999 resultados para invariant-free


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The first finding of a Capillariid in the urinary tract of a free ranging maned wolf (Chrysocyon brachyurus) is described. The individual was an adult male attacked by dogs in the locality of Cayastacito (Santa Fe, Argentina, 31º05' S, 60º 34' W). Eggs found in urine measured 64.6-66.9µm (mean 65.4µm) x 26.9-31µm (mean 29µm). Further studies are needed to determine whether this finding corresponds to a new Capillariid species, related to C. brachyurus, or it is an already described species that has been introduced by domestic dogs.

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The increase in resting energy expenditure (REE) reported in patients with cystic fibrosis (CF) does not necessarily imply an increase in total energy expenditure (TEE). In this study REE was assessed with open-circuit indirect calorimetry, and free-living 24-hour TEE with the heart rate method. Thirteen patients with CF, aged 8 to 24 years, with adequate nutritional status and moderately decreased pulmonary function, were studied. They were compared with 13 healthy control subjects matched for gender, age, height, and nutritional status. Resting energy expenditure was higher in patients with CF (1512 +/- 88 kcal/day) than in control subjects (1339 +/- 76 kcal/day; p less than 0.01), whereas free-living 24-hour TEE (2345 +/- 127 kcal/day and 2358 +/- 256 kcal/day, respectively) and net mechanical work efficiency of walking on a treadmill (20.4 +/- 0.7% and 19.8 +/- 0.6%, respectively) were similar. Respiratory quotient was higher in patients with CF than in control subjects at rest (0.834 +/- 0.009 vs 0.797 +/- 0.008; p less than 0.05), and tended to remain so during physical exercise, indicating a higher contribution of carbohydrate oxidation to energy expenditure. We conclude that in free living conditions, patients with CF can compensate for their increase in REE by a reduction in spontaneous physical activities or other yet undefined mechanisms.

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In order to determine the frequency of therapeutic failures to chloroquine (CQ) in patients with malaria due to either Plasmodium falciparum or P. vivax, and to explore the usefulness of a malaria-free city as a sentinel site to monitor the emergence of drug resistance, 53 patients (44 infected with P. vivax and 9 with P. falciparum) were evaluated at the Laboratory of Parasitology, Universidad del Valle in Cali, Colombia. Patients received 25 mg/kg of CQ divided in three doses over 48 h; they were followed during 28 days according to WHO/PAHO protocols. While therapeutic failures to CQ in the P. vivax group were not detected, the proportion of therapeutic failures in the P. falciparum group was high (78%) and consistent with the reports from endemic areas in Colombia. The diverse origin of cases presenting therapeutic failure confirmed that P. falciparum resistant to CQ is widespread in Colombia, and further supports the change in the national antimalarial drug scheme. Monitoring of drug resistance in malaria free areas would be useful to identify sites requiring efficacy evaluation, and in some situations could be the most appropriate alternative to collect information from endemic areas where therapeutic efficacy studies are not feasible.

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CD1d tetramers loaded with alpha-galactosylceramide (alpha-GalCer) bind selectively to mouse invariant Valpha14 (Valpha14i) NKT cells and their human counterparts. Whereas tetramer binding strictly depends on the expression of a Valpha14-Jalpha18 chain in murine NKT cells, the associated beta-chain (typically expressing Vbeta8.2 or Vbeta7) appears not to influence tetramer binding. In this study, we describe novel alpha-GalCer-loaded mouse and human CD1d-IgG1 dimers, which revealed an unexpected influence of the TCR-beta chain on the avidity of CD1d:alpha-GalCer binding. A subset of Valpha14i NKT cells clearly discriminated alpha-GalCer bound to mouse or human CD1d on the basis of avidity differences conferred by the Vbeta domain of the TCR-beta chain, with Vbeta8.2 conferring higher avidity binding than Vbeta7.

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This report is the latest of four reports dealing with various aspects of smoking. There is some inevitable overlap in these reports and the actual recommendations may be somewhat different but there is a common objective of seeking the most effective measures possible to dramatically reduce the level of smoking in our society and above all to prevent our children from starting to smoke Download the Report here

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Thank you Chairman I would like to extend a warm welcome to our keynote speakers, David Byrne of the European Commission, Derek Yach from the World Health Organisation, and Paul Quinn representing Congressman Marty Meehan who sends his apologies. When we include the speakers who will address later sessions, this is, undoubtedly, one of the strongest teams that have been assembled on tobacco control in Europe. The very strength of the team underlines what I see as a shift – a very necessary shift – in the way we perceive the tobacco issue. For the last twenty years, we have lived out a paradox. It isn´t a social side issue. I make no apology for the bluntness of what I´m saying, and will come back, a little later, to the radicalism I believe we need to bring – nationally – to this issue. For starters, though, I want to lay it on the line that what we´re talking about is an epidemic as deadly as any suffered by human kind throughout the centuries. Slower than some of those epidemics in its lethal action, perhaps. But an epidemic, nonetheless. According to the World Health Organisation tobacco accounted for just over 3 million annual deaths in 1990, rising to 4.023 million annual deaths in 1998. The numbers of deaths due to tobacco will rise to 8.4 million in 2020 and reach roughly 10 million annually by 2030. This is quite simply ghastly. Tobacco kills. It kills in many different ways. It kills increasing numbers of women. It does its damage directly and indirectly. For children, much of the damage comes from smoking by adults where children live, study, play and work. The very least we should be able to offer every child is breathable air. Air that doesn´t do them damage. We´re now seeing a global public health response to the tobacco epidemic. The Tobacco Free Initiative launched by the World Health Organisation was matched by significant tobacco control initiatives throughout the world. During this conference we will hear about the experiences our speakers had in driving these initiatives. This Tobacco Free Initiative poses unique challenges to our legal frameworks at both national and international levels; in particular it raises challenges about the legal context in which tobacco products are traded and asks questions about the impact of commercial speech especially on children, and the extent of the limitations that should be imposed on it. Politicians, supported by economists and lawyers as well as the medical profession, must continue to explore and develop this context to find innovative ways to wrap public health considerations around the trade in tobacco products – very tightly. We also have the right to demand a totally new paradigm from the tobacco industry. Bluntly, the tobacco industry plays the PR game at its cynical worst. The industry sells its products without regard to the harm these products cause. At the same time, to gain social acceptance, it gives donations, endowments and patronage to high profile events and people. Not good enough. This model of behaviour is no longer acceptable in a modern society. We need one where the industry integrates social responsibility and accountability into its day-to-day activities. We have waited for this change in behaviour from the tobacco industry for many decades. Unfortunately the documents disclosed during litigation in the USA and from other sources make very depressing reading; it is clear from them that any trust society placed in the tobacco industry in the past to address the health problems associated with its products was misplaced. This industry appears to lack the necessary leadership to guide it towards just and responsible action. Instead, it chooses evasion, deception and at times illegal activity to protect its profits at any price and to avoid its responsibilities to society and its customers. It has engaged in elaborate ´spin´ to generate political tolerance, scientific uncertainty and public acceptance of its products. Legislators must act now. I see no reason why the global community should continue to wait. Effective legal controls must be laid on this errant industry. We should also keep these controls under review at regular intervals and if they are failing to achieve the desired outcomes we should be prepared to amend them. In Ireland, as Minister for Health and Children, I launched a comprehensive tobacco control policy entitled “Towards a Tobacco Free Society“. OTT?Excessive?Unrealistic? On the contrary – I believe it to be imperative and inevitable. I honestly hold that, given the range of fatal diseases caused by tobacco use we have little alternative but to pursue the clear objective of creating a tobacco free society. Aiming at a tobacco free society means ensuring public and political opinion are properly informed. It requires help to be given to smokers to break the addiction. It demands that people are protected against environmental tobacco smoke and children are protected from any inducement to experiment with this product. Over the past year we have implemented a number of measures which will support these objectives; we have established an independent Office of Tobacco Control, we have introduced free nicotine replacement therapy for low-income earners, we have extended our existing prohibitions on tobacco advertising to the print media with some minor derogations for international publications. We have raised the legal age at which a person can be sold tobacco products to eighteen years. We have invested substantially more funds in health promotion activities and we have mounted sustained information campaigns. We have engaged in sponsorship arrangements, which are new and innovative for public bodies. I have provided health boards with additional resources to let them mount a sustained inspection and enforcement service. Health boards will engage new Directors of Tobacco Control responsible for coordinating each health board´s response and for liasing with the Tobacco Control Agency I set up earlier this year. Most recently, I have published a comprehensive Bill – The Public Health (Tobacco) Bill, 2001. This Bill will, among other things, end all forms of product display and in-store advertising and will require all retailers to register with the new Tobacco Control Agency. Ten packs of cigarettes will be banned and transparent and independent testing procedures of tobacco products will be introduced. Enforcement officers will be given all the necessary powers to ensure there is full compliance with the law. On smoking in public places we will extend the existing areas covered and it is proposed that I, as Minister for Health and Children, will have the powers to introduce further prohibitions in public places such as pubs and the work place. I will also provide for the establishment of a Tobacco Free Council to advise and assist on an ongoing basis. I believe the measures already introduced and those additional ones proposed in the Bill have widespread community support. In fact, you´re going to hear a detailed presentation from the MRBI which will amply illustrate the extent of this support. The great thing is that the support comes from smokers and non-smokers alike. Bottom line, Ladies and Gentlemen, is that we are at a watershed. As a society (if you´ll allow me to play with a popular phrase) we´ve realised it´s time to ´wake up and smell the cigarettes.´ Smell them. See them for what they are. And get real about destroying their hold on our people. The MRBI survey makes it clear that the single strongest weapon we have when it comes to preventing the habit among young people is price. Simple as that. Price. Up to now, the fear of inflation has been a real impediment to increasing taxes on tobacco. It sounds a serious, logical argument. Until you take it out and look at it a little more closely. Weigh it, as it were, in two hands. I believe – and I believe this with a great passion – that we must take cigarettes out of the equation we use when awarding wage increases. I am calling on IBEC and ICTU, on employers and trade unions alike, to move away from any kind of tolerance of a trade that is killing our citizens. At one point in industrial history, cigarettes were a staple of the workingman´s life. So it was legitimate to include them in the ´basket´ of goods that goes to make up the Consumer Price Index. It isn´t legitimate to include them any more. Today, I´m saying that society collectively must take the step to remove cigarettes from the basket of normality, from the list of elements which constitute necessary consumer spending. I´m saying: “We can no longer delude ourselves. We must exclude cigarettes from the considerations we address in central wage bargaining. We must price cigarettes out of the reach of the children those cigarettes will kill.” Right now, in the monthly Central Statistics Office reports on consumer spending, the figures include cigarettes. But – right down at the bottom of the page – there´s another figure. Calculated without including cigarettes. I believe that if we continue to use the first figure as our constant measure, it will be an indictment of us as legislators, as advocates for working people, as public health professionals. If, on the other hand, we move to the use of the second figure, we will be sending out a message of startling clarity to the nation. We will be saying “We don´t count an addictive, killer drug as part of normal consumer spending.” Taking cigarettes out of the basket used to determine the Consumer Price Index will take away the inflation argument. It will not be easy, in its implications for the social partners. But it is morally inescapable. We must do it. Because it will help us stop the killer that is tobacco. If we can do it, we will give so much extra strength to health educators and the new Tobacco Control Association. This new organisation of young people who already have branches in over fifteen counties, is represented here today. The young adults who make up its membership are well placed to advise children of the dangers of tobacco addiction in a way that older generations cannot. It would strengthen their hand if cigarettes move – in price terms – out of the easy reach of our children Finally, I would like to commend so many public health advocates who have shown professional and indeed personal courage in their commitment to this critical public health issue down through the years. We need you to continue to challenge and confront this grave public health problem and to repudiate the questionable science of the tobacco industry. The Research Institute for a Tobacco Free Society represents a new and dynamic form of partnership between government and civil society. It will provide an effective platform to engage and mobilise the many different professional and academic skills necessary to guide and challenge us. I wish the conference every success.

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Navigator-gated and corrected 3D coronary MR angiography (MRA) allows submillimeter image acquisition during free breathing. However, cranial diaphragmatic drift and relative phase shifts of chest-wall motion are limiting factors for image quality and scanning duration. We hypothesized that image acquisition in the prone position would minimize artifacts related to chest-wall motion and suppress diaphragmatic drift. Twelve patients with radiographically-confirmed coronary artery disease and six healthy adult volunteers were studied in both the prone and the supine position during free-breathing navigator-gated and corrected 3D coronary MRA. Image quality and the diaphragmatic positions were objectively compared. In the prone position, there was a 36% improvement in signal-to-noise ratio (SNR; 15.5 +/- 2.7 vs. 11.4 +/- 2.6; P < 0.01) and a 34% improvement in CNR (12.5 +/- 3.3 vs. 9.3 +/- 2.5, P < 0.01). The prone position also resulted in a 17% improvement in coronary vessel definition (P < 0.01). Cranial end-expiratory diaphragmatic drift occurred less frequently in the prone position (23% +/- 17% vs. 40% +/- 26% supine; P <0.05), and navigator efficiency was higher. Prone coronary MRA results in improved SNR and CNR with enhanced coronary vessel definition. Cranial end-expiratory diaphragmatic drift also was reduced, and navigator efficiency was enhanced. When feasible, prone imaging is recommended for free-breathing coronary MRA.

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Towards a Restraint Free Environment in Nursing Homes Equality, fairness, respect, dignity, autonomy and participation are core values that underpin human rights. In residential care settings for older people we require that human rights are positively incorporated into the reality of people's lives.In 2009 the National Quality Standards for Residential Care Settings for Older People were approved. At the heart of these standards, and the regulations underpinning them, is the belief that these residential settings are peoples homes, and every possible effort must be made to ensure that the residents can live their lives to the fullest extent possible and enjoy their time there. Click here to download PDF 898KB

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The high levels of smoking in Ireland require a more concerted effort to support the continued development of a tobacco free society where people can live longer and healthier lives free from the detrimental effects of tobacco. The direction given in this policy report seeks to de-normalise tobacco within Irish society, reduce initiation rates, assist smokers to quit, protect non-smokers, especially children, from the effects of second-hand smoke, by building on a stable policy and legislative framework. These measures will be achieved within existing resources. Click here to download Tobacco Free Ireland PDF 911KB

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Summary: Detailed knowledge on tumor antigen expression and specific immune cells is required for a rational design of immunotherapy for patients with tumor invaded liver. In this study, we confirmed that Cancer/Testis (CT) tumor-associated antigens are frequently expressed in hepatocellular carcinoma (HCC) and searched for the presence of CD8+ T cells specific for these antigens. In 2/10 HLA-A2+ patients with HCC, we found that MAGE-A10 and/or SSX-2 specific CD8+ T cells naturally responded to the disease, since they were enriched in tumor lesions but not in non-tumoral liver. Isolated T cells specifically and strongly killed tumor cells in vitro, suggesting that these CTL were selected in vivo for high avidity antigen recognition, providing the rational for specific immunotherapy of HCC, based on immunization with CT antigens such as MAGE-Al 0 and SSX-2. Type 1 NKT cells express an invariant TCR α chain (Vα24.1α18, paired with Vβ11 in human) and share a specific reactivity to αGalactosylceramide (αGC) presented by CD1d. These cells can display paradoxical immuno-regulatory properties including strong anti-tumor effects upon αGC administration in murine models. To understand why NKT cells were not sufficiently protective against tumor development in patients with tumor invaded liver, we characterized the diversity of Vα24/Vβ11 NKT cells in healthy donors (HD) and cancer patients: NKT cells from HD and patients were generally diverse in terms of TCR β chain (Vβ11) variability and NKT cells from HD showed a variable recognition of αGC loaded CD 1 d multimers. Vα24/ Vβ11 NKT cells can be divided in 3 populations, the CD4, DN (CD4-/CD8-) and CD8 NKT cell subsets that show distinct ability of cytokine production. In addition, our functional analysis revealed that DN and CD8 subsets displayed a higher cytolytic potential and a weaker IFNγ release than the CD4 NKT cell subset. NKT cell subsets were variably represented in the blood of HD and cancer patients. However, HD with high NKT cell frequencies displayed an enrichment of the DN and CD8 subsets, and few of them were suggestive of an oligoclonal expansion in vivo. Comparable NKT cell frequencies were found between blood, non-tumoral liver and tumor of patients. In contrast, we identified a gradual enrichment of CD4 NKT cells from blood to the liver and to the tumor, together with a decrease of DN and CD8 NKT cell subsets. Most patient derived NKT cells were unresponsive upon αGalactosylceramide stimulation ex vivo; NKT cells from few patients displayed a weak responsiveness with different cytokine polarization. The NKT cell repertoire was thus different in tumor tissue, suggesting that CD4 NKT cells infiltrating tumors may be detrimental for protection against tumors and instead may favour the tumor growth/recurrence as recently reported in mice. Résumé en français scientifique : Afin de développer le traitement des patients porteurs d'une tumeur dans le foie par immunothérapie, de nouvelles connaissances sont requises concernant l'expression d'antigènes par les tumeurs et les cellules immunitaires spécifiques de ces antigènes. Nous avons vérifié que des antigènes associés aux tumeurs, tels que les antigènes « Cancer-Testis » (CT), sont fréquemment exprimés par le carcinome hepatocéllulaire (CHC). La recherche de lymphocytes T CD8+ spécifiques (CTL) de ces antigènes a révélé que des CTL spécifiques de MAGE-A10 et/ou SSX-2 ont répondu naturellement à la tumeur chez 2/10 patients étudiés. Ces cellules étaient présentes dans les lésions tumorales mais pas dans le foie adjacent. De plus, ces CTL ont démontré une activité cytolytique forte et spécifique contre les cellules tumorales in vitro, ce qui suggère que ces CTL ont été sélectionnés pour une haute avidité de reconnaissance de l'antigène in vivo. Ces données fournissent une base pour l'immunothérapie spécifique du CHC, en proposant de cibler les antigènes CT tels que MAGE-A10 ou SSX-2. Les cellules NKT de type 1 ont une chaîne α de TCR qui est invariante (chez l'homme, Vα24Jα18, apparié avec Vβ11) et reconnaissent spécifiquement l'αGalactosylceramide (αGC) présenté par CD1d. Ces cellules ont des propriétés immuno¬régulatrices qui peuvent être parfois contradictoires et leur activation par l'αGC induit une forte protection anti-tumorale chez la souris: Afin de comprendre pourquoi ces cellules ne sont pas assez protectrices contre le développement des tumeurs dans le foie chez l'homme, nous avons étudié la diversité des cellules NKT Vα24/Vβ11 d'individus sains (IS) et de patients cancéreux. Les cellules NKT peuvent être sous-divisées en 3 populations : Les CD4, DN (CD4- /CD8-) ou CDS, qui ont la capacité de produire des cytokines différentes. Nos analyses fonctionnelles ont aussi révélé que les sous-populations DN et CD8 ont un potentiel cytolytique plus élevé et une production d'IFNγ plus faible que la sous-population CD4. Ces sous-populations sont représentées de manière variable dans le sang des IS ou des patients. Cependant, les IS avec un taux élevé de cellules NKT ont un enrichissement des sous- populations DN ou CDS, et certains suggèrent qu'il s'agit d'une expansion oligo-clonale in vivo. Les patients avaient des fréquences comparables de cellules NKT entre le sang, le foie et la tumeur. Par contre, la sous-population CD4 était progressivement enrichie du sang vers le foie et la tumeur, tandis que les sous-populations DN ou CD8 était perdues. La plupart des cellules NKT des patients ne réagissaient pas lors de stimulation avec l'αGC ex vivo et les cellules NKT de quelques patients répondaient faiblement et avec des polarisations de cytokines différentes. Ces données suggèrent que les cellules NKT CD4, prédominantes dans les tumeurs, sont inefficaces pour la lutte anti-tumorale et pourraient même favoriser la croissance ou la récurrence tumorale. Donc, une mobilisation spécifique des cellules NKT CD4 négatives par immunothérapie pourrait favoriser l'immunité contre des tumeurs chez l'homme. Résumé en français pour un large public Au sein des globules blancs, les lymphocytes T expriment un récepteur (le TCR), qui est propre à chacun d'entre eux et leur permet d'accrocher de manière très spécifique une molécule appelée antigène. Ce TCR est employé par les lymphocytes pour inspecter les antigènes associés avec des molécules présentatrices à la surface des autres cellules. Les lymphocytes T CD8 reconnaissent un fragment de protéine (ou peptide), qui est présenté par une des molécules du Complexe Majeur d'Histocompatibilité de classe I et tuent la cellule qui présente ce peptide. Ils sont ainsi bien adaptés pour éliminer les cellules qui présentent un peptide issu d'un virus quand la cellule est infectée. D'autres cellules T CD8 reconnaissent des peptides comme les antigènes CT, qui sont produits anormalement par les cellules cancéreuses. Nous avons confirmé que les antigènes CT sont fréquemment exprimés par le cancer du foie. Nous avons également identifié des cellules T CD8 spécifiques d'antigènes CT dans la tumeur, mais pas dans le foie normal de 2 patients sur 10. Cela signifie que ces lymphocytes peuvent être naturellement activés contre la tumeur et sont capables de la trouver. De plus les lymphocytes issus d'un patient ont démontré une forte sensibilité pour reconnaître l'antigène et tuent spécifiquement les cellules tumorales. Les antigènes CT représentent donc des cibles intéressantes qui pourront être intégrés dans des vaccins thérapeutiques du cancer du foie. De cette manière, les cellules T CD8 du patient lui-même pourront être induites à détruire de manière spécifique les cellules cancéreuses. Un nouveau type de lymphocytes T a été récemment découvert: les lymphocytes NKT. Quand ils reconnaissent un glycolipide présenté par la molécule CD1d, ils sont capables, de manière encore incomprise, d'initier, d'augmenter, ou à l'inverse d'inhiber la défense immunitaire. Ces cellules NKT ont démontré qu'elles jouent un rôle important dans la défense contre les tumeurs et particulièrement dans le foie des souris. Nous avons étudié les cellules NKT de patients atteints d'une tumeur dans le foie, afin de comprendre pourquoi elles ne sont pas assez protectrice chez l'homme. Les lymphocytes NKT peuvent être sous-divisés en 3 populations: Les CD4, les DN (CD4-/CD8-) et les CD8. Ces 3 classes de NKT peuvent produire différents signaux chimiques appelés cytokines. Contrairement aux cellules NKT DN ou CDS, seules les cellules NKT CD4 sont capables de produire des cytokines qui sont défavorables pour la défense anti-tumorale. Par ailleurs nous avons trouvé que les cellules NKT CD4 tuent moins bien les cellules cancéreuses que les cellules NKT DN ou CD8. L'analyse des cellules NKT, fraîchement extraites du sang, du foie et de la tumeur de patients a révélé que les cellules NKT CD4 sont progressivement enrichies du sang vers le foie et la tumeur. La large prédominance des NKT CD4 à l'intérieur des tumeurs suggère que, chez l'homme, ces cellules sont inappropriées pour la lutte anti-tumorale. Par ailleurs, la plupart des cellules NKT de patients n'étaient pas capables de produire des cytokines après stimulation avec un antigène. Cela explique également pourquoi ces cellules ne protègent pas contre les tumeurs dans le foie.

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Rapport de synthèse : Introduction : La perfusion isolée du poumon à l'aide de Doxorubicine libre et une nouvelle forme de Doxorubicine liposomale pégylée (Liporubicine) est comparé en terme de pénétration et accumulation de Doxorubicine dans le tissu tumoral et pulmonaire dans un modèle de rats porteurs de tumeur sarcomateuse au niveau du poumon gauche. Matériel et méthode : Une tumeur sarcomateuse unique a été générée dans le poumon gauche de 39 Fischer rats, suivi 10 jours plus tard, par une perfusion isolée du poumon gauche (n =36) avec Doxorubicine libre (n=18) et Liporubicine (n=18) à une dose de 100 µg (n=9) et 400 µg (n=9) pour chaque formulation de Doxorubicine. Dans chaque poumon perfusé, la concentration de l'agent cytostatique et sa distribution ont été investiguées dans la tumeur et trois parties du poumon normal par HLPC (n=6) et par microscopie de florescence (n=3). Des analyses histologiques et inmunohistochimiques (facteur von Willebrand) ont été effectuées sur trois animaux non traités. Résultats : Les tumeurs sarcomateuses dans les animaux de contrôle démontraient une bonne vascularisation avec de fines branches capillaires qui étaient présentes partout dans les tumeurs. La perfusion isolée du poumon démontrait une distribution de l'agent cytostatique d'une manière hétérogène dans le poumon perfusé et une concentration de Doxorubicine inférieure dans les tumeurs par rapport au tissu pulmonaire sein pour les deux formulations de Doxorubicine et les deux doses appliquées. La perfusion isolée du poumon avec Doxorubicine libre démontrait une concentration significativement plus élevée que Liporubicine dans la tumeur et le parenchyme pulmonaire pour les deux doses appliquées (p < 0,01). Néanmoins, le coefficient de concentration tumorale et pulmonaire était plus bas pour Doxorubicine libre que pour Liporubicine pour une dose de 100 µg (0.27 ± 0.1 vs 0.53 ± 0.5, p=0.23) tandis qu'il était similaire pour les deux formulations de Doxorubicine à une dose de 400 µg (0.67 ± 0.2 vs 0.54 ± 0.2, p=0.34). Les deux formulations de Doxorubicine émergeaient un signal de fluorescence provenant de tous les compartiments du parenchyme pulmonaire mais seulement un signal sporadique et faible émergeant des tumeurs, provenant de la périphérie de la tumeur et des vaisseaux situés à l'intérieur de la tumeur, pour les deux doses appliquées. Conclusion : La perfusion isolée du poumon démontrait une distribution hétérogène de la Doxorubicine et sa forme liposomale dans le poumon perfusé et une accumulation plus faible dans la tumeur que dans le tissu parenchymateux adjacent pour les deux formulations de Doxorubicine et les deux doses appliquées.

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BACKGROUND: Plasma free and urinary metanephrines are recognized biomarkers for the assessment of pheochromocytoma. Plasma total metanephrines with a long half-life may represent another useful biomarker. OBJECTIVE: The aim of this study is to evaluate the diagnostic performances of plasma total metanephrines alone or combined with free metanephrines and fractionated 24-h urinary metanephrines. METHODS: A retrospective, case-control diagnostic test study was conducted between 1999 and 2007 in two university hospitals in Switzerland and two institutions in France. The patients included 46 cases with histologically proven pheochromocytoma, and 181 controls suspected of tumor with negative investigations and 3-year follow-up. None had renal dysfunction. Sensitivity and specificity were compared after expressing each measurement result as a ratio over its upper reference limit, adding the ratios of normetanephrine and metanephrine, and defining cut-off values of 1 or 2 for this sum. RESULTS: Applying a cut-off value of 1, plasma free and total metanephrines and urinary fractionated metanephrines had similar sensitivities of 96% (95% confidence interval, 86-99%), 95% (85-99%), and 95% (84-99%) along with similar specificities of 89% (83-94%), 91% (84-95%), and 86% (80-91%). A cut-off of 2 for the sum of ratios over reference limit improves the specificity, and it can be used for a confirmation test based on another biomarker taken among the three biomarkers. CONCLUSION: All three metanephrine-based tests perform equivalently for diagnosing pheochromocytoma in the absence of renal insufficiency, and can be conveniently associated two by two for confirming/excluding tumor.