369 resultados para Chambres basses


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In February 2007, sweet orange trees with characteristic symptoms of huanglongbing (HLB) were encountered in a region of Sao Paulo state (SPs) hitherto free of HLB. These trees tested negative for the three liberibacter species associated with HLB. A polymerase chain reaction (PCR) product from symptomatic fruit columella DNA amplifications with universal primers fDI/rPI was cloned and sequenced. The corresponding agent was found to have highest 16S rDNA sequence identity (99%) with the Pigeon pea witches`-broom phytoplasma of group 16Sr IX. Sequences of PCR products obtained with phytoplasma 16S rDNA primer pairs fU5/rU3, fU5/P7 confirm these result.,;. With two primers D7f2/D7r2 designed based oil the 16S rDNA Sequence of the cloned DNA fragment, positive amplifications were obtained from more than one hundred samples including symptomatic fruits and blotchy mottle leaves. Samples positive for phytoplasmas were negative for liberibacters, except for four samples, which were positive for both the phytoplasma and `Candidatus Liberibacter asiaticus`. The phytoplasma was detected by electron microscopy in the sieve tubes of midribs from symptomatic leaves. These results Show that a phytoplasma of group IX is associated with citrus HLB symptoms ill northern, central, and Southern SPs. This phytoplasma has very probably been transmitted to citrus from an external Source of inoculum, but the Putative insect vector is not yet known.

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RESUMO: Objectivos 1. Avaliar a morbilidade urinária e sexual secundária à braquiterapia prostática com implante de I125. 2. Avaliar a influência da hormonoterapia neoadjuvante e adjuvante na morbilidade urinária e sexual secundária à braquiterapia(I125). 3. Avaliar a influência da associação da radioterapia externa na morbilidade urinária e sexual secundária à braquiterapia(I125). 4. Avaliar a morbilidade urinária dos doentes com contra-indicação relativa (próstatas volumosas, IPSS elevado).Material e métodos De Setembro de 2000 a Dezembro de 2004 foram recrutados 204 doentes com o diagnóstico de carcinoma da próstata localizado (T1 e T2) ou localmente avançado (T3) e expectativa de vida superior a 10 anos. Foram submetidos a braquiterapia, com implante transperineal de Iodo 125 (I125) em monoterapia ou combinada com hormonoterapia e/ou radioterapia externa (tratamento trimodal). Definiram-se diversos sub-grupos de pacientes, consoante algumas características habitualmente referidas como factores de risco para a morbilidade do tratamento de braquiterapia prostática, com o objectivo de analisar a sua influência sobre a morbilidade urinária e sexual: Grupo 1: Braquiterapia em monoterapia (MONO) versus braquiterapia associada a radioterapia externa (BCOMB) Grupo 2: Próstatas volumosas (>50ml) versus próstatas não volumosas (<50ml)Grupo 3: Braquiterapia associada a hormonoterapia (HORM) versus braquiterapia sem hormonoterapia (NHORM)Grupo 4: IPSS elevado versus IPSS baixo Avaliou-se a evolução do IPSS, QoL, taxa de RTU-P e retenção urinária pós implante, e evolução do BSFI durante todo o período de seguimento. Resultados Grupo 1: Para o grupo MONO o IPSS iniciou-se com 7.1, sofreu agravamento para 16.1 e 15.9 ao primeiro e terceiro meses. Aos 12 meses, o IPSS desceu para 10.1 enquanto que, aos 18 e 24 meses, o IPSS foi de 7.3 e 5.8. O grupo BCOMB iniciou com IPSS de 9.4. Sofreu agravamento ligeiro e pouco acentuado até aos 6 meses (IPSS de 14). A evolução do IPSS foi, então, flutuante com IPSS de 5.9 aos 12 meses e 9.5 aos 18 meses. Aos 24 meses apresentava IPSS de 6.7. A taxa de retenção urinária (6.4% e 0%) e de RTU-P (2.0% e 0%) foram semelhantes nos grupos MONO e BCOMB, respectivamente (p=0.375 e p=1). A evolução da qualidade das erecções foi semelhante nos dois grupos excepto aos 6 meses em que MONO apresentou o valor 6 e BCOMB 3.7 (p=0.029). A percentagem de doentes potentes foi significativamente inferior nos primeiros 6 meses após a braquiterapia para o grupo BCOMB relativamente ao grupo MONO: 36%–74%; 33%–73%; 33%–75%. Após os 6 meses os grupos foram homogéneos. Grupo 2: O IPSS evoluiu nas próstatas <50ml e >50ml de 7–9 para 15-19 ao primeiro mês e 15-18 ao 3.º mês. Apenas ao primeiro mês é que as diferenças no IPSS foram significativas (p=0.061). Após o 3.º mês os dois grupos foram semelhantes: IPSS de 8 e 12 ao 12.º mês e 5.7 e 6 ao 24.º mês. As taxas de retenção urinária e de RTU-P foram semelhantes (p=0.054 e p=0.286) Grupo 3: A evolução do IPSS, taxas de retenção urinária e de RTU-P foram sobreponíveis em ambos os grupos. A evolução da líbido, erecções, percentagem de doentes potentes, ejaculação, incómodo e satisfação foi significativamente inferior no grupo HORM relativamente ao grupo N HORM apenas ao primeiro mês (valores de p<0.0001; <0.0001; < 0.0001; 0.009 e 0.002 respectivamente) Grupo 4: A evolução do IPSS nos doentes com IPSS elevado foi a seguinte: 22.17(0M); 19.5(1M); 20.5(3M); 15.3(6M); 15.7(12M); 11(18M); 8(24M) A evolução do IPSS nos doentes com IPSS baixo foi a seguinte: 5.9(0M); 15.3(1M); 14.9(3M); 12.2(6M); 8.9(12M); 7.2(18M), 5.5(24M) As taxas de RTU-P (2.8% e 0%) e retenção urinária (5.1% e 5.9%) foram semelhantes em ambos os grupos de doentes (p=1). Conclusões 1. A radioterapia intersticial da próstata com implante transperineal e ecoguiado de Iodo 125 é frequentemente acompanhada de morbilidade urinária transitória e de intensidade moderada. A Morbilidade consiste em sintomatologia do aparelho urinário baixo (“LUTS – lower urinary tract symptoms”) que, na maioria dos doentes, sofre um agravamento máximo do primeiro ao 3.º mês. Segue-se uma melhoria ligeira até ao 6.º mês que é mais acentuada daí em diante. Por volta do 12.º e 18.º mês, a maior parte dos doentes apresenta sintomatologia urinária muito semelhante à que apresentava antes do tratamento. Após o 18.º mês, os doentes mantêm uma melhoria da sintomatologia urinária para além da que apresentavam previamente ao implante. As taxas de retenção urinária e de ressecção transuretral prostática após o implante de braquiterapia são muito baixas, inferiores a 10%. 2. A associação da braquiterapia prostática com radioterapia externa adjuvante influencia a evolução da sintomatologia urinária: o aparecimento da sintomatologia urinária é mais lento, demorando 6 meses a atingir o seu valor máximo que, por sua vez, é de intensidade menos acentuada do que quando a braquiterapia é utilizada em monoterapia. 3. O volume prostático superior a 50 ml não influencia a morbilidade urinária. 4. A terapêutica hormonal, neoadjuvante e adjuvante, não influencia a sintomatologia urinária. 5. Os doentes com sintomatologia urinária prévia muito acentuada não sofrem agravamento da referida sintomatologia. Pelo contrário, apresentam uma melhoria de sintomas urinários desde o primeiro mês, e que se mantém ao longo dos 24 meses de seguimento, apresentando, no final deste período, sintomatologia urinária ligeira e muito inferior à que apresentavam antes do implante. As taxas de retenção urinária e RTU-P após a braquiterapia são semelhantes às que ocorrem nos doentes assintomáticos previamente ao implante. 6. A vida sexual está preservada, em mais de 70% dos casos, ao fim dos 24 meses de seguimento. No entanto, imediatamente após o primeiro mês de seguimento, ocorre uma diminuição ligeira da qualidade das erecções que se mantém, sem melhoria ou agravamento, durante todo o período de seguimento. A hormonoterapia afecta todos os parâmetros da vida sexual, embora de forma apenas temporária. Após a suspensão da terapêutica hormonal este grupo de doentes recupera a actividade sexual e apresenta-se idêntico ao grupo de doentes que não foram sujeitos a essa terapêutica.----------------ABSTRACT: Objectives 1. To assess urinary and sexual morbility after prostatic brachytherapy with the implant of I125 seeds. 2. To assess the influence of neoadjuvant and adjuvant hormone therapy in urinary and sexual morbility after prostatic brachytherapy with the implant of I125 seeds. 3. To assess the effects, on urinary and sexual morbility, of associating external radiotherapy after prostatic brachytherapy with the implant of I125 seeds. 4. To assess the urinary morbility in patients with relative contraindications (voluminous prostates, high IPSS). Material and Methods From September, 2000 to December, 2004 a total of 204 patients were recruited with a diagnosis of localized (T1 and T2) or locally advanced (T3) carcinoma of the prostate and a life expectancy in excess of 10 years. The patients underwent brachytherapy with transperineal seed implant of iodine (I125) as a monotherapy or in combination with hormone therapy and/or external radiotherapy (trimodal treatment). With the aim of evaluating the treatment’s influence on urinary and sexual morbility, a number of patient sub-groups were defined in accordance with certain characteristics normally mentioned as morbility risk factors for prostatic brachytherapy treatment: Group 1: Brachytherapy as monotherapy (MONO) versus brachytherapy in combination with external radiotherapy (BCOMB) Group 2: Voluminous prostates (>50ml) versus non- voluminous prostates (<50ml) Group 3: Brachytherapy in combination with hormone therapy (HORM) versus brachytherapy without hormone therapy (NHORM)Group 4: High IPSS versus a low IPSS. The evolution of the IPSS, QoL, TURP rate and post-implant urinary retention as well as the BSFI were assessed throughout the entire follow-up period. Results Group 1: For the MONO group the IPSS began at 7.1, and then rose to 16.1 and 15.9 in the first and third months, respectively. At month 12, the IPSS had dropped to 10.1 and at month 18 and 24 the IPSS was registered at 7.3 and 5.8, respectively. The BCOMB group started out with an IPSS of 9.4. It underwent a slight and little-significant rise until month 6 (IPSS at 14). The evolution of the IPSS then began to fluctuate from an IPSS of 5.9 at month 12 and 9.5 at month 18. At month 24 we registered an IPSS of 6.7. The urinary retention rate (6.4% and 0%) and TURP rate (2.0% e 0%) were similar to those of the MONO and BCOMB groups, respectively (p=0.375 and p=1). The evolution regarding the quality of erections was similar for the two groups except at 6 months when the MONO group displayed a value of 6 and the BCOMB group 3.7 (p=0.029). The percentage of sexually potent patients was significantly lower in the first six months after brachytherapy for the BCOMB group when compared with the MONO group: 36%–74%; 33%–73%; 33%–75%. After six months, the results became more consistent. Group 2: IPSS results evolved in <50ml and >50ml prostates from 7–9 to 15-19 in the first month and from 15-18 after the third month. It was only in the first month that the differences in the IPSS were significant (p=0.061). After the third month, the two groups displayed similar outcomes: IPSS 8 and 12 at month 12 and 5.7 and 6 at month 24. Urinary retention and TURP rates were similar (p=0.054 e p=0.286). Group 3: IPSS evolution and rates of urinary retention and TURP were identical in both groups. Figures regarding libido, erections, percentage of sexually potent patients, ejaculation, discomfort and sexual satisfaction were always significantly lower for the HORM group, when compared to the NHORM group in the first month only (values of p<0.0001; <0.0001; <0.0001; 0.009 e 0.002, respectively). Group 4: IPSS evolution in patients with a high IPSS was as follows: 22.17(0M); 19.5(1M); 20.5(3M); 15.3(6M); 15.7(12M); 11(18M); 8(24M) IPSS evolution in patients with a low IPSS was as follows: 5.9(0M); 15.3(1M); 14.9(3M); 12.2(6M); 8.9(12M); 7.2(18M), 5.5(24M)TURP rates (2.8% e 0%) and those for urinary retention (5.1% e 5.9%) were similar in both patient groups (p=1). Conclusions 1. Interstitial radiotherapy of the prostate with transperineal, ultrasound-guided implant of Iodine-125 seeds is often followed by transitory urinary morbility of moderate intensity. The morbility involves symptoms of the lower urinary tract which, in most cases are at their worst from the first to the third months. There is a slight improvement up to the sixth month, at which point improvement becomes more accentuated. Around months 12 or 18, most patients display urinary symptoms that are very similar to those noted before treatment. After month 18, patients’ urinary symptoms continue to improve past the point they displayed prior to the implant. Urinary retention rates and those for transurethral resection of the prostate are very low (below 10%), after brachytherapy seed implant. 2. The combination of prostatic brachytherapy and adjuvant external radiotherapy affects the evolution of urinary symptoms: the appearance of urinary symptoms is much slower, taking six months to peak, and is less intense than when brachytherapy is employed as the only means of treatment. 3. The fact that the prostate displays a volume greater than 50 ml does not influence urinary morbility. 4. Neoadjuvant and adjuvant hormone therapy do not influence urinary symptomology. 5. Patients with severe, preexisting symptoms of the urinary tract do not experience a worsening of those symptoms. On the contrary, they exhibit an improvement in urinary symptoms as of the first month. This improvement continues for the 24 months, after which patients display symptoms of the urinary tract that are slight and a noticeable improvement over the urinary complaints registered before the implant. Urinary retention and TURP rates subsequent to brachytherapy are similar to those registered for asymptomatic patients. 6. The patient’s sexual performance is maintained in more than 70% of the cases, as noted after 24 months of follow-up. However, immediately after the first follow-up month there is a lessening in the quality of erections that continues, without improving or worsening, for the whole follow-up period. Hormone therapy affects all the parameters of sexual performance, albeit temporarily. After suspending hormone therapy, this group recovered with regard to sexual performance, and showed itself to be identical to the group of patients that had not undergone hormone therapy.-------------------RESUMÉ:Objectives 1. Évaluer la morbilité urinaire et sexuelle après la realisation la curiethérapie de la prostate avec implant de I125. 2. Évaluer l’ influence de la thérapie hormonale néoadjuvante et adjuvante en ce qui concerne la morbilité urinaire et sexuelle après la réalisation de la curiethérapie (I125). 3. Évaluer l’influence de l’association de la radiothérapie externe dans la morbilité urinaire et sexuelle après la réalisation de la curiethérapie (I125). 4. Évaluer la morbilité urinaire des malades avec des contre indications relatives (prostates volumineuses, IPSS élevé). Matériel et méthodologie De Septembre 2000 à Décembre 2004, on a recruté 204 patients ayant pour diagnostique un carcinome de la prostate localisé (T1 et T2) ou localement avancé (T3) et dont l’expectative de vie était de plus de 10 ans. Ils ont été soumis au traitement de la curiethérapie avec l’implantation transpérinéal de l’iode 125 (I125) en monothérapie ou en traitement combiné avec une thérapie hormonale et/ou radiothérapie externe (traitement trimodale). Il y a eu plusieurs sous-catégories de patients, et cela dépend de quelques caractéristiques normalement considérées comme des facteurs à risque en ce qui concerne la morbilité du traitement de la curiethérapie de la prostate, et l’objective étant d’analyser son influence sur la morbilité urinaire et sexuelle. Groupe 1: Curiethérapie en traitement unique (MONO) par rapport à la curiethérapie associée au traitement externe (BCOMB). Groupe 2: Prostates volumineuses (>50ml) par rapport au prostates qui ne sont pas volumineuses (<50ml). Groupe 3: Curiethérapie associée au traitement hormonale (HORM) par rapport à la curiethérapie sans traitement hormonale (NHORM). Groupe 4: IPSS élevé par rapport au IPSS diminué. Nous avons évalué l’evolution du IPSS, Qualité de vie, le taux de RTU-P et la retention de l’urine après l’implant, BSFI pendant toute la période du traitement. Résultats Groupe 1: Pour le groupe MONO l’IPSS a commençé avec un taux de 7.1, et les patients ont souffert d’un empirement allant jusqu’à 16.1 et 15.9 pendant le premier et le troisième mois. 12 mois après l’IPSS diminua jusqu’à 10.1 À 18 mois le taux fût de 7.3 et à 24 mois il diminua encore jusqu’à atteindre 5.8. Le groupe BCOMB commença avec un taux d’IPSS de 9.4. Ils souffrirent un empirement légér et peu accentué jusqu’aux 6 premiers mois (IPSS de 14). L’évolution de l’IPSS était fluctuante allant de 5.9 à 12 mois et 9.5 à 18 mois. À 24 mois, l’IPSS était de 6.7. Le taux de retention de l’urine (6.4% et 0%) et de la RTU-P (2.0% et 0%) étaient simmilaires dans les groupes MONO et BCOMB respectivement (p=0.375 et p=1). L’ évolution de la qualité des érections fût semblable dans les 2 groupes excepté le groupe MONO qui présenta une valeure de 6 à 6 mois et le groupe BCOMB qui présenta une valeure de 3.7 (p=0.029). Le pourcentage des malades sexuellement puissants a été significativement inférieur pendant les 6 premiers mois depuis la curiethérapie pour le groupe BCOMB si on le compare au groupe MONO: 36%–74%; 33%–73%; 33%–75%. Après cette période, les groupes eûrent des résultats homogénes. Groupe 2: L’ IPSS a évolué dans les prostates <50ml et >50ml de 7–9 jusqu’à 15-19 pendant le premier mois et jusqu’à 15-18 au 3ème mois. C’est seulement pendant le premier mois que les différences de l’IPSS ont été significatives (p=0.061). Après le 3ème mois les deux groupes ont eu des résultats semblables: IPSS 8 et 12 à 12.º mois et 5.7 et 6 à 24.º mois. Le taux de retention de l’urine et de la RTU-P ont été simmilaires (p=0.054 e p=0.286). Groupe 3: L’evolution de l’ IPSS, les taux de retention de l’urine et de la RTU-P pourraient se surposer pour les deux groupes. L’évolution de la libido, des érections, le pourcentage des malades sexuellements puissants, l’incommodité et la satisfaction ont été toujours significativement infériures dans le groupe HORM par rapport au groupe NHORM dès le premier mois (valeurs de p <0.0001; <0.0001; < 0.0001; 0.009 et 0.002 respectivement) Groupe 4: L’évolution de l’ IPSS pour les malades ayant un IPSS élevé fût ainsi: 22.17(0M); 19.5(1M); 20.5(3M); 15.3(6M); 15.7(12M); 11(18M); 8(24M)L’évolution de l’ IPSS pour les malades ayant un IPSS diminué fût ainsi:5.9(0M); 15.3(1M); 14.9(3M); 12.2(6M); 8.9(12M); 7.2(18M), 5.5(24M) Le taux de RTU-P (2.8% e 0%) et de retention de l’urine (5.1% et 5.9%) ont été semblables dans les 2 groupes de malades (p=1). Conclusions 1. La radiothérapie interstitielle de la prostate avec implant transpérinéal de l’iode 125 est fréquamment acompagnée d’une morbilité urinaire transitoire et d’intensité modérée. La morbilité consiste d’une symptomatologie de l’apparéil urinaire inférieure qui, dans la plupart des malades, empire gravement du premier au troisième mois. La situation s’améliore légèrement jusqu’au 6ème mois, l’amélioration étant plus accentuée à partir de là. Autour du 12ème jusqu’au 18ème mois, la majorité des malades présente une symptomatologie urinaire qui se ressemble beaucoup à celle qu’ils avaient avant le traitement. Après le 18ème mois l’amélioration de la symptomatologie urinaire est constante par rapport à celle qu’ils présentaient avant l’implant. Le taux de retention de l’urine et de RTU-P après l’implant de la curiethérapie sont très basses, au dessus de 10%. 2. L’association de la curiethérapie de la prostate avec la radiothérapie externe adjuvante a une influence sur l’évolution de la symptomatologie urinaire: l’apparition des symptômes est plus lente, prenant jusqu’à 6 mois pour atteindre son niveau maximum, qui à son tour, a une intensité moins accentuée que lorsque la curiethérapie est utilisée en monothérapie. 3. Le volume de la prostate supérieure à 50 ml n’a pas d’influence sur la morbilité urinaire. 4. La thérapie hormonale, néoadjuvante et adjuvante, n’a pas d’influence sur la symptomatologie urinaire. 5. Les malades ayant une symptomatologie urinaire préalable et très accentuée ne souffrent pas d’empirement de leur situation. Au contraire, ils présentent une amélioration des symptômes urinaires à partir du premier mois et ceci se maintient tout au long des 24 mois que dure le traitement, ayant à la fin de cette période une symptomatologie urinaire légère et beaucoup plus basse que celle qu’ils présentaient avant l’implant. Le taux de retention de l’urine et de la RTU-P après la curiethérapie est simmilaire à celui que les malades qui n’ont pas de symptômes présentent avant l’implant. 6. La vie sexuelle est préservée dans plus du 70% des cas à la fin de la période de traitement (24 mois). Entretemps, immédiatement après le premier mois d’étude, on note une légère diminution de la qualité des érections qui se maintient sans amélioration ou empirement tout au long du traitement. Le traitement à base d’hormones affecte tous les paramètres de la vie sexuelle, mais de façon temporaire. Après la suspension de la thérapie hormonale ce groupe de malades récupère l’activité sexuelle et se présente de façon égale au groupe de malades qui n’ont pas été soumis à ce traitement.

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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente

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Due to their toxicity, especially their carcinogenic potential, polycyclic aromatic hydrocarbons (PAHs) became priority pollutants in biomonitoring programmes and environmental policy, such as the European Water Framework Directive. The model substances tested in this study, namely benzo[b]fluoranthene (B[b]F), considered potentially carcinogenic to humans and an effector carcinogenic PAH to wildlife, and phenanthrene (Phe), deemed a non-carcinogenic PAH, are common PAHs in coastal waters, owning distinct properties reflected in different, albeit overlapping, mechanisms of toxicity. Still, as for similar PAHs, their interaction effects remain largely unknown. In order to study the genotoxic effects of caused by the interaction of carcinogenic and non-carcinogenic PAHs, and their relation to histopathological alterations, juvenile sea basses, Dicentrarchus labrax, a highly ecologically- and economically-relevant marine fish, were injected with different doses (5 and 10 μg.g-1 fish ww) of the two PAHs, isolated or in mixture, and incubated for 48 h. Individuals injected with B[b]F and the PAH mixture exhibited higher clastogenic/aneugenic effects and DNA strand breakage in blood cells, determined through the erythrocytic nuclear abnormalities (ENA) and Comet assays, respectively. Also, hepatic histopathological alterations were found in all animals, especially those injected with B[b]F and the PAH mixture, relating especially to inflammation. Still, Phe also exhibited genotoxic effects in sea bass, especially in higher doses, revealing a very significant acute effect that was accordant with the Microtox test performed undergone in parallel. Overall, sea bass was sensitive to B[b]F (a higher molecular weight PAH), likely due to efficient bioactivation of the pollutant (yielding genotoxic metabolites and reactive oxygen species), when compared to Phe, the latter revealing a more significant acute effect. The results indicate no significant additive effect between the substances, under the current experimental conditions. The present study highlights the importance of understanding PAH interactions in aquatic organisms, since they are usually present in the aquatic environment in complex mixtures.

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Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous priority pollutants that tend to be trapped in aquatic sediments due to their high hydrophobicity. Nonetheless, the differential toxicological effects and mechanisms between the various classes of PAHs and their mixtures, as they invariably occur in the environment, are scarcely known, especially under ecologically-relevant scenarios. This thesis aimed at establishing a bridge between the study of mechanistic pathways and environmental monitoring of carcinogenic and non-carcinogenic PAHs, by introducing ecological-relevance in the research with model PAHs. A first bioassay conducted in situ with the mussel Mytilus edulis demonstrated that, dredging operations in harbours increase PAH bioavailability, eliciting genotoxicity, and showed that established environmental guidelines underestimate risk. Subsequent ex situ bioassays were performed with the carcinogenic benzo[b]fluoranthene (B[b]F) and non-carcinogenic phenantrene (Phe), selected following preceding results, and revealed that low-moderate concentrations of these PAHs in spiked sediments induce genotoxic effects to the clam Ruditapes decussatus, therefore contradicting the general notion that bivalves are less sensitive to PAHs than vertebrates due to inefficient bioactivation. Also, it was demonstrated that passive samplers permit inferring on PAH bioavailability but not on bioaccumulation or toxic effects. On the other hand, sea basses (Dicentrarchus labrax), yielded a complex pattern of effects and responses, relatively to genotoxicity, oxidative stress and production of specific metabolites, especially when exposed to mixtures of the PAHs which led to additive, if not synergistic, effects. It was shown that Phe may elicit significant genotoxicity especially in presence of B[b]F, even though the low, albeit realistic, exposure concentrations diluted dose- and time-independent relationships. The present work demonstrated that environmental quality guidelines underestimate the effects of PAHs in realistic scenarios and showed that the significant genotoxic and histopathological effects caused by mixed PAHs may not be reflected by oxidative stress- or CYP-related biomarkers. Besides important findings on the metabolism of PAH mixtures, the work calls for the need to re-evaluate the criteria for assessing risk and for the disclosure of more efficient indicators of toxicological hazard.

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Estudi arqueològic integrat de la vall del Madriu-Perafita-Claror (Andorra) iniciat al 2004 sota la coordinació de l’ICAC. L’estudi s’insereix en la declaració de la vall com a Patrimoni de la Humanitat (UNESCO). Las recerques s’enfoquen des de l’Arqueologia del Paisatge, de manera diacrònica i pluridisciplinar, fent especial atenció a les relacions de les societats amb el medi. Les restes arqueològiques treballades s’associen a activitats ramaderes, metal•lúrgiques i de carboneig. La recerca paleoecològica se centra en sediments lacustres, torbosos i arqueològics. L’any 2006, s’han analitzat a alta resolució temporal dues seqüencies palinològiques: l’estany Blau (2471 m) i la torbera de Bosc dels Estanyons (2180 m), obtenint les principals fases d’explotació i antropització d’aquest espai altimontà, així com l’evolució del paisatge en els darrers 11000 anys . La campanya de camp s’ha centrat en l’obtenció de mostres de pluja pol•línica referencial a la vall i en el sondatge de l’estany Forcat (2539 m). Un total de tres mostres han estat enviades a datar per C14. Els treballs arqueològics s’han centrat en l’excavació de sondejos de diagnòstic als jaciments de Basses de Setut (2325 m) i Pleta de les Bacives ( 2530 m) i en la realització de prospeccions a les capçaleres de les valls de Madriu, Perafita i Claror. S’han documentat estructures arqueològiques i s’han realitzat estudis antracològics dels sediments excavats en aquestes. S’ha realitzat un transecte altitudinal de carboneres al llarg de la vall per tal de enregistrar una major diversitat cronològica dels espais de carboneig. S’han enviat datacions C14 per tal de determinar la cronologia de les estructures. Les datacions del 2005 mostren una intensa ocupació ramadera i de carboneig a partir del segle XIV, en època baixmedieval i moderna, així com un establiment metal·lúrgic d’època romana.

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Abstract Part I : Background : Isolated lung perfusion (ILP) was designed for the treatment of loco-regional malignancies of the lung. In contrast to intravenous (IV) drug application, ILP allows for a selective administration of cytostatic agents such as doxorubicin to the lung while sparing non-affected tissues. However, the clinical results with ILP were disappointing. Doxorubicinbased ILP on sarcoma rodent lungs suggested high overall doxorubicin concentrations within the perfused lung but a poor penetration of the cytostatic agent into tumors. The same holds true for liposomal-encapsulated macromolecular doxorubicin (LiporubicinTM) In specific conditions, low-dose photodynamic therapy (PDT) can enhance the distribution of macromolecules across the endothelial bamer in solid tumors. It was recently postulated that tumor neovessels were more responsive to PDT than the normal vasculature. We therefore hypothesized that Visudyne®-mediated PDT could selectively increase liposomal doxorubicin (LiporubicinTM) uptake in sarcoma tumors to rodent lungs during intravenous (IV) drug administration and isolated lung perfusion (ILP). Material and Methods : A sarcoma tumor was generated in the left lung of Fisher rats by subpleural injection of a sarcoma cell ,suspension via thoracotomy. Ten days later, LiporubicinTM is administered IV or by single pass antegrade ILP, with or without Visudyne® -mediated low-dose PDT pre-treatment of the sarcoma bearing lung. The drug concentration and distribution were assessed separately in tumors and lung tissues by high pressure liquid chromatography (HPLC) and fluorescence microscopy (FNI~, respectively. Results : PDT pretreatment before IV LiporubicinTM administration resulted in a significantly higher tumor drug uptake and tumor to lung drug ratio compared to IV drug injection alone without affecting the blood flow and drug distribution in the lung. PDT pre-treatment before LiporubicinTM-based ILP also resulted in a higher tumor drug uptake and a higher tumor to lung drug ratio compared to ILP alone, however, these differences were not significant due to a heterogeneous blood flow drug distribution during ILP which was further accentuated by PDT. Conclusions : Low-dose Visudyne®-mediated PDT pre-treatment has the potential to selectively enhance liposomal encapsulated doxorubicin uptake in tumors but not in normal lung tissue after IV drug application in a rat model of sarcoma tumors to the lung which opens new perspectives for the treatment of superficially spreading chemoresistant tumors of the chest cavity such as mesothelioma or malignant effusion. However, the impact of PDT on macromolecular drug uptake during ILP is limited since its therapeutic advantage is circumvented by ILP-induced heterogeneicity of blood flow and drug distribution Abstract Part II Background : Photodynamic therapy (PDT) with Visudyne® acts by direct cellular phototoxicity and/or by an indirect vascular-mediated effect. Here, we demonstrate that the vessel integrity interruption by PDT can promote the extravasation of a macromolecular agent in normal tissue. To obtain extravasation in normal tissue PDT conditions were one order of magnitude more intensive than the ones in tissue containing neovessels reported in the literature. Material and Methods : Fluorescein isothiocyanate dextran (FITC-D, 2000kDa), a macromolecular agent, was intravenously injected 10 minutes before (LKO group, n=14) or 2 hours (LK2 group, n=16) after Visudyne® mediated PDT in nude mice bearing a dorsal skin fold chamber. Control animals had no PDT (CTRL group, n=8). The extravasation of FITC-D from blood vessels in striated muscle tissue was observed in both groups in real-time for up to 2500 seconds after injection. We also monitored PDT-induced leukocyte rolling in-vivo and assessed, by histology, the corresponding inflammatory reaction score in the dorsal skin fold chambers. Results : In all animals, at the applied PDT conditions, FITC-D extravasation was significantly enhanced in the PDT treated areas as compared to the surrounding non-treated areas (p<0.0001). There was no FITC-D leakage in the control animals. Animals from the LKO group had significantly less FITC-D extravasation than those from the LK2 group (p = 0.0002). In the LKO group FITC-D leakage correlated significantly with the inflammation (p < 0.001). Conclusions: At the selected conditions, Visudyne-mediated PDT promotes vascular leakage and FITC-D extravasation into the interstitial space of normal tissue. The intensity of vascular leakage depends on the time interval between PDT and FITC-D injection. This concept could be used to locally modulate the delivery of macromolecules in vivo. Résumé : La perfusion cytostatique isolée du poumon permet une administration sélective des agents cytostatiques sans implication de la circulation systémique avec une forte accumulation au niveau du poumon mais une faible pénétration dans les tumeurs. La thérapie photodynamique (PDT) qui consiste en l'application d'un sensibilisateur activé par lumière laser non- thermique d'une longueur d'onde définie permet dans certaines conditions, une augmentation de la pénétration des agents cytostatiques macromoléculaires à travers la barrière endothéliale tumorale. Nous avons exploré cet avantage thérapeutique de la PDT dans un modèle expérimental afin d'augmenter d'une manière sélective la pénétration tumorale de la doxorubicin pegylée, liposomal- encapsulée macromoléculaire (Liporubicin). Une tumeur sarcomateuse a été générée au niveau du poumon de rongeur suivie d'administration de Liporubicin, soit par voie intraveineuse soit par perfusion isolée du poumon (ILP). Une partie des animaux ont reçus un prétraitement de la tumeur et du poumon sous jacent par PDT avec Visudyne comme photosensibilisateur. Les résultats ont démontrés que la PDT permet, sous certaines conditions, une augmentation sélective de Liporubicin dans les tumeurs mais pas dans le parenchyme pulmonaire sous jacent. Après administration intraveineuse de Liporubicin et prétraitement par PDT, l'accumulation dans les tumeurs était significative par rapport au poumon, et aux tumeurs sans PDT. Le même phénomène est observé après ILP du poumon. Cependant, les différences avec ou sans PDT n'étaient pas significatives lié à und distribution hétérogène de Liporubicin dans le poumon perfusé après ILP. Dans une deuxième partie de l'expérimentation, nous avons exploré la microscopie intra-vitale pour déterminer l'extravasion des substances macromoléculaires (FITS) à travers la barrière endothéliale avec ou sans Visudyne-PDT au niveau des chambres dorsales des souris nues. Les résultats montrent qu'après PDT, l'extravasion de FITS a été augmentée de manière significative par rapport au tissu non traité. L'intensité de l'extravasion de FITS dépendait également de l'intervalle entre PDT et injection de FITS. En conclusion, les expérimentations montrent que la PDT est capable, sous certaines conditions, d'augmenter de manière significative l'extravasion des macromolécules à travers la barrière endothéliale et leur accumulation dans des tumeurs mais pas dans le parenchyme pulmonaire. Ces résultats permettent une nouvelle perspective de traitement pour des tumeurs superficielles intrathoraciques chimio-résistent comme l'épanchement pleural malin ou le mésothéliome pleural.