949 resultados para Legal Environment of Distribution,


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The neonatal immune response is impaired during the first weeks after birth. To obtain a better understanding of this immaturity, we investigated the development of T cell interactions with B cells in mice. For this purpose, we analyzed the immune response to three T-dependent antigens in vivo: (i) the polyclonal antibody response induced by vaccinia virus; (ii) the production of polyclonal and specific antibodies following immunization with hapten-carrier conjugates; (iii) the mouse mammary tumor virus superantigen (sAg) response involving an increase in sAg-reactive T cells and induction of polyclonal antibody production. After vaccinia virus injection into neonates, the polyclonal antibody response was similar to that observed in adult mice. The antibody response to hapten-carrier conjugates, however, was delayed and reduced. Injection with sAg-expressing B cells from neonatal or adult mice allowed us to determine whether B cells, T cells or both were implicated in the reduced immune response. In these sAg responses, neonatal T cells were stimulated by both neonatal and adult sAg-presenting B cells but only B cells from adult mice differentiated into IgM- and IgG-secreting plasma cells in the neonatal environment in vivo. Injecting neonatal B cells into adult mice did not induce antibody production. These results demonstrate that the environment of the neonatal lymph node is able to support a T and B cell response, and that immaturity of B cells plays a key role in the reduced immune response observed in the neonate.

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The prescription, widely discussed and defined conceptually in recent years in an environment of widening the spectrum of responsibilities nurse, has capacity for integration and definition in the area of accident and emergency care and carried out over the patient urgently, about emergencies and life-long commitment. Be necessary to frame throughout the legal framework, following the amendment of the Twelfth Additional Provision of Law 29/2006 of guarantees and rational use of drugs and medical devices, can be waived and implementation required, provided under model and through the nursing process and method and as an exponent and endorsementn of science and advanced clinical practice, to join the idea of interdisciplinary professional consensus that the law posed by the preparation and implementation of standardized protocols, algorithms and / or clinical practice guidelines in the context of what has come to be called "collaborative standard prescription": Prescription to the nurse in certain clinical situations in terms of a performance protocol, agreed with multidisciplinary team care health of the population (Group Protocols), which can be considered an intermediate step in the evolution towards independent nurse prescribing, providing nurses experience of a prescription under these protocols and demonstrating their capabilities.

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RESUME En Amérique Centrale et en Amérique du Sud, la leishmaniose cutanéo-muqueuse (LCM) est provoquée par le protozoaire Leishmania du sous-genre Viannia dont font partie L. (V.) braziliensis, L. (V.) panamensis et L. (V.) guyanensis. Dans la LCM, après guérison apparente de la lésion primitive, des lésions secondaires peuvent apparaître dues à la migration de l'infection à partir du site d'inoculation vers les muqueuses de l'ororhino-pharynx. Ce type de dissémination, communément appelé métastase, peut se produire plusieurs années après la guérison de la lésion cutanée initiale, et est un facteur majeur contribuant à la morbidité associée à la LCM. L'expression reproductible de l'activité métastatique au sein de populations discrètes de leishmanies chez le hamster fournit un modèle expérimental permettant d'étudier le degré de virulence du parasite. Nous avons utilisé des clones de L. (V.) guyanensis présentant des phénotypes stables allant d'un caractère hautement métastatique (M+) à non-métastatique (M-) comme outils pour mettre en évidence des facteurs spécifiques liés à la métastase chez les leishmanies du Nouveau Monde. Des analyses protéomiques comparatives utilisant l'électrophorèse bidimensionnelle sur gel de polyacrylamide couplée à de la spectrométrie de masse ont permis l'identification de plusieurs formes de la tryparedoxine peroxidase (TXNPx) en tant que polypeptides associés au phénotype métastatique. TXNPx, une enzyme de la famille des peroxiredoxines (Prxs), protéines antioxydantes, fonctionne comme la dernière peroxydase d'une cascade d'oxydoréductases qui réduit le peroxyde d'hydrogène aux dépens de NADPH. Toutes les Prxs sont caractérisées par un (1-Cys Prx) ou par deux résidus cystéines (2-Cys Prx), respectivement placés dans un environnement structurel conservé de la protéine et sont centrales dans la réaction catalytique. Des immuno-empreintes (« immunoblotting ») ont révélé que TXNPx est présente sous forme dimérique dans les promastigotes (M+) alors que dans les promastigotes, (M-) TXNPx est présente sous forme monomérique et dimérique. Cette caractéristique spécifique de dimérisation pourrait expliquer les différentes activités enzymatiques observées entre les deux promastigotes (M+) et (M-) en présence de peroxyde d'hydrogène ainsi que leur différence de survie et de charge parasitaire à l'intérieur des macrophages. Par conséquent, le processus métastatique pourrait être lié à la capacité du parasite à échapper efficacement aux défenses microbicides de la cellule hôte. ABSTRACT In South and Central America, protozoan parasites of the Leishmania Viannia subgenus including L. (V.) braziliensis, L. (V.) guyanensis and L. (V). panamensis cause mucocutaneous leishmaniasis (MCL). In MCL, after apparent cure of the primary lesion, secondary lesions may appear in the nasopharyngeal tissues of the infected host due to dissemination of the infection from the inoculation site. This type of dissemination, known as metastasis, can occur several years after healing of the original cutaneous lesion, and is a major contributory factor to the morbidity associated with MCL. The reproducible expression of metastasis by discrete populations of Leishmania parasites in hamsters provides an experimental model to examine the expression of parasite virulence. We used laboratory clones of L. (V.) guyanensis with stable phenotypes ranging from highly metastatic (M+) to non-metastatic (M-) as tools for the discovery of specific factors associated with metastasis in New World Leishmania species. Comparative proteome analyses via 2D-electrophoresis (2-DE) coupled with mass spectrometry (MS) enabled the identification of various isoforms of tryparedoxin peroxidase (TXNPx) as polypeptides associated with the metastatic phenotype. TXNPx, an enzyme related to the antioxidant peroxiredoxin family (Prx) functions as the terminal peroxidase of a redox cascade that reduces hydroperoxides by NADPH. All Prxs are characterized by one (1-Cys Prx) or two cysteine residue(s) (2-Cys Prx), respectively, located in a conserved structural environment of the protein which are central for the catalytic reaction. Immunoblotting analysis revealed that, under non-reducing denaturing conditions, TXNPx is present in dimeric forms in (M+) promastigotes, whereas in (M-) promastigotes, both monomeric and dimeric forms are found. This specific dimerization feature may explain the different enzymatic activities of both (M+) and (M-) promastigote parasites in the presence of H2O2 and their difference in survival and parasite load inside macrophages. Therefore, the metastatic process could be related to the ability of the parasite to efficiently evade the microbicidal effect of the host cell.

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Leukocyte Elastase Inhibitor (LEI, also called serpin B1) is a protein involved in apoptosis among other physiological processes. We have previously shown that upon cleavage by its cognate protease, LEI is transformed into L-DNase II, a protein with a pro-apoptotic activity. The caspase independent apoptotic pathway, in which L-DNase II is the final effector, interacts with other pro-apoptotic molecules like Poly-ADP-Ribose polymerase (PARP) or Apoptosis Inducing Factor (AIF). The screening of LEI/L-DNase II interactions showed a possible interaction with several members of the BCL-2 family of proteins which are known to have a central role in the regulation of caspase dependent cell death. In this study, we investigated the regulation of LEI/L-DNase II pathway by two members of this family of proteins: BAX and BCL-2, which have opposite effects on cell survival. We show that, in both BHK and HeLa cells, LEI/L-DNase II can interact with BCL-2 and BAX in apoptotic and non-apoptotic conditions. These proteins which are usually thought to be anti-apoptotic and pro-apoptotic respectively, both inhibit the L-DNase II pro-apoptotic activity. These results give further insight in the regulation of caspase-independent pathways and highlight the involvement of the intracellular environment of a given protein in the determinism of its function. They also add a link between caspase-dependent and independent pathways of apoptosis.

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AIM: This study aims to investigate the clinical and demographic factors influencing gentamicin pharmacokinetics in a large cohort of unselected premature and term newborns and to evaluate optimal regimens in this population. METHODS: All gentamicin concentration data, along with clinical and demographic characteristics, were retrieved from medical charts in a Neonatal Intensive Care Unit over 5 years within the frame of a routine therapeutic drug monitoring programme. Data were described using non-linear mixed-effects regression analysis ( nonmem®). RESULTS: A total of 3039 gentamicin concentrations collected in 994 preterm and 455 term newborns were included in the analysis. A two compartment model best characterized gentamicin disposition. The average parameter estimates, for a median body weight of 2170 g, were clearance (CL) 0.089 l h(-1) (CV 28%), central volume of distribution (Vc ) 0.908 l (CV 18%), intercompartmental clearance (Q) 0.157 l h(-1) and peripheral volume of distribution (Vp ) 0.560 l. Body weight, gestational age and post-natal age positively influenced CL. Dopamine co-administration had a significant negative effect on CL, whereas the influence of indomethacin and furosemide was not significant. Both body weight and gestational age significantly influenced Vc . Model-based simulations confirmed that, compared with term neonates, preterm infants need higher doses, superior to 4 mg kg(-1) , at extended intervals to achieve adequate concentrations. CONCLUSIONS: This observational study conducted in a large cohort of newborns confirms the importance of body weight and gestational age for dosage adjustment. The model will serve to set up dosing recommendations and elaborate a Bayesian tool for dosage individualization based on concentration monitoring.

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Six patients, five of whom had normal and one impaired renal function, and all suffering from purulent arthritis caused by cephalosporin-sensitive germs, were given a seven-day course of 8 g cephacetrile daily. On the first day, 6 g were administered by continuous intravenous infusion at the rate of 500 mg/h, followed by 2 g over a further 45 min. On days 2 to 7, the patients received 2 short infusions of 4 g each at an interval of 12 h. In four patients with normal renal function, serum half-life ranged from 0.8 to 1.4 h, serum levels during continuous infusion from 19 to 31 microgram/ml, and total clearances from 265 to 434 ml/min. In one patients, these values were 1.6 h, 70 microgram/ml and 131 ml/min respectively (small volume of distribution). The concentrations in the synovial fluid varied from 2 to 29 mcirogram/ml; they were generally lower than the serum levels, but clearly exceeded the minimum inhibitory concentrations for germs commonly present in purulent arthritis. In five patients, the synovial fluid became germ-free and the arthritis was clinically cured. In the case presenting with renal insufficiency, the serum half-life was 5.8 h. During continuous administration, a steady state was not attained; peak serum levels amo9nted to 75 microgram/ml and the total clearance to 61 ml/min. The cephacetrile concentrations in the synovial fluid were very high (26 and 67 microgram/ml). In this case, in which the renal insufficiency associated with mycosis fungoides was present before the treatment, renal function deteriorated futher during treatment while the arthritis improved.

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The main objective of this perspective paper is to analyze the role of the judiciary in resolving conflicts between cattle raisers and meatpacking firms in Brazil. Looking at the transaction for the acquisition of cattle for slaughter in the state of Mato Grosso do Sul (the central-western region of Brazil), the analysis encompasses three steps. First, the authors describe the transaction pattern between cattle raisers and meatpacking firms, identifying a guarantee vacuum within the supply chain. Secondly, the authors present evidence that the guarantee vacuum may give rise to legal conflicts of non-payment, which are indeed prevalent in disputes that reach the courts. Finally, the role of the judiciary in resolving these conflicts is investigated. Results suggest that, on average, producers have little confidence in the legal system, indicating the potential function that informal mechanisms may play in the supply chain. The paper concludes by suggesting some implications for public and private strategies.

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BACKGROUND: Relatively little is known about the current health care situation and the legal rights of ageing prisoners worldwide. To date, only a few studies have investigated their rights to health care. However, elderly prisoners need special attention. OBJECTIVE: The aim of this article is to critically review the health care situation of older prisoners by analysing the relevant national and international legal frameworks with a particular focus on Switzerland, England and Wales, and the United States (U.S.). METHODS: Publications on legal frameworks were searched using Web of Science, PubMed, MEDLINE, HeinOnline, and the National Criminal Justice Reference Service. Searches utilizing combinations of keywords relating to ageing prisoners were performed. Relevant reports and policy documents were obtained in order to understand the legal settings in Switzerland, England and Wales, and the U.S. All articles, reports, and policy documents published in English and German between 1774 to June 2012 were included for analysis. Using a comparative approach, an outline was completed to distinguish positive policies in this area. Regulatory approaches were investigated through evaluations of soft laws applicable in Europe and U.S. Supreme Court judgements. RESULTS: Even though several documents could be interpreted as guaranteeing adequate health care for ageing prisoners, there is no specific regulation that addresses this issue completely. The Vienna International Plan of Action on Ageing contributes the most by providing an in-depth analysis of the health care needs of older persons. Still, critical analysis of retrieved documents reveals the lack of specific legislation regarding the health care for ageing prisoners. CONCLUSION: No consistent regulation delineates the provision of health care for ageing prisoners. Neither national nor international institutions have enforceable laws that secure the precarious situation of older adults in prisons. To initiate a change, this work presents critical issues that must be addressed to protect the right to health care and well-being of ageing prisoners. Additionally, it is important to design legal structures and guidelines which acknowledge and accommodate the needs of ageing prisoners.

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RésuméL'origine de l'obésité, qui atteint des proportions épidémiques, est complexe. Elle est liée au mode de vie et au comportement des individus par rapport à l'activité physique, expression des choix individuels et de l'interaction avec l'environnement. Les mesures du comportement au niveau de l'activité physique des individus face à leur environnement, la répartition des types d'activité physique, la durée, la fréquence, l'intensité, et la dépense énergétique sont d'une grande importance. Aujourd'hui, il y a un manque de méthodes permettant une évaluation précise et objective de l'activité physique et du comportement des individus. Afin de compléter les recherches relatives à l'activité physique, à l'obésité et à certaines maladies, le premier objectif du travail de thèse était de développer un modèle pour l'identification objective des types d'activité physique dans des conditions de vie réelles et l'estimation de la dépense énergétique basée sur une combinaison de 2 accéléromètres et 1 GPS. Le modèle prend en compte qu'une activité donnée peut être accomplie de différentes façons dans la vie réelle. Les activités quotidiennes ont pu être classées en 8 catégories, de sédentaires à actives, avec une précision de 1 min. La dépense énergétique a pu peut être prédite avec précision par le modèle. Après validation du modèle, le comportement des individus de l'activité physique a été évalué dans une seconde étude. Nous avons émis l'hypothèse que, dans un environnement caractérisé par les pentes, les personnes obèses sont tentées d'éviter les pentes raides et de diminuer la vitesse de marche au cours d'une activité physique spontanée, ainsi que pendant les exercices prescrits et structurés. Nous avons donc caractérisé, par moyen du modèle développé, le comportement des individus obèses dans un environnement vallonné urbain. La façon dont on aborde un environnement valloné dans les déplacements quotidiens devrait également être considérée lors de la prescription de marche supplémentaire afin d'augmenter l'activité physique.SummaryOrigin of obesity, that reached epidemic proportion, is complex and may be linked to different lifestyle and physical activity behaviour. Measurement of physical activity behaviour of individuals towards their environment, the distribution of physical activity in terms of physical activity type, volume, duration, frequency, intensity, and energy expenditure is of great importance. Nowadays, there is a lack of methods for accurate and objective assessment of physical activity and of individuals' physical activity behaviour. In order to complement the research relating physical activity to obesity and related diseases, the first aim of the thesis work was to develop a model for objective identification of physical activity types in real-life condition and energy expenditure based on a combination of 2 accelerometers and 1 GPS device. The model takes into account that a given activity can be achieved in many different ways in real life condition. Daily activities could be classified in 8 categories, as sedentary to active physical activity, within 1 min accuracy, and physical activity patterns determined. The energy expenditure could be predicted accurately with an accuracy below 10%. Furthermore, individuals' physical activity behaviour is expression of individual choices and their interaction with the neighbourhood environment. In a second study, we hypothesized that, in an environment characterized by inclines, obese individuals are tempted to avoid steep positive slopes and to decrease walking speed during spontaneous outdoor physical activity, as well as during prescribed structured bouts of exercise. Finally, we characterized, by mean of the developed model, the physical activity behaviour of obese individuals in a hilly urban environment. Quantifying how one tackles hilly environment or avoids slope in their everyday displacements should be also considered while prescribing extra walking in free-living conditions in order to increase physical activity.

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Methadone is widely used for the treatment of opioid dependence. Although in most countries the drug is administered as a racemic mixture of (R)- and (S)- methadone, (R)-methadone accounts for most, if not all, of the opioid effects. Methadone can be detected in the blood 15-45 minutes after oral administration, with peak plasma concentration at 2.5-4 hours. Methadone has a mean bioavailability of around 75% (range 36-100%). Methadone is highly bound to plasma proteins, in particular to alpha(1)-acid glycoprotein. Its mean free fraction is around 13%, with a 4-fold interindividual variation. Its volume of distribution is about 4 L/kg (range 2-13 L/kg). The elimination of methadone is mediated by biotransformation, followed by renal and faecal excretion. Total body clearance is about 0.095 L/min, with wide interindividual variation (range 0.02-2 L/min). Plasma concentrations of methadone decrease in a biexponential manner, with a mean value of around 22 hours (range 5-130 hours) for elimination half-life. For the active (R)-enantiomer, mean values of around 40 hours have been determined. Cytochrome P450 (CYP) 3A4 and to a lesser extent 2D6 are probably the main isoforms involved in methadone metabolism. Rifampicin (rifampin), phenobarbital, phenytoin, carbamazepine, nevirapine, and efavirenz decrease methadone blood concentrations, probably by induction of CYP3A4 activity, which can result in severe withdrawal symptoms. Inhibitors of CYP3A4, such as fluconazole, and of CYP2D6, such as paroxetine, increase methadone blood concentrations. There is an up to 17-fold interindividual variation of methadone blood concentration for a given dosage, and interindividual variability of CYP enzymes accounts for a large part of this variation. Since methadone probably also displays large interindividual variability in its pharmacodynamics, methadone treatment must be individually adapted to each patient. Because of the high morbidity and mortality associated with opioid dependence, it is of major importance that methadone is used at an effective dosage in maintenance treatment: at least 60 mg/day, but typically 80-100 mg/day. Recent studies also show that a subset of patients might benefit from methadone dosages larger than 100 mg/day, many of them because of high clearance. In clinical management, medical evaluation of objective signs and subjective symptoms is sufficient for dosage titration in most patients. However, therapeutic drug monitoring can be useful in particular situations. In the case of non-response trough plasma concentrations of 400 microg/L for (R,S)-methadone or 250 microg/L for (R)-methadone might be used as target values.

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RESUME : Objectif: Le glioblastome multiforme (GBM) est la tumeur cérébrale maligne la plus agressive qui conduit au décès de la majorité des patients moins d'une année après le diagnostic. La plupart des agents chimiothérapeutiques actuellement disponibles ne traversent pas la barrière hémato¬encéphalique et ne peuvent par conséquent pas être utilisés pour ce type de tumeur. Le Temozolomide (TMZ) est un nouvel agent alkylant récemment développé pour le traitement des gliomes malins. A ce jour, très peu d'informations sont disponibles sur la pénétration intra-cérébrale de cet agent. Au cours d'une étude pilote de phase II menée auprès de 64 patients atteints de GBM, l'administration précoce de TMZ combinée à une radiothérapie standard (RT) afin d'intervenir au plus tôt dans l'évolution de la maladie, a permis de prolonger la survie de ces patients, résultat qui pu être confirmé par la suite lors de l'étude randomisée de phase III. L'objectif de cette étude a été de déterminer les paramètres pharmacocinétique du TMZ dans le plasma et le liquide céphalo-rachidien (LCR), d'évaluer l'influence de certains facteurs individuels (âge, sexe, surface corporelle, fonction rénale/hépatique, co-médications, RT concomitante) sur ces différents paramètres, et enfin d'explorer la relation existant entre l'exposition au TMZ et certains marqueurs cliniques d'efficacité et de toxicité. Matériel et Méthode: Les concentrations de TMZ ont été mesurées par chromatographie liquide à haute performance (HPLC) dans le plasma et le LCR de 35 patients atteints de GBM nouvellement diagnostiqués (étude pilote) ou de gliomes malins en récidive (étude récidive). L'analyse pharmacocinétique de population a été réalisée à l'aide du programme NONMEM. L'exposition systémique et cérébrale, définie par les AUC (Area Under the time-concentration Curve) dans le plasma et le LCR, a été estimée pour chaque patient et corrélée à la toxicité, la survie ainsi que la survie sans progression tumorale. Résultats: Un modèle à 1 compartiment avec une cinétique d'absorption et de transfert Kplasma -> LCR de ordre a été retenu afin de décrire le profil pharmacocinétique du TMZ. Les valeurs moyennes de population ont été de 10 L/h pour la clairance, de 30.3 L pour le volume de distribution, de 2.1 h pour la 1/2 vie d'élimination, de 5.78 hE-1 pour la constante d'absorption, de 7.2 10E4 hE-1 pour Kplasma->LCR et de 0.76 hE-1 pour KLCR plasma. La surface corporelle a montré une influence significative sur la clairance et le volume de distribution, alors que le sexe influence la clairance uniquement. L'AUC mesurée dans le LCR représente ~20% de celle du plasma et une augmentation de 15% de Kplasma->LCR a été observée lors du traitement concomitant de radiochimiothérapie. Conclusions: Cette étude est la première analyse pharmacocinétique effectuée chez l'homme permettant de quantifier la pénétration intra-cérébrale du TMZ. Le rapport AUC LCR/AUC Plasma a été de 20%. Le degré d'exposition systémique et cérébral au TMZ ne semble pas être un meilleur facteur prédictif de la survie ou de la tolérance au produit que ne l'est la dose cumulée seule. ABSTRACT Purpose: Scarce information is available on the brain penetration of temozolomide (TMZ), although this novel methylating agent is mainly used for the treatment of ma¬lignant brain tumors. The purpose was to assess TNIZ phar¬macokinetics in plasma and cerebrospinal fluid (CSF) along with its inter-individual variability, to characterize covari¬ates and to explore relationships between systemic or cere¬bral drug exposure and clinical outcomes. Experimental Design: TMZ levels were measured by high-performance liquid chromatography in plasma and CSF samples from 35 patients with newly diagnosed or recurrent malignant gliomas. The population pharmacoki¬netic analysis was performed with nonlinear mixed-effect modeling software. Drug exposure, defined by the area un¬der the concentration-time curve (AUC) in plasma and CSF, was estimated for each patient and correlated with toxicity, survival, and progression-free survival. Results: A three-compartment model with first-order absorption and transfer rates between plasma and CSF described the data appropriately. Oral clearance was 10 liter/h; volume of distribution (VD), 30.3 liters; absorption constant rate, 5.8 hE-1; elimination half-time, 2.1 h; transfer rate from plasma to CSF (Kplasma->CSF), 7.2 x 10E-4hE-1 and the backwards rate, 0.76hE-1. Body surface area signifi¬cantly influenced both clearance and VD, and clearance was sex dependent. The AU CSF corresponded to 20% of the AUCplasma. A trend toward an increased K plasma->CSF of 15% was observed in case of concomitant radiochemo-therapy. No significant correlations between AUC in plasma or CSF and toxicity, survival, or progression-free survival were apparent after deduction of dose-effect. Conclusions: This is the first human pharmacokinetic study on TMZ to quantify CSF penetration. The AUC CSF/ AUC plasma ratio was 20%. Systemic or cerebral exposures are not better predictors than the cumulative dose alone for both efficacy and safety.

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The excessive accumulation of the adipose tissue is at the origin of the obesity. However its severity has no direct correlation with the comorbidities. These last ones are rather linked to the type of distribution of the fat than to its total quantity. The morphological and functional analysis of the adipose tissue reveals specific differences in its localization. The adipose tissue is thus a complex organ constituted by several cell types having various capacities of hypertrophy, hyperplasia and differentiation. While the first one is more predominant in the subcutaneous compartment, where the cell size is big, the others are more specific of the visceral adipocytes. Finally the severity of the obesity is linked to hypertrophy, while the comorbidities are associated with the capacity of proliferation and differentiation.

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Germination experiments were performed with seeds of two species of genus Allium section Allium, a rare and endangered species A. pyrenaicum and a common A. sphaerocephalon. Different pre-treatments and a photoperiod of 24 h darkness were applied in order to simulate different germination conditions. Both species showed a high percentage of viable seeds a part of which were dormant. An elevate percentage of dormant seeds could be caused by a later collection time. Low altitude populations had more mortality than the others, possibly caused by the hard summer conditions during flowering and fruiting time. Comparisons between dates of species coexistence localities only show inter-population variability and it could be caused by the detected dormancy. Darkness accelerates germination, possibly for elongation radicle stimulation. Heat-shock pre-treatments decreased germination time in seeds from localities where fire is a probable event. The rarity of A. Pyrenaicum not seems to be caused by restricted germination requirements but is attributable to distinct habitat preferences, related to his altitudinal range of distribution

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AIMS: The aims of this observational study were to assess the variability in imatinib pharmacokinetics and to explore the relationship between its disposition and various biological covariates, especially plasma alpha1-acid glycoprotein concentrations. METHODS: A population pharmacokinetic analysis was performed using NONMEM based on 321 plasma samples from 59 patients with either chronic myeloid leukaemia or gastrointestinal stromal tumours. The influence of covariates on oral clearance and volume of distribution was examined. Furthermore, the in vivo intracellular pharmacokinetics of imatinib was explored in five patients. RESULTS: A one-compartment model with first-order absorption appropriately described the data, giving a mean (+/-SEM) oral clearance of 14.3 l h-1 (+/-1.0) and a volume of distribution of 347 l (+/-62). Oral clearance was influenced by body weight, age, sex and disease diagnosis. A large proportion of the interindividual variability (36% of clearance and 63% of volume of distribution) remained unexplained by these demographic covariates. Plasma alpha1-acid glycoprotein concentrations had a marked influence on total imatinib concentrations. Moreover, we observed an intra/extracellular ratio of 8, suggesting substantial uptake of the drug into the target cells. CONCLUSION: Because of the high pharmacokinetic variability of imatinib and the reported relationships between its plasma concentration and efficacy and toxicity, the usefulness of therapeutic drug monitoring as an aid to optimizing therapy should be further investigated. Ideally, such an approach should take account of either circulating alpha1-acid glycoprotein concentrations or free imatinib concentrations.

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Recommendations and laws do not always contain specific and clear provisions on the use of cadaveric material in research, and even more rarely do they address explicitly the ethical issues related to research on material obtained during forensic autopsy. In this article we analyse existing legal frameworks in Europe by comparing the legal provisions in 2 European Countries which are member states of the Council of Europe, the UK and Switzerland. They were chosen because they have distinct legal frameworks that make comparisons interesting. In addition, the detailed laws of the UK and a specific law project and national ethical recommendations in Switzerland permit us to define more clearly the legal range of options for researchers using cadaveric material obtained during forensic investigations. The Human Tissue Act 2004 in England, Wales and Northern Ireland, its Scottish equivalent with the same title (2006) and the national ethical guidelines in Switzerland all require consent from the deceased person, an appropriate relative or a person with power of attorney for healthcare decisions before cadaveric biological material can be obtained and used for research. However, if the purpose of the autopsy is purely forensic, no such authorization will be sought to carry out the autopsy and related analyses, which might include genetic testing. In order to be allowed to carry out future research projects, families need to be approached for informed consent, unless the deceased person had left written directives including permission to use his or her tissues for research.