case studies include gasoline blend planning and scheduling, and refinery planning. Both inventory pinch method and the global optimization algorithm show promising results and their performance is either better or on par with other published techniques and commercial solvers, as exhibited in a number of test cases solved during the course of this work. / Thesis / Doctor of Philosophy (PhD) / Optimal planning and scheduling of production systems are two very important tasks in industrial practice. Their objective is to ensure optimal utilization of raw materials and equipment to reduce production costs. In order to compute realistic production plans and schedules, it is often necessary to replace simplified linear models with nonlinear ones including discrete decisions (e.g., “yes/no”, “on/off”). To compute a global optimal solution for this type of problems in reasonable time is a challenge due to their intrinsic nonlinear and combinatorial nature. The main goal of this thesis is the development of efficient algorithms to solve large-scale planning and scheduling problems. The key contributions of this work are the development of: i) a heuristic technique to compute near-optimal solutions rapidly, and ii) a deterministic global optimization algorithm. Both approaches showed results and performances better or equal to those obtained by commercial software and previously published methods.

La dystrophie musculaire de Duchenne (DMD) est la maladie neuromusculaire la plus fréquente de l'enfant. Son évolution progressive inexorable conduit habituellement au décès dans la troisième décade. La DMD constitue cependant une affection hétérogène pour la sévérité de l'atteinte musculaire, cognitive et cardiaque, et cette hétérogénéité n'est pas totalement expliquée par la localisation des mutations dans le gène de la dystrophine. Ma thèse comporte trois volets: (1) une analyse clinique multivariée d'une cohorte de DMD suivie à long terme qui nous a permis de définir 4 phénotypes distincts de DMD; (2) une étude de corrélation clinico-pathologique qui a identifié la fibrose endomysiale précoce comme seul facteur histologique prédictif de sévérité motrice; (3) la mise au point d'un modèle murin original de myofibrose dystrophique chez la souris mdx déficiente en dystrophine. 1- Étude multiparamétrique clinique. La saisie par la même équipe des données fonctionnelles musculaires, cardiaques, respiratoires et cognitives de 75 patients atteints de DMD (tous génotypés et présentant une absence complète de dystrophine musculaire), suivis pendant &gt;10 ans, a permis d'établir un modèle multiparamétrique satisfaisant à deux dimensions principales, cognitive et motrice, et de définir 4 clusters phénotypiques : (i) DMD cognitive et motrice congénitale (20%), (ii) DMD classique (28%), (iii) DMD motrice pure modérée (22%), (iv) DMD motrice pure sévère (30%). La corrélation génotypephénotype était restreinte à la seule atteinte cognitive. Des indicateurs pronostics précoce ont été identifiés et validés sur une 2ème série de 34 patients. 2- Étude histopathologique. Les variations de sévérité de l'atteinte musculaire n'étant pas expliquées par la génétique moléculaire, nous avons cherché à corréler les paramètres moteurs et la biopsie musculaire prélevée dans le quadriceps à un stade précoce (3-7 ans) chez 25 patients (analyse stéréologique des images numérisées pour les paramètres élémentaires: nécrose/régénération, fibres hypercontractées, adipocytes, fibrose endomysiale et périmysiale). Seule la fibrose endomysiale était associée à un pronostic moteur défavorable (p&lt;0.002) attesté par l'âge de perte de marche, la force du quadriceps et le testing musculaire global à 10 ans. Cette fibrose endomysiale dissociait les capillaires des myofibres (écartement x 2.5), et s'accompagnait d'une augmentation sélective des macrophages CD206+ activés dans la voie alterne (M2) et d'une diminution relative des cellules satellites musculaires (p&lt;0.0001). Ces données suggèrent un rôle clé de la fibrose endomysiale (et des macrophages M2 profibrosant) et dans la sévérité clinique de la DMD. 3- Étude expérimentale. Ces éléments rendent nécessaire la mise au point d'un modèle expérimental de myofibrose dystrophique, la souris mdx présentant peu de fibrose et un déficit moteur modéré et tardif. Nous avons mis au point une nouvelle méthode de lésion musculaire focale profibrosante du tibialis antérieur chez la souris mdx (piqûres multiples quotidiennes pendant 15 jours). Une fibrose endomysiale attestée par un fort immunomarquage du collagène I (à 8, 30, 60 et 90 jours) a été quantifiée et corrélée à la perte de la force musculaire dans la patte lésée (comparée au muscle contralatéral). Ces résultats légitiment et préparent les futures stratégies thérapeutiques "anti-fibrosantes" dans la DMD</abstract> / The clinical heterogeneity of Duchenne muscular dystrophy (DMD) may prove a major obstacle to the interpretation of therapeutic trials but has not been subjected to systematic analysis. In a first part, we present a statistical analysis on two series of steroid-free patients with complete lack of dystrophin determined by Western blot. Series 1 consisting of 75 patients longitudinally evaluated for motor, respiratory, cardiac and cognitive functions by the same team (median follow-up: 10.5yrs) was subjected to exploratory data analysis whose main conclusion were confirmed by exploration of data obtained from 34 routinely evaluated patients (series 2). Main outcome measures were age at loss of ambulation and of onset of contractures, manual muscle testing (MMT), cardiac and respiratory functional tests, general intelligence assessment (IQ), educational level. Multivariate exploratory analysis of series 1 classified 70/75 patients into 4 clusters with distinctive intellectual and motor outcomes: A (congenital DMD, 20%): markedly poor intellectual and motor outcome; B (classical DMD, 28%): intermediate intellectual and poor motor outcome; C (moderate pure motor DMD, 22%): normal intelligence and delayed motor impairment; and D (severe pure motor DMD, 30%): normal intelligence and poor motor outcome. Group A patients had the most severe respiratory and cardiac involvement. Frequency of mutations upstream to exon 30 increased from group A to D, but genotype/phenotype correlations were restricted to cognition. Diagnostic accuracy tests showed that combination of "clinical onset &lt;2yrs" with "mental retardation" reliably assigned patients to group A (sensitivity 0.93, specificity 0.98). Combination of "lower limb MMT score&gt;6 at 8yrs" with "normal or borderline mental status" reliably assigned patients to group C (sensitivity: 1, specificity: 0.94). These early criteria were also predictive of "congenital DMD" and "moderate pure motor DMD" in series 2. In a second part, we included 25 steroid-free DMD patients in a multiparametric analysis plotting initial histological alterations in quadriceps muscle with 13 relevant clinical data collected by the same team over a long-term follow-up (mean&gt;10yrs). Elementary histological parameters (fiber size, hypercontracted fibers, necrotic/basophilic fibers, edema, endomysial and perimysial fibrosis, and fatty degeneration) were assessed by morphometry. Endomysial fibrosis was the sole myopathological parameter significantly correlated with poor motor outcome, assessed by quadriceps muscle strength, manual muscle testing of upper and lower limbs at 10yrs, and age at ambulation loss (all p&lt;0.002). Motor outcome and fibrosis were not correlated with genotype. Myofibers exhibited oxidative stress-induced protein alterations and became separated from capillaries by fibrosis, which was associated with both increase of CD206+ alternatively activated macrophages and relative decrease of CD56+ satellite cells (both p&lt;0.0001). This study provides firm basis for antifibrotic therapeutic strategies in DMD, and supports the view that alternatively activated macrophages, known to inhibit myogenesis while promoting collagen-producing cell formation, play a key role in myofibrosis. In the third experimental part, experiments were conducted on mdx mice at 6-8 weeks of age. Fifteen micropunctures were made daily in the right tibialis anterior (TA) muscle with micropins used for entomology (150 µm diameter) during 2 weeks. Our data suggest that repeated microinjuries of muscle deficient in dystrophin protein triggers a endomysial fibrotic process that stabilizes with time well associated with muscle strenght decrease. Endomysial fibrosis seems to be one of the target of therapy in DMD. This satisfactory model will be usefull to study the mechanisms of fibrosis process in dystrophin deficient muscle and to evaluate antifibrotic treatment

Neste trabalho foi desenvolvido um Dot-ELISA capaz de detectar anticorpos anti-Plasmodium vivax, anti-Plasmodium falciparum, anti-Trypanosoma cruzi e anti-Treponema pallidum, simultaneamente. O teste foi padronizado e aplicado em amostras de pacientes com malária, doença de Chagas e sífilis e comparado com testes de referência. Foi utilizado no estudo 52 amostras de pacientes com doença de Chagas, 43 pacientes com sífilis, 103 indivíduos com infecção presente (primo-infectado e não primo-infectados) ou passada de malária, indivíduos com anticorpos heterólogos, 30 indivíduos com leishmaniose 100 indivíduos saudáveis. O Dot-ELISA-Multi apresentou 100% de especificidade para todos os antígenos nas amostras de indivíduos saudáveis e com anticorpos heterólogos, com exceção do antígeno TESA que obteve 99%. A sensibilidade obtida foi de 100% em indivíduos chagásicos e 88% em pacientes com sífilis. Em indivíduos com malária a sensibilidade obtida foi de 90% para PvMSP119 (antígeno de P. vivax) e 47% para Pf-Zw (antígeno de P. falciparum). A positividade do teste em indivíduos não parasitados com histórico de malária foi de 92%. Nas amostras de malária observou-se que em indivíduos que tinham tido ultimo episódio de P. vivax, associação negativa foi observada entre o tempo passado desde o último episódio e reatividade de Dot-ELISAMulti PvMSP119, e associação positiva entre o número de episódios de malária e reatividade de Dot-ELISA-Multi Pf-Zw. Indivíduos cujo o último episódio foi por P. falciparum, o Dot-ELISA-Multi Pf-Zw apresentou associação positiva com o número de episódios ocorridos. O comparado com os testes de referência utilizados apresentou um nível muito bom de concordância para TESA, EAE, PvMSP119 e um nível bom de concordância para Pf-Zw / In the present study, a Dot-ELISA was assembled to test antibodies against Plasmodium vivax, Plasmodium falciparum, Trypanosoma cruzi and Treponema pallidum and was standardized and evaluated in serum samples from patients with malaria, Chagas disease and syphilis, in comparison with reference tests. The study was carried out on serum samples from 52 patients with chronic Chagas disease, 103 individuals with current (parasitemic) or past malaria (aparasitemic), 43 patients with syphilis, 30 with leishmaniosis, 21 individuals with heterologous antibodies and 100 blood donors. The diagnostic performance of Dot-ELISA-Multi for serum samples from patients with heterologous antibodies and from healthy blood donors, an overall 100% specificity was obtained for all antigens but TESA. A 100% sensitivity was observed in serum specimens from chronic-chagasic patients and 88% in serum specimens from syphilis patients. For malaria samples, the positivity was 90% for PvMSP119 and 47% for Pf-Zw antigen. In past malaria individuals, positivity was 92%. Sera from subjects who had had a P. vivax-malaria last episode presented negative association between time elapsed since their last malaria episode and results from Dot-ELISA-Multi PvMSP119; while positive association was observed between number of malaria episodes and results from Dot-ELISA-Multi Pf-Zw. For individuals who had had a P. falciparum-malaria last episode, Dot-ELISAMulti Pf-Zw results showed positive association with number of malaria episodes only. Altogether, concerning the reactivity of the five antigens of the Dot-ELISAMulti, as compared with their respective reference tests, we have observed a very good level of concordance for TESA, EAE, PvMSP119 and for Tp-Zw and a good level for Pf-Zw

Neste trabalho foi desenvolvido um Dot-ELISA capaz de detectar anticorpos anti-Plasmodium vivax, anti-Plasmodium falciparum, anti-Trypanosoma cruzi e anti-Treponema pallidum, simultaneamente. O teste foi padronizado e aplicado em amostras de pacientes com malária, doença de Chagas e sífilis e comparado com testes de referência. Foi utilizado no estudo 52 amostras de pacientes com doença de Chagas, 43 pacientes com sífilis, 103 indivíduos com infecção presente (primo-infectado e não primo-infectados) ou passada de malária, indivíduos com anticorpos heterólogos, 30 indivíduos com leishmaniose 100 indivíduos saudáveis. O Dot-ELISA-Multi apresentou 100% de especificidade para todos os antígenos nas amostras de indivíduos saudáveis e com anticorpos heterólogos, com exceção do antígeno TESA que obteve 99%. A sensibilidade obtida foi de 100% em indivíduos chagásicos e 88% em pacientes com sífilis. Em indivíduos com malária a sensibilidade obtida foi de 90% para PvMSP119 (antígeno de P. vivax) e 47% para Pf-Zw (antígeno de P. falciparum). A positividade do teste em indivíduos não parasitados com histórico de malária foi de 92%. Nas amostras de malária observou-se que em indivíduos que tinham tido ultimo episódio de P. vivax, associação negativa foi observada entre o tempo passado desde o último episódio e reatividade de Dot-ELISAMulti PvMSP119, e associação positiva entre o número de episódios de malária e reatividade de Dot-ELISA-Multi Pf-Zw. Indivíduos cujo o último episódio foi por P. falciparum, o Dot-ELISA-Multi Pf-Zw apresentou associação positiva com o número de episódios ocorridos. O comparado com os testes de referência utilizados apresentou um nível muito bom de concordância para TESA, EAE, PvMSP119 e um nível bom de concordância para Pf-Zw / In the present study, a Dot-ELISA was assembled to test antibodies against Plasmodium vivax, Plasmodium falciparum, Trypanosoma cruzi and Treponema pallidum and was standardized and evaluated in serum samples from patients with malaria, Chagas disease and syphilis, in comparison with reference tests. The study was carried out on serum samples from 52 patients with chronic Chagas disease, 103 individuals with current (parasitemic) or past malaria (aparasitemic), 43 patients with syphilis, 30 with leishmaniosis, 21 individuals with heterologous antibodies and 100 blood donors. The diagnostic performance of Dot-ELISA-Multi for serum samples from patients with heterologous antibodies and from healthy blood donors, an overall 100% specificity was obtained for all antigens but TESA. A 100% sensitivity was observed in serum specimens from chronic-chagasic patients and 88% in serum specimens from syphilis patients. For malaria samples, the positivity was 90% for PvMSP119 and 47% for Pf-Zw antigen. In past malaria individuals, positivity was 92%. Sera from subjects who had had a P. vivax-malaria last episode presented negative association between time elapsed since their last malaria episode and results from Dot-ELISA-Multi PvMSP119; while positive association was observed between number of malaria episodes and results from Dot-ELISA-Multi Pf-Zw. For individuals who had had a P. falciparum-malaria last episode, Dot-ELISAMulti Pf-Zw results showed positive association with number of malaria episodes only. Altogether, concerning the reactivity of the five antigens of the Dot-ELISAMulti, as compared with their respective reference tests, we have observed a very good level of concordance for TESA, EAE, PvMSP119 and for Tp-Zw and a good level for Pf-Zw

«Machine Learning» est un champ d'étude de l'intelligence artificielle qui se concentre sur des algorithmes capables d'adapter leur paramètres en se basant sur les données observées par l'optimisation d'une fonction objective ou d'une fonction de cout. Cette discipline a soulevé l'intérêt de la communauté de la recherche biomédicale puisqu'elle permet d'améliorer la sensibilité et la spécificité de la détection et du diagnostic de nombreuses pathologies tout en augmentant l'objectivité dans le processus de prise de décision thérapeutique. L'imagerie biomédicale est devenue indispensable en médecine, puisque plusieurs modalités comme l'imagerie par résonance magnétique (IRM), la tomodensitométrie et la tomographie par émission de positron sont de plus en plus utilisées en recherche et en clinique. L'IRM est la technique d'imagerie non-invasive de référence pour l'étude du cerveau humain puisqu'elle permet dans un temps d'acquisition raisonnable d'obtenir à la fois des cartographies structurelles et fonctionnelles avec une résolution spatiale élevée. Cependant, avec l'augmentation du volume et de la complexité des données IRM, il devient de plus en plus long et difficile pour le clinicien d'intégrer toutes les données afin de prendre des décisions précises. Le but de cette thèse est de développer des méthodes de « machine learning » automatisées pour la détection de tissu cérébral anormal, en particulier dans le cas de suivi de glioblastome multiforme (GBM) et de sclérose en plaques (SEP). Les techniques d'IRM conventionnelles (IRMc) actuelles sont très utiles pour détecter les principales caractéristiques des tumeurs cérébrales et les lésions de SEP, telles que leur localisation et leur taille, mais ne sont pas suffisantes pour spécifier le grade ou prédire l'évolution de la maladie. Ainsi, les techniques d'IRM avancées, telles que l'imagerie de perfusion (PWI), de diffusion (DKI) et la spectroscopie par résonance magnétique (SRM), sont nécessaires pour apporter des informations complémentaires sur les variations du flux sanguin, de l'organisation tissulaire et du métabolisme induits par la maladie. Dans une première étude de suivi de patients GBM, seuls les paramètres d'IRM avancés ont été explorés dans un relativement petit sous-groupe de patients. Les paramètres de PWI moyens, mesurés dans les régions d'intérêts (ROI) délimités manuellement, se sont avérés être d'excellents marqueurs, puisqu'ils permettent de prédire l'évolution du GBM en moyenne un mois plus tôt que le clinicien. Dans une seconde étude, réalisée sur un échantillon plus important que la précédente, la SRM a été remplacée par l'IRMc et la quantification de la PWI et du kurtosis de diffusion (DKI) a été réalisée de manière automatique. L'extraction des paramètres d'imagerie a été effectuée sur des segmentations semi-automatiques des tumeurs, réduisant ainsi le temps nécessaire au clinicien pour la délimitation du ROI de la partie de la lésion rehaussée au produit de contraste (CE-ROI). L'application d'un algorithme modifié de «boosting» sur les paramètres extraits des ROIs a montré une grande précision pour le diagnostic du GBM. Dans une troisième, une version modifiée des cartes paramétriques de réponse (PRM) est proposée pour prendre en compte la région d'infiltration de la tumeur, réduisant toujours plus le temps nécessaire pour la délimitation de la tumeur par le clinicien, puisque toutes les images IRM sont recalées sur la première. Deux façons de générer les RPM ont été comparées, l'une basée sur l'IRMc et l'autre basée sur la PWI, ces deux paramètres étant les meilleurs pour la discrimination de l'évolution du GBM, comme le montrent les deux études précédentes. Les résultats de cette étude montrent que l'emploi de PRM basés sur l'IRMc permet d'obtenir des résultats supérieurs à ceux obtenus avec les PRM basés sur la PWI [etc…] / Machine learning is a subdiscipline in the field of artificial intelligence, which focuses on algorithms capable of adapting their parameters based on a set of observed data, by optimizing an objective or cost function. Machine learning has been the subject of large interest in the biomedical community because it can improve sensitivity and/or specificity of detection and diagnosis of any disease, while increasing the objectivity of the decision-making process. With the late increase in volume and complexity of medical data being collected, there is a clear need for applying machine learning algorithms in multi-parametric analysis for new detection and diagnostic modalities. Biomedical imaging is becoming indispensable for healthcare, as multiple modalities, such as Magnetic Resonance Imaging (MRI), Computed Tomography, and Positron Emission Tomography, are being increasingly used in both research and clinical settings. The non-invasive standard for brain imaging is MRI, as it can provide structural and functional brain maps with high resolution, all within acceptable scanning times. However, with the increase of MRI data volume and complexity, it is becoming more time consuming and difficult for clinicians to integrate all data and make accurate decisions. The aim of this thesis is to develop machine learning methods for automated preprocessing and diagnosis of abnormal brain tissues, in particular for the followup of glioblastoma multiforme (GBM) and multiple sclerosis (MS). Current conventional MRI (cMRI) techniques are very useful in detecting the main features of brain tumours and MS lesions, such as size and location, but are insufficient in specifying the grade or evolution of the disease. Therefore, the acquisition of advanced MRI, such as perfusion weighted imaging (PWI), diffusion kurtosis imaging (DKI), and magnetic resonance spectroscopic imaging (MRSI), is necessary to provide complementary information such as blood flow, tissue organisation, and metabolism, induced by pathological changes. In the GBM experiments our aim is to discriminate and predict the evolution of patients treated with standard radiochemotherapy and immunotherapy based on conventional and advanced MRI data. In the MS experiments our aim is to discriminate between healthy subjects and MS patients, as well as between different MS forms, based only on clinical and MRSI data. As a first experiment in GBM follow-up, only advanced MRI parameters were explored on a relatively small subset of patients. Average PWI parameters computed on manually delineated regions of interest (ROI) were found to be perfect biomarkers for predicting GBM evolution one month prior to the clinicians. In a second experiment in GBM follow-up of a larger subset of patients, MRSI was replaced by cMRI, while PWI and DKI parameter quantification was automated. Feature extraction was done on semi-manual tumour delineations, thereby reducing the time put by the clinician for manual delineating the contrast enhancing (CE) ROI. Learning a modified boosting algorithm on features extracted from semi-manual ROIs was shown to provide very high accuracy results for GBM diagnosis. In a third experiment in GBM follow-up of an extended subset of patients, a modified version of parametric response maps (PRM) was proposed to take into account the most likely infiltration area of the tumour, reducing even further the time a clinician would have to put for manual delineating the tumour, because all subsequent MRI scans were registered to the first one. Two types of computing PRM were compared, one based on cMRI and one based on PWI, as features extracted with these two modalities were the best in discriminating the GBM evolution, according to results from the previous two experiments. Results obtained within this last GBM analysis showed that using PRM based on cMRI is clearly superior to using PRM based on PWI [etc…]