Serial passaging of primary human fibroblasts leads to the formation of non-dividing senescent cells by a process termed replicative senescence. This tissue culture-based methodology is currently used as a model system to determine the underlying mechanisms of in vivo cellular aging and tumor suppression. Senescence is regarded as an alternative pathway to apoptosis, where cells undergo multiple changes in metabolic and cellular signaling pathways in order to prevent proliferation but still maintain a metabolically-active cell. Whether or not this model accurately reflects in vivo processes is presently controversial; however, replicative senescence is currently the most applicable model through which one can investigate the underlying causes of human cellular aging in the context of controlled environmental stress over time. This work was directed at understanding the molecular processes involved in replicative senescence with specific emphasis on the role of the mitochondria. A series of experiments were performed to assess changes during the induction of replicative senescence under conditions of low (3%) and high (20%) oxygen levels. Measurements were made at the transcriptional, protein, and metabolite levels. Microscopy wasalso utilized to monitor changes in mitochondrial morphology and volume. While previous studies have evaluated specific pathways and/or products; this work combines a more complete metabolomic, genomic, proteomic, and morphological picture of cells undergoing senescence and oxidative stress. Considering the low cell population densities of primary adherent fibroblasts and the subsequent low concentrations of small polar metabolites involved in glycolysis and the TCA cycle, methodologies needed to be developed in order to optimize metabolite extraction and liquid chromatography-mass spectrometric analysis. Protein kinase and transcriptional microarrays were also performed in order to quantify the changes in activated/deactivated signaling cascades as well as gene expression and relate these findings to metabolomic data. Mitochondrial dynamics of cells at different age time points and under different oxygen conditions were also assessed including mitochondrial size, shape, membrane potential, and percent volume per cell volume using confocal microscopy. The results obtained not only confirm the major pathways involved in senescence (p53/p21, PTEN/p27, and RTK/Raf/MAPK) but also provide evidence at both the transcriptional and protein levels for additional senescence-associated pathways. The majority of the changes observed were related to pathways involved in cellular stress, cell cycle control, and the survival response. Metabolic data suggested a –pooling effect– of glycolysis and TCA precursor molecules due to attenuation in enzyme function; this theory was also supported by an observed up regulation of gene expression as a compensatory mechanism. Mitochondria exhibited changes in membrane potential as well as volume and percent volume per cell which suggested compensatory hypertrophy and/or attenuation of mitochondrial fission processes. When the aforementioned analyses are tied together, a “theoretical model of senescence” can be formulated and is characterized by increased metabolic protein and associated metabolite levels due to attenuation in their respective enzyme function, resulting in increases in expression of their associated genes as a compensatory mechanism. / Ph. D.

La thérapie de pleine conscience est considérée comme la nouvelle orientation de la thérapie cognitive comportementale. Elle trouve son origine principalement avec le travail de Kabat-Zinn (1979- 2009), le président du centre CFM : Centre for Mindefulness in médecine, qui a montré que la thérapie de pleine conscience est une thérapie autonome capable de diminuer des symptômes pathologiques et influencer la personnalité pour aboutir à des changements cognitifs parfonds. Dans notre travail l’anorexie mentale a été choisie comme une pathologie pouvant être traitée par cette thérapie, ce qui n’avait pas été effectué jusqu’à présent. Les séances se sont déroulées avec des patientes hospitalisées à Lyon et à St. Etienne. Les résultats obtenus ont montré que la prise en charge par « la pleine consciences », a fait diminué les symptômes pathologiques d’anorexie mental (physique, psychique et cognitifs), et que les patientes, après la thérapie, ont présenté un locus de contrôle interne par rapport au début de thérapie et par rapport au groupe contrôle ; qu’elles utilisent moins le coping émotion et plus le coping problème et le coping soutien social par rapport au début la thérapie et par rapport au groupe de contrôle. / The Mindfulness therapy is considered the new direction of cognitive behavioral therapy. It started mainly with the work of Kabat- Zinn (1979 - 2009) President of CFM Centre: Centre for Medicine in Mindefulness where he interested in managing stress using mindfulness. This study is an attempt to make the therapy of mindfulness as an independent therapy by itself is able to reduce disease symptoms and influence on personality to cognitive changes Profound. It targets to show that this type of therapy is far from being a simple tool to manage stress. Anorexia nervosa has been selected as pathology to be treated by this therapy, which held its session in patient hospitalized in Lyon and St. Etienne. The results showed that the treatment with the Mindfulness had reduced the pathological symptoms of anorexia nervosa (physical, emotional and cognitive), and that patients, after therapy, had became with a locus of control internal Compared with the beginning of treatment, and with the control group, they used less the coping emotional and coping problem and coping social support compared with the start of therapy and the control group.

La survie des cellules cancéreuses dépend d’une activité énergétique et biosynthétique accrue et la glutamine participe à de nombreux processus nécessaires à cette adaptation métabolique. Dans les leucémies aiguës myéloïdes (LAM), la croissance et la prolifération sont favorisées par l’activation anormale de plusieurs voies de signalisation, et notamment par la voie mTORC1. Les acides aminés essentiels, et en particulier la leucine, sont indispensables à l’activation de mTORC1. La glutamine est captée par la cellule via le transporteur SLC1A5 et permet ensuite l’entrée de la leucine via le transporteur bidirectionnel SLC7A5. La concentration en glutamine est donc une étape limitante dans l’activation de mTORC1 par la leucine. Nous avons étudié les effets de la privation en glutamine dans les LAM à l’aide de différents outils (milieu sans glutamine, shARN inhibant l’expression du transporteur de la glutamine SLC1A5 et la drogue L-asparaginase, qui a une activité de glutaminase extracellulaire), et observé une inhibition de mTORC1 et de la synthèse protéique. L’inhibition du transporteur SLC1A5 inhibe la pousse tumorale dans un modèle de xénotransplantation. La L-asparaginase inhibe mTORC1 et induit une apoptose de façon proportionnelle à son activité glutaminase et complètement indépendante de la concentration en asparagine. La privation en glutamine induit l’expression de la glutamine synthase et l’autophagie, et ces deux processus peuvent être des mécanismes de résistance intrinsèques ou acquis dans certaines lignées leucémiques. L’apoptose induite par la privation en glutamine n’est cependant pas liée à l’inhibition de mTORC1, puisqu’elle n’est pas diminuée par l’utilisation d’un mutant de mTOR non inhibé par la privation en glutamine. Nous nous sommes donc intéressés à une autre voie dépendante de la glutamine dans de nombreux cancers, la phosphorylation oxydative. L’étape initiale du catabolisme intracellulaire de la glutamine est la conversion de la glutamine en glutamate par des enzymes appelées glutaminases. Différentes isoformes des glutaminases existent qui sont codées chez l’homme par les gènes GLS1 et GLS2. Le glutamate est ensuite transformé en α-cétoglutarate, intermédiaire du cycle TCA. Dans les lignées de LAM, la privation en glutamine inhibe la phosphorylation oxydative mitochondriale. Nous avons observé que la protéine glutaminase C (GAC), une des isoformes de GLS1, est constamment exprimée dans les LAM mais aussi dans les progéniteurs hématopoïétiques CD34+ normaux. L’inhibition d’expression de la GLS1 par des shARN inductibles ou bien par le composé CB-839 réduit la phosphorylation oxydative, conduisant à une inhibition de prolifération et à une induction d’apoptose des cellules leucémiques. L’invalidation génétique de la GLS1 inhibe la formation de tumeur et améliore la survie des souris dans un modèle de xénotransplantation. A l’inverse, le ciblage de la GLS1 n’a pas d’effets cytotoxiques ni cytostatiques sur les progéniteurs hématopoïétiques normaux. Ces effets anti-leucémiques sont inhibés par l’adjonction d’α-cétoglutarate, et ceux induit par le CB-839 sont abrogés lorsqu’est exprimé de façon ectopique un mutant GACK320A hyperactif, attestant du rôle essentiel du maintien d’un cycle TCA actif dans les cellules de LAM. Enfin, nous montrons que l’inhibition de la glutaminolyse active la voie d’apoptose mitochondriale intrinsèque et agit en synergie avec l’inhibition spécifique de BCL-2 par l’ABT-199. Ces résultats démontrent que le ciblage spécifique de la glutaminolyse est une autre façon d’exploiter l’addiction à la glutamine des cellules leucémiques de LAM et que le maintien d’un cycle TCA actif est essentiel à la survie de ces cellules. / Cancer cells survival is dependent on high energetic and biosynthetic activity, and glutamine is involved in many metabolic processes necessary for this adaptation. In acute myeloid leukemia (AML), growth and proliferation are promoted by activation of several signaling pathways, including mTORC1. Essential amino acids, in particular leucine, are required for mTORC1 activation. Glutamine enters into the cell via the SLC1A5 transporter and then allows the input of leucine via the bidirectional SLC7A5 transporter. Therefore, the intracellular glutamine concentration is a limiting step in the activation of mTORC1 by leucine. We studied the effects of glutamine deprivation in AML using different tools (medium without glutamine, shRNA against the SLC1A5 glutamine transporter and the drug L-asparaginase, which has an extracellular glutaminase activity) and observed mTORC1 and protein synthesis inhibition. SLC1A5 transporter knockdown inhibits tumor growth in a xenotransplantation model. L-asparaginase inhibits mTORC1 and induces apoptosis in proportion to its glutaminase activity and independently of asparagine concentration. Glutamine privation induces the expression of glutamine synthase and autophagy, and these two processes are involved in the resistance to glutamine privation in some leukemic cell lines. However, apoptosis induced by glutamine privation is not related to the inhibition of mTORC1, since it is not modified in the presence of a constitutively active mutant of mTOR. We next focused on the oxidative phosphorylation, another glutamine dependent pathway in many cancers. The initial step of the intracellular catabolism of glutamine is the conversion of glutamine to glutamate by enzymes called glutaminases. Different glutaminases isoforms exist that are encoded by the GLS1 and GLS2 genes. Glutamate is then converted to α-ketoglutarate, an essential TCA cycle intermediate. In AML cell lines, we observed that glutamine privation inhibits mitochondrial oxidative phosphorylation. The protein glutaminase C (GAC), an isoform of GLS1, is constantly expressed in AML but also in normal CD34 + hematopoietic progenitors. The knockdown of GLS1 by inducible shRNA or by the CB-839 compound reduced oxidative phosphorylation, leading to proliferation inhibition and apoptosis induction in leukemia cells. Genetic invalidation of GLS1 inhibits tumor formation and improves survival of mice in a xenograft model. Conversely, the targeting of GLS1 has no cytotoxic or cytostatic effects on normal hematopoietic progenitors. These anti-leukemic effects are inhibited by the addition of α-ketoglutarate, and those induced by the CB-839 are suppressed in the presence of an ectopically expressed GACK320A hyperactive mutant, confirming the essential role of maintaining an active TCA cycle in AML cells. Finally, we showed that glutaminolysis inhibition induces the intrinsic mitochondrial pathway of apoptosis and acts synergistically with the specific inhibition of BCL-2 by ABT-199. These results demonstrate that specific targeting of glutaminolysis is another way to exploit glutamine addiction in AML and that an active TCA cycle in essential for AML cell survival.

The tricarboxylic acid (TCA) cycle is one of the central pathways in respiration and also plays an important role in a variety of metabolic processes including the synthesis of secondary metabolites and the provision of carbon skeletons for ammonium assimilation and amino acid biosynthesis. Effective regulation of these multiple demands on the TCA cycle is likely to be very important for plant fitness. One way that this regulation could be achieved is through metabolite channelling. This occurs when metabolites are transferred between enzyme active sites without diffusing into the bulk aqueous phase of the cell, and is known to be important in regulating demands in metabolic pathways. Although there is evidence that metabolite channelling exists in animals, there have been no attempts to investigate it in plant. The first aim of this thesis was therefore to investigate whether metabolite channelling exists in the plant TCA cycle. Isotope dilution experiments were developed to investigate metabolite channelling, and were able to show that metabolite channelling was present between certain enzymes of the TCA cycle in both S. tuberosum and A. thaliana mitochondria. The second aim of the thesis was investigate whether metabolite channelling is important in regulating the TCA cycle in plant mitochondria. The pattern of metabolite channelling did not change in mitochondria isolated from the light and the dark, or from mitochondria with increased or decreased TCA cycle rates, but it was not possible to say whether the metabolite channelling altered in a quantitative fashion. Overall the thesis provides the first direct evidence of channelling in the TCA cycle in plants, and further work should help to elucidate what role, if any, it plays.

abstract: Widespread use of chlorinated solvents for commercial and industrial purposes makes co-occurring contamination by 1,1,1-trichloroethane (TCA), trichloroethene (TCE), and 1,4-dioxane (1,4-D) a serious problem for groundwater. TCE and TCA often are treated by reductive dechlorination, while 1,4-D resists reductive treatment. Aerobic bacteria are able to oxidize 1,4-D, but the biological oxidation of 1,4-D could be inhibited TCA, TCE, and their reductive transformation products. To overcome the challenges from co-occurring contamination, I propose a two-stage synergistic system. First, anaerobic reduction of the chlorinated hydrocarbons takes place in a H2-based hollow-fiber “X-film” (biofilm or catalyst-coated film) reactor (MXfR), where “X-film” can be a “bio-film” (MBfR) or an abiotic “palladium-film” (MPfR). Then, aerobic removal of 1,4-D and other organic compounds takes place in an O2-based MBfR. For the reductive part, I tested reductive bio-dechlorination of TCA and TCE simultaneously in an MBfR. I found that the community of anaerobic bacteria can rapidly reduce TCE to cis-dichloroethene (cis-DCE), but further reductions of cis-DCE to vinyl chloride (VC) and VC to ethene were inhibited by TCA. Also, it took months to grow a strong biofilm that could reduce TCA and TCE. Another problem with reductive dechlorination in the MBfR is that mono-chloroethane (MCA) was not reduced to ethane. In contrast, a film of palladium nano-particles (PdNPs), i.e., an MPfR, could the simultaneous reductions of TCA and TCE to mainly ethane, with only small amounts of intermediates: 1,1-dichloroethane (DCA) (~3% of total influent TCA and TCE) and MCA (~1%) in continuous operation. For aerobic oxidation, I enriched an ethanotrophic culture that could oxidize 1,4-D with ethane as the primary electron donor. An O2-based MBfR, inoculated with the enriched ethanotrophic culture, achieved over 99% 1,4-D removal with ethane as the primary electron donor in continuous operation. Finally, I evaluated two-stage treatment with a H2-based MPfR followed by an O2-MBfR. The two-stage system gave complete removal of TCA, TCE, and 1,4-D in continuous operation. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018

An important cause of pulmonary arterial hypertension (PAH) in children with congenital heart disease (CHD) is increased pulmonary blood flow (PBF). To gain a better understanding of the disease process, the changes in biochemical pathways and metabolism of pulmonary arterial smooth muscle cells (PASMCs) were studied using a unique surgical ovine model of increased pulmonary blood flow. PASMCs isolated from 4-week-old lambs with increased PBF (shunt) showed lower oxygen consumption rates and lower extracellular acidification rates linked to glutamine metabolism when compared to controls. Shunt and control PASMCs both exhibited a switch into the reverse tricarboxylic acid (TCA) cycle, while only shunt cells showed a decrease of glucose being transformed into Acetyl CoA to enter the forward TCA cycle. Shunt PASMCs also demonstrated increased levels of yes-associated protein 1 (YAP1) expression in the nucleus. These results indicate changes in glutamine metabolism, glucose metabolism, and protein signaling cascades associated with increased mechanical forces in the setting of increased PBF, as seen in PAH in children with CHD.

The micro-enterprise (MCE) represents by far the largest category of businesses in most industrialised economies but until now it has not been recognised as an important participant in the foreign market. Much has been written about how larger firms internationalise through the gradual acquisition of knowledge and resources, although there is a paucity of literature on how the MCE exploits international markets often despite the absence of such acquisitions. This thesis proposes that building a portfolio of relationships is critical in facilitating both market entry and subsequent outcomes. A more detailed investigation of this process helps reveal precisely how MCE internationalisation is largely a function of its specific relationship building efforts.Employing a multiple case study approach, in-depth interviews were held with founders and directors from seven MCE's, purposely selected from three main centres of commercial activity in New Zealand. Interview participants were encouraged to provide detailed longitudinal retrospections of their firm's internationalisation journey, with a particular emphasis on precisely how resource constraints were overcome during this process. All interviews were recorded and transcribed, and together with other confirmatory data sources, these formed the canon of evidence used for ongoing analysis and interpretation. The whole research process was an iterative one with observations made from earlier cases being challenged and refined through the consideration of data from subsequent cases.Several key findings emerged from this study. Firstly, internationalisation is of considerable significance to the MCE in that it expands product and market opportunities, improves operational competencies, and provides an outlet for the achievement of both financial and relational goals. Secondly, key relationships developed during this process include internal, manufacturer/supplier, distributor, support, EPO, and end-user types. Thirdly, MCE's gravitate towards adopting either a social exchange (characterised by trust, commitment and social norms) or transaction cost analysis (characterised by contractual mechanisms) approach to developing these relationship types. Critical to this finding though and previously unobserved in the literature, is that within the context of a social exchange or transaction cost analysis approach, governance (bilateral or unilateral/market) may be observed as a separate construct. Finally, the MCE adopting a social exchange approach overall achieves more robust international outcomes particularly in respect to increased cost efficiencies and new market opportunities.Although no statistical inferences can be drawn from the findings of this study, some important generalisations to theory can be made in respect to the manner in which small firm internationalisation is currently modelled. It is suggested that this research has begun to address the issue by proposing that the quality of relationships is central to the success of the smallest of internationalising concerns. Specifically, sequential knowledge, network, and resource based views, need to better incorporate the moderating role that the relational paradigm has on international progress. To this end it has been demonstrated that the precise underpinnings of the relationship can have a determining effect on both the rate and cost of international progress. Furthermore, managers may also benefit from these findings by improving both their relationship filtering and nurturing processes.

A study was carried out in a sedimentary fractured rock site located in south central Wisconsin, US, which was impacted by DNAPL releases estimated to occur in the 1950’s and 1960’s. The majority of the DNAPL has accumulated in the upper portion of the Lone Rock Formation at a depth between 140 and 180 ft bgs referred as Layer 5 in this study. A groundwater VOC plume of more than 3km long has formed in this Layer. The DNAPL is mainly composed of 1,1,1-TCA, PCE, TCE and BTEX, while large amounts of biodegradation products such as cis-DCE and 1,1-DCA are present in the plume. Long term VOC data have been collected at the site and diverse geological and hydrogeological techniques have been applied to have a better understanding of the DNAPL history and behavior of the VOC plume. Evidence of biodegradation was also documented near the DNAPL source in these studies. The thesis objectives of the present study aimed first to have a better understanding of the long term contaminant distribution and degradation history at the site. This objective was accomplished reviewing the VOC historical concentration data collected from 1992 to 2006 in the wells tapping the most contaminated. hydrogeological unit in the bedrock (Layer 5) and in the overburden aquifer (referred as Layer 2). The second objective aimed to evaluate the current degree or extent of biodegradation of chlorinated compounds, which was accomplished evaluating the current groundwater redox conditions and using a combined analysis of VOC concentration and carbon isotope data collected in groundwater in September 2007. The historical data collected between1992 to 2006 showed the degradation of the VOC plume in Layer 5 was controlled by the availability of electron acceptors and redox conditions in the fracture bedrock aquifer. This pattern and the extension of the VOC plume were linked to different DNALP pumping events in the source zone and the operation of a Hydraulic Barrier System. The current geochemical and isotope study showed a different pattern of biodegradation of chlorinated compounds in different parts of the plume. The cis-DCE tend to accumulate in the area from the source to the middle of the plume and around 80 % of biodegradation of 1,1,1-TCA to 1,1-DCA was observed in this area. The fringes of the plume were characterized by a dominant presence of TCE and 1,1,1 TCA. These patterns were linked to different redox conditions and amount of electron acceptors. The cis-DCE dominated area is characterized by anaerobic conditions and the presence of relative high amount of BTEX. The TCE-dominated area is under aerobic condition and no BTEX was found in this area. The operation of the Hydraulic Barrier System seems to have change redox condition which influenced the extent of degradation in the plume, especially in the area between the extraction wells. The formation of large amounts of VC in Layer 2 and the more reducing (at least sulfate reducing and maybe methanogenic conditions) of the groundwater in this Layer compared to Layer 5 confirmed the extent of VOC biodegradation is linked to the availability of electron donors. This study provides information about the current degree of the biodegradation of chlorinated compounds at a fracture rock site. This information is very valuable for the evaluation of natural attenuation as strategy for long term plume management or for future remediation strategies such as biostimulation or bioaugmentation at the site. This study also shows the present and long term behavior of the chlorinated compounds (degradation history) in the most contaminated hydrogeologic unit (Layer 5), has mainly been controlled by plume management strategies including DNAPL pumping in the source and the creation of a Hydraulic Barrier System. The ketones and BTEX, that acted as electron donors and carbon substrate for the microbial community responsible for the dechlorination of chlorinated compounds were shown to have controlled the past and current redox conditions and thus the degree and potential of biodegradation of chlorinated ethenes and chlorinated ethanes at the study site.

A study was carried out in a sedimentary fractured rock site located in south central Wisconsin, US, which was impacted by DNAPL releases estimated to occur in the 1950’s and 1960’s. The majority of the DNAPL has accumulated in the upper portion of the Lone Rock Formation at a depth between 140 and 180 ft bgs referred as Layer 5 in this study. A groundwater VOC plume of more than 3km long has formed in this Layer. The DNAPL is mainly composed of 1,1,1-TCA, PCE, TCE and BTEX, while large amounts of biodegradation products such as cis-DCE and 1,1-DCA are present in the plume. Long term VOC data have been collected at the site and diverse geological and hydrogeological techniques have been applied to have a better understanding of the DNAPL history and behavior of the VOC plume. Evidence of biodegradation was also documented near the DNAPL source in these studies. The thesis objectives of the present study aimed first to have a better understanding of the long term contaminant distribution and degradation history at the site. This objective was accomplished reviewing the VOC historical concentration data collected from 1992 to 2006 in the wells tapping the most contaminated. hydrogeological unit in the bedrock (Layer 5) and in the overburden aquifer (referred as Layer 2). The second objective aimed to evaluate the current degree or extent of biodegradation of chlorinated compounds, which was accomplished evaluating the current groundwater redox conditions and using a combined analysis of VOC concentration and carbon isotope data collected in groundwater in September 2007. The historical data collected between1992 to 2006 showed the degradation of the VOC plume in Layer 5 was controlled by the availability of electron acceptors and redox conditions in the fracture bedrock aquifer. This pattern and the extension of the VOC plume were linked to different DNALP pumping events in the source zone and the operation of a Hydraulic Barrier System. The current geochemical and isotope study showed a different pattern of biodegradation of chlorinated compounds in different parts of the plume. The cis-DCE tend to accumulate in the area from the source to the middle of the plume and around 80 % of biodegradation of 1,1,1-TCA to 1,1-DCA was observed in this area. The fringes of the plume were characterized by a dominant presence of TCE and 1,1,1 TCA. These patterns were linked to different redox conditions and amount of electron acceptors. The cis-DCE dominated area is characterized by anaerobic conditions and the presence of relative high amount of BTEX. The TCE-dominated area is under aerobic condition and no BTEX was found in this area. The operation of the Hydraulic Barrier System seems to have change redox condition which influenced the extent of degradation in the plume, especially in the area between the extraction wells. The formation of large amounts of VC in Layer 2 and the more reducing (at least sulfate reducing and maybe methanogenic conditions) of the groundwater in this Layer compared to Layer 5 confirmed the extent of VOC biodegradation is linked to the availability of electron donors. This study provides information about the current degree of the biodegradation of chlorinated compounds at a fracture rock site. This information is very valuable for the evaluation of natural attenuation as strategy for long term plume management or for future remediation strategies such as biostimulation or bioaugmentation at the site. This study also shows the present and long term behavior of the chlorinated compounds (degradation history) in the most contaminated hydrogeologic unit (Layer 5), has mainly been controlled by plume management strategies including DNAPL pumping in the source and the creation of a Hydraulic Barrier System. The ketones and BTEX, that acted as electron donors and carbon substrate for the microbial community responsible for the dechlorination of chlorinated compounds were shown to have controlled the past and current redox conditions and thus the degree and potential of biodegradation of chlorinated ethenes and chlorinated ethanes at the study site.

The central scientific objective of this thesis was to take a broad multidisciplinary approach to make use of the full potential information to battle EDs, utilizing an interactive and translational approach running from basic science through to the clinic. In our studies we assessed a.) clinical factors and comorbidity [namely substance use in EDs (Studies 1 to 3)], b.) psychosocial, behavioural and environmental correlates of EDs (Studies 4 to 7) and c.) treatment effectiveness of specific forms of ED interventions (Studies 8 to 9). Our first line of investigation comprised Studies 1 to 3 and assessed the comorbidity of substance use in EDs. The results of these studies suggest that compared to healthy controls, substance use was higher in individuals with EDs (Studies 1 and 3), that the presence of a family history of alcohol dependence was associated with the comorbidity of EDs and substance use (Study 2) that substance use was particularly prevalent in patients with bulimic characteristics (Studies 1 to 3) and that EDs and substance abuse may represent expressions of a fundamental predisposition to addictive behaviour possibly related to the genetically influenced traits such as novelty seeking (Study 2). Furthermore, we revealed some significant differences for the specific forms of drugs in people with EDs (Studies 1 and 3), which emphasize the significance of assessing various drug types in EDs. Finally we also observed cross-cultural differences across various European countries in the prevalence of substance use in EDs and healthy controls (Study 3).The second research area was labelled psychological, behavioural and environmental correlates of EDs. In our animal study (Study 4) we found that contextual conditioning of eating response was more effective when high than low density caloric food was used. This result indicates that animal models are useful for analyzing and identifying human-animal links in feeding related behaviours. Studies 5 and 6 assessed which early individual and family eating patterns play a role in the development of EDs. Our findings agree with the growing body of research indicating that a variety of environmental and social factors are associated with dysfunctional individual and family eating patterns (e.g. food used as individualization, control and rules about food) during the first years of life and which if not detected on time could lead to a subsequent ED. Conversely, healthy eating (including eating breakfast) was negatively linked to the development of a subsequent ED. Only a few differences across ED subtypes were observed. Finally some cross-cultural differences also emerged (Study 6).In Study 7 we compared anger expressions in individuals with EDs and healthy controls and explored the relation among ED symptoms, comorbid psychopathology, personality traits and impulsive behaviours. The results indicated that individuals with EDs obtained significantly higher scores than controls on maladaptive anger expressions. When different purging methods were assessed independently, the frequency of laxative use was associated with anger suppression. ED symptoms and specific personality traits were also positively associated to different anger expressions. At last, we observed that inappropriate anger expressions were related to self-harming behaviours.Finally our last research line assessed the effectiveness of various treatments for EDs. In Study 8 we compared full and subthreshold BN in terms of personality, clinical characteristics and short-term response to a psychoeducational therapy. The results showed that full-BN and sub-BN share common psychopathological symptoms and personality traits. Furthermore, no differences in therapy outcome were observed in terms of general ED symptomatology and psychopathology. In Study 9 we described and assessed a non-symptom oriented CBT treatment in a congenitally blind women. A dramatic reduction in ED symptoms was observed after the maintaining and triggering factors had been reduced.To conclude, relatively little research has been performed towards understanding the aetiology of EDs. The findings from our investigations represent a major enhancement in the state of the art of EDs, and lead to the development of a new overall etiological model of EDs. The model we propose is a general understanding of how various ED predisposing and precipitating factors might eventually lead to EDs, and maintain the course of a disorder. Future work should address the effects of genes, environment and gene-environment interaction on the development and maintenance of EDs. Of specific interest is the query of which of these factors are non-specifically related to mental disorders and which factors may be more explicit factors that predispose an individual to EDs and related states, but not to mental disorders in general. The answers to these questions should hopefully become perceptible in the next couple of years. / El objetivo principal de esta tesis ha sido el abordar los Trastornos de la alimentación (TCA) desde una aproximación multidisciplinar, que nos ayude a combatir los TCA desde una perspectiva traslacional, en la que confluyan investigaciones básicas y aplicadas. En nuestros estudios hemos analizado en profundidad los siguientes aspectos: a.) Factores clínicos y comorbilidad [especialmente abuso de sustancias en TCA] (Estudios 1 a 3); b.) Correlatos psicosociales, conductuales y ambientales en TCA (Estudios 4 a 7); y c.) Eficacia de tratamientos específicos en TCA (Estudios 8 a 9). Nuestra primera línea de investigación (Estudios 1-3), ha estudiado la comorbilidad de abuso de sustancias en TCA. Los resultados de estos estudios sugieren que: a) abuso de sustancias es más prevalente en TCA que en sujetos de control (Estudios 1 y 3); b) la presencia abuso de sustancias en pacientes con TCA, está asociada a historia familiar previa de dependencia de alcohol (Estudio 2); c) abuso de sustancias es especialmente prevalente en pacientes con características bulímicas (Estudios 1 a 3); y d) que presencia de abuso de sustancias en TCA puede ser expresión de una predisposición a conductas adictivas, cuya susceptibilidad viene determinada por rasgos de personalidad específicos (búsqueda de sensaciones) (Estudio 2). Asimismo, encontramos aspectos diferenciales en TCA, en base al tipo de droga que consumen (Estudio 1 y 3), hecho que enfatiza la importancia de evaluar los distintos tipos de drogas utilizados por estos pacientes. Finalmente, encontramos diferencias culturales entre distintos países europeos, respecto a la prevalencia de abuso de sustancias en TCA, al ser comparados con grupos de control (estudio 3).Como segunda área de investigación, nos centramos en aspectos psicológicos, conductuales y ambientales en TCA. En un estudio, realizado siguiendo un modelo animal (estudio 4), encontramos que el condicionamiento contextual de respuesta alimentaria es más efectivo cuando es utilizado un alimento con alta densidad calórica, que cuando se utiliza un alimento con baja densidad calórica. Estos resultados sugieren qué modelos animales son útiles a la hora de analizar e identificar asociaciones entre comportamiento en humanos y animales, respecto a su conducta alimentaria.En los estudios 5 y 6 se analizaron en qué medida conductas alimentarias tempranas y patrones alimentarios en la familia, influyen en la aparición posterior de un TCA. Los resultados de estos estudios sugieren, en concordancia con un creciente volumen estudios recientes, la influencia que poseen aspectos ambientales y sociales en el desarrollo posterior de una conducta alimentaria anormal (p.e., control y reglas entorno a la alimentación). Por contrario, patrones alimentarios regulares (p.e., desayunar antes de ir al colegio) se encontró negativamente asociado (factor protector) a subsecuente desarrollo de un TCA. Asimismo, fueron encontradas limitadas diferencias entre subtipos diagnósticos, aunque algunas hacían referencia al contexto cultural (estudio 6).En el estudio 7 comparamos la expresión de ira en sujetos con un TCA y un grupo control, y analizamos su asociación con sintomatología alimentaria, psicopatología general comórbida, rasgos de personalidad y conductas impulsivas. Nuestros resultados indicaron que pacientes con TCA manifestaban sentimientos de ira de forma más inadecuada que grupos control. Al analizar los distintos procedimientos de purga, la frecuencia de abuso de laxantes iba asociada a supresión de sentimientos de ira.La sintomatología alimentaria y algunos rasgos de personalidad se asociaban a determinadas formas inadecuadas de expresión de sentimientos. Asimismo, observamos que una inadecuada expresión de sentimientos en TCA se asociaba con una mayor frecuencia de conductas autoagresivas.Finalmente, en nuestra última línea de investigación analizamos la eficacia de distintos tipos de tratamiento en TCA. En el estudio 8 comparamos casos totales y parciales de Bulimia nerviosa, en base rasgos de personalidad, sintomáticas alimentaria, psicopatología general y respuesta a un tratamiento de carácter psicoeducativo. Los resultados indicaron que los casos totales y parciales de BN comparten similitudes sintomáticas, psicopatológicas y de personalidad. Asimismo, no se obtuvieron diferencias respecto a la respuesta al tratamiento entre ambos grupos de pacientes. En el estudio 9, describimos y evaluamos un tratamiento cognitivo-conductual no centrado en los síntomas alimentarios, en una paciente ciega. En este caso, fue constatada una drástica reducción de los síntomas alimentarios tras este tipo de tratamiento.En conclusión, hasta el momento, existen escasas referencias en la literatura que sirvan para esclarecer los aspectos etiopatológicos implicados en TCA. Los resultados obtenidos en nuestras investigaciones ayudan sobre el conocimiento actual de TCA, y contribuyen al desarrollo de un nuevo modelo multimodal de entendimiento de éstos. El modelo que proponemos combina la interacción de diversos factores (predisponentes, precipitantes y mantenedores). Trabajos futuros deberían prestar atención a la relevancia que tienen factores genéticos, ambientales e interacción genes-ambiente, en el desarrollo y mantenimiento de los TCA. Un especial interés presenta la pregunta de cuáles de estos factores son específicos para trastornos mentales y cuáles los son para TCA de forma específica. / RESUM:L'objectiu principal d'aquesta tesi ha estat l'abordar els Trastorns de la conducta alimentària (TCA) des d'una aproximació multidisciplinar, que ens ajudi a combatre'ls des d'una perspectiva traslacional, en la que conflueixin investigacions bàsiques i aplicades. En els nostres estudis hem analitzat en profunditat els següents aspectes: a.) Factors clínics i comorbilitat [especialment abús de substàncies en TCA] (Estudis 1 a 3); b.) Correlats psicosocials, conductuals i ambientals en TCA (Estudis 4 a 7); i c.) Eficàcia de tractaments específics en TCA (Estudis 8 a 9).La nostra primera línia d'investigació (Estudis 1 a 3), ha estudiat la comorbilitat d'abús de substàncies en TCA. Els resultats d'aquests estudis suggereixen que: a) l'abús de substàncies és més prevalent en TCA que en subjectes control (Estudis 1 i 3); b) la presència d'abús de substàncies en pacients amb TCA, està associada a història familiar prèvia de dependència d'alcohol (Estudi 2); c) l'abús de substàncies és especialment prevalent en pacients amb característiques bulímiques (Estudis 1 a 3); i d) que la presència d'abús de substàncies en TCA pot ser expressió d'una predisposició a conductes addictives, la susceptibilitat de les quals ve determinada per trets de personalitat específics (recerca percaça de sensacions) (Estudi 2). Així mateix, trobem aspectes diferencials en TCA, en base al tipus de droga que consumeixen (Estudis 1 i 3), fet que emfatitza la importància d'avaluar els diferents tipus de drogues utilitzats per aquests pacients. Finalment trobem diferències culturals entre distints països europeus, respecte a la prevalença d'abús de substàncies en TCA, al ser comparats amb grups control (Estudi 3).Com a segona àrea d'investigació, ens centrem en aspectes psicològics, conductuals i ambientals en TCA. En un estudi realitzat seguint un model animal (Estudi 4), trobem que el condicionament contextual de resposta alimentària és més efectiu quan s'utilitza un aliment amb alta densitat calòrica, que quan se'n utilitza un amb baixa densitat calòrica. Aquests resultats suggereixen que els models animals són útils a l'hora d'analitzar i identificar associacions entre comportament en humans i animals, respecte la seva conducta alimentària.En els estudis 5 i 6 es varen analitzar fins a quin punt conductes alimentàries primerenques i patrons alimentaris en la família influeixen en l'aparició posterior d'un TCA. Els resultats d'aquests estudis suggereixen, en concordància amb un volum creixent d'estudis recents, la influència que tenen aspectes ambientals i socials en el desenvolupament posterior d'una conducta alimentària anormal (per exemple, control i normes entorn a l'alimentació). Tanmateix, patrons alimentaris regulars (per exemple, esmorzar abans d'anar a l'escola) estaven negativament associats (factor protector) al subseqüent desenvolupament d'un TCA. Així mateix, es varen trobar diferències limitades entre subtipus diagnòstics. Finalment, es varen trobar algunes diferències en relació al context sociocultural. (Estudi 6).En l'estudi 7 vàrem comparar expressió d'ira en subjectes amb un TCA i un grup control, i vàrem analitzar la seva associació amb simptomatologia alimentària, psicopatologia general comòrbida, trets de personalitat i conductes impulsives. Els nostres resultats varen indicar que pacients amb TCA manifestaven sentiments d'ira de forma més inadequada que grups control. A l'analitzar els diferents procediments de purga, la freqüència d'abús de laxants anava associada a la supressió de sentiments d'ira.La simptomatologia alimentària i determinats trets de personalitat, s'associaven a determinades formes inadequades d'expressió de sentiments. Així mateix, vàrem observar que una expressió inadequada de sentiments en TCA anava associada a una freqüència major de conductes autoagressives.Finalment, en la nostra darrera línia d'investigació vàrem analitzar l'eficàcia de diferents tipus de tractament en TCA. En l'estudi 8 vàrem comparar casos totals i parcials de Bulímia nerviosa (BN), en base a trets de personalitat, simptomatologia alimentària, psicopatologia general i resposta a un tractament de caràcter psicoeducatiu. Els resultats varen indicar que els casos totals i parcials de BN, comparteixen similituds simptomatològiques, psicopatològiques i de personalitat. Així mateix, no es varen obtenir diferències respecte a la resposta del tractament entre ambdós grups de pacients. En l'estudi 9, vàrem descriure i avaluar un tractament cognitiu-conductual no centrat en els símptomes alimentaris, en una pacient cega. En aquest cas es va constatar una reducció dràstica dels símptomes alimentaris després d'aquest tipus de tractament.Fins el moment, existeixen escasses referències en la literatura que serveixin per aclarir els aspectes etiopatogènics implicats en els TCAs. Els resultats obtinguts en les nostres investigacions ajuden en el coneixement actual dels TCA i contribueixen al desenvolupament d'un nou model multimodal per la comprensió de la seva etiologia. El model que proposem combina la interacció de diversos factors (predisponents, precipitants i mantenidors). Els treballs futurs haurien de incidir en la rellevància que tenen els factors genètics, ambientals i la interacció d'ambdós, en el desenvolupament i manteniment dels TCA. És d'especial interès la qüestió de quins d'aquests factors són específics per trastorns mentals i quins ho són per TCA.