957 resultados para mono dicotiledôneas
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The factors responsible for the phenotypic heterogeneity of memory CD4 T cells are unclear. In the present study, we have identified a third population of memory CD4 T cells characterized as CD45RA(+)CCR7(-) that, based on its replication history and the homeostatic proliferative capacity, was at an advanced stage of differentiation. Three different phenotypic patterns of memory CD4 T cell responses were delineated under different conditions of antigen (Ag) persistence and load using CD45RA and CCR7 as markers of memory T cells. Mono-phenotypic CD45RA(-)CCR7(+) or CD45RA(-)CCR7(-) CD4 T cell responses were associated with conditions of Ag clearance (tetanus toxoid-specific CD4 T cell response) or Ag persistence and high load (chronic HIV-1 and primary CMV infections), respectively. Multi-phenotypic CD45RA(-)CCR7(+), CD45RA(-)CCR7(-) and CD45RA(+)CCR7(-) CD4 T cell responses were associated with protracted Ag exposure and low load (chronic CMV, EBV and HSV infections and HIV-1 infection in long-term nonprogressors). The mono-phenotypic CD45RA(-)CCR7(+) response was typical of central memory (T(CM)) IL-2-secreting CD4 T cells, the mono-phenotypic CD45RA(-)CCR7(-) response of effector memory (T(EM)) IFN-gamma-secreting CD4 T cells and the multi-phenotypic response of both IL-2- and IFN-gamma-secreting cells. The present results indicate that the heterogeneity of different Ag-specific CD4 T cell responses is regulated by Ag exposure and Ag load.
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BACKGROUND: While detoxification under anaesthesia accelerates the detoxification procedure, there is a lack of randomised clinical trials evaluating its effectiveness compared to traditional detoxification procedures, and a lack of data on long-term abstinence. METHODS: Prospective randomised clinical trial. Analysis by intention to treat and per protocol. Setting: Specialised substance abuse unit in a psychiatric teaching hospital and an intensive care unit of a general hospital. Participants: Seventy patients with opiate mono-dependence requesting detoxification: 36 randomised to RODA (treatment as allocated received by 26) and 34 randomised to classical clonidine detoxification (treatment as allocated received by 21). Main outcome measures: Successful detoxification, safety and self-reported abstinence at 3, 6 and 12 months after detoxification. RESULTS: Socio-demographics were similar in both groups at baseline. No complications were reported during or after anaesthesia. According to the intention to treat analysis, 28/36 (78%) RODA patients and 21/34 (62%) of the clonidine group successfully completed the detoxification process (p=0.14). In the intention to treat analysis, 30% of RODA patients were abstinent after 3 months compared to 14% in the clonidine group (p=0.11). No difference was found at 6 and 12 months (both groups showed less than 5% abstinence after 12 months). The per-protocol analysis showed similar results with no statistical differences either for ASI mean scores or for the SF36 questionnaire. CONCLUSION: Although the detoxification success rate and abstinence after 3 months were slightly better for the RODA procedure compared to clonidine treatment, these differences were not statistically significant and disappeared completely after 6 and 12 months.
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The aberrant accumulation of lipids in the liver ("fatty liver") is tightly associated with several components of the metabolic syndrome, including type 2 diabetes, coronary heart disease, and atherosclerosis. Here we show that the impaired hepatic expression of transcriptional cofactor transducin beta-like (TBL) 1 represents a common feature of mono- and multigenic fatty liver mouse models. Indeed, the liver-specific ablation of TBL1 gene expression in healthy mice promoted hypertriglyceridemia and hepatic steatosis under both normal and high-fat dietary conditions. TBL1 deficiency resulted in inhibition of fatty acid oxidation due to impaired functional cooperation with its heterodimerization partner TBL-related (TBLR) 1 and the nuclear receptor peroxisome proliferator-activated receptor (PPAR) α. As TBL1 expression levels were found to also inversely correlate with liver fat content in human patients, the lack of hepatic TBL1/TBLR1 cofactor activity may represent a molecular rationale for hepatic steatosis in subjects with obesity and the metabolic syndrome.
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OBJECTIVE: To examine predictors of stroke recurrence in patients with a high vs a low likelihood of having an incidental patent foramen ovale (PFO) as defined by the Risk of Paradoxical Embolism (RoPE) score. METHODS: Patients in the RoPE database with cryptogenic stroke (CS) and PFO were classified as having a probable PFO-related stroke (RoPE score of >6, n = 647) and others (RoPE score of ≤6 points, n = 677). We tested 15 clinical, 5 radiologic, and 3 echocardiographic variables for associations with stroke recurrence using Cox survival models with component database as a stratification factor. An interaction with RoPE score was checked for the variables that were significant. RESULTS: Follow-up was available for 92%, 79%, and 57% at 1, 2, and 3 years. Overall, a higher recurrence risk was associated with an index TIA. For all other predictors, effects were significantly different in the 2 RoPE score categories. For the low RoPE score group, but not the high RoPE score group, older age and antiplatelet (vs warfarin) treatment predicted recurrence. Conversely, echocardiographic features (septal hypermobility and a small shunt) and a prior (clinical) stroke/TIA were significant predictors in the high but not low RoPE score group. CONCLUSION: Predictors of recurrence differ when PFO relatedness is classified by the RoPE score, suggesting that patients with CS and PFO form a heterogeneous group with different stroke mechanisms. Echocardiographic features were only associated with recurrence in the high RoPE score group.
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Rapport de synthse : L'infection par le virus de l'hpatite C (VHC) a une volution svre chez les patients co-infects par VIH/VHC, de mme que chez les patients transplants hpatiques. Toutefois, les mcanismes impliqus dans cette volution restent peu clairs. Dans ce travail, nous tudions le profil fonctionnel des cellules T spcifiques diriges contre le virus de l'hpatite C chez 86 patients mono-infects par VHC, 48 patients co-infects par VIH/VHC et 42 patients ayant bnfici d'une transplantation hpatique. La production d'IFN-Y et d'IL-2 et la capacit de prolifrer des cellules T CD4+ et CD8+ sont values aprs stimulation par des peptides drivs du VHC. Chez les patients mono-infects par le VHC, les cellules T spcifiques au VHC sont polyfonctionnelles du point de vue de la scrtion de cytokines, avec trois profils de scrtion pour les cellules T CD4+: scrtion uniquement de IL-2, scrtion de IL-2 et IFN-y et scrtion uniquement de IFN-gamma, et de deux profils pour les cellules T CD8+: scrtion de IL-2 et IFN-y et scrtion uniquement de IFN-gamma. En revanche, les cellules T spcifiques au VHC chez les individus coinfects par VIH/VHC et chez les patients transplants hpatiques ont un profil de scrtions de cytokines marqu par l'absence de cellules CD4+ scrtant uniquement l'Il-2 et l'absence de cellules CD8+ scrtant la fois IL-2 et IFN-gamma. De plus, la prolifration de cellules T CD4+ et CD8+ spcifiques au VHC est considrablement rduite chez les patients co-infects par VIH/VHC, comme chez les transplants hpatiques. La prsence de cellules T effectrices uniquement (dfinies par l'absence de cellules T CD4+ scrtants uniquement de l'IL-2 et l'absence de cellules T CD8+ scrtant la fois IL-2 et IFN-gamma et altration de la capacit prolifrative) est associe avec une charge virale VHC significativement plus leve et une fibrose hpatique plus svre. Par consquent, les prsents rsultats suggrent la participation de mcanismes immunitaires dans l'volution acclre de l'hpatite C chez les patients co-infects par VIH-1 et chez les patients greffs hpatiques.
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O Projecto Flora de Cabo Verde uma iniciativa conjunta do Instituto de Investigao Cientfica Tropical (IICT) e do Instituto Nacional de Investigao e Desenvolvimento Agrrio (INIDA) de Cabo Verde, iniciado em 1990. O objectivo do projecto a publicao, em portugus e em forma de Flora, de fascculos contendo, cada um, o estudo de uma famlia de plantas vasculares ocorrendo no Arquiplago de Cabo Verde, tanto as nativas, em que se incluem as endmicas, como as exticas naturalizadas. A obra dirigida por uma Comisso Editorial constituda por dois elementos do IICT, dois do INIDA e um do Instituto Botnico de Coimbra. O estudo das diversas famlias feito de acordo com o sistema de classificao de Cronquist, de utilizao comum na regio oeste-africana. O tratamento taxonmico o mais uniforme possvel. Todos os taxa so introduzidos em chaves dicotmicas para permitir uma rpida distino com recurso a caractersticas facilmente observveis e descritos morfologicamente. Para cada espcie ou taxon infra-especfico citada a bibliografia respectiva respeitante rea geogrfica, assim como as sinonmias igualmente respeitantes rea. referida a sua distribuio em Cabo Verde com uma ou duas citaes de materiais por ilha e a distribuio mundial. So ainda feitas referncias ecologia, utilizaes e nomes vulgares nas diversas ilhas. A obra iconografada com estampas relativas a todos os gneros com espcies nativas ou naturalizadas. A base do estudo constituda pelos materiais depositados nos diversos herbrios que reconhecidamente possuem plantas colectadas na regio, com particular nfase nos Herbrios do Instituto de Investigao Cientfica Tropical (LISC), do Instituto Nacional de Investigao e Desenvolvimento Agrrio, de Cabo Verde (CECV), do Instituto Botnico da Universidade de Coimbra (COI), do Instituto Botnico da Universidade de Lisboa (LISU), do Musum National dHistoire Naturelle, de Paris (P) e do Botanical Garden and Museum, de Oslo (O). Quando finalizada, a Flora de Cabo Verde ir abranger mais de 700 taxa pertencentes a diversas famlias de Pteridfitos, a 97 famlias de Dicotiledneas e a 18 famlias de Monocotiledneas. At data foram publicadas 88 famlias, incluindo 232 gneros e 417 taxa. Este projecto, ao ter por finalidade o conhecimento da diversidade vegetal nas ilhas do Arquiplago, constituir um suporte bsico para outros tipos de estudos como sejam a caracterizao da vegetao, a avaliao de impactos ambientais, o planeamento de polticas ambientais e agrrias ou conservao da biodiversidade.
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Intro. Le syndrome post-thrombotique (SPT) est la complication chronique la plus frquente aprs une thrombose veineuse profonde (TVP). Syndrome peu connu, malgr une prvalence de 20-50%, il se caractrise par des symptmes d'insuffisance veineuse chronique apparaissant aprs une TVP. L'utilisation de bas de compression gradue (BCG) diminue de moiti le risque de dvelopper un SPT. Mais un problme de faible compliance est souvent un obstacle dans la prise en charge. Le but principal de cette tude sera de dterminer le lien entre l'adhrence au BCG et le dveloppement de SPT Mthode. Il s'agit d'une tude cas-tmoin, mono-centrique, avec inclusion prospective et conscutive des patients avec une TVP. Les patients recruts recevront un traitement standard pour une TVP (anticoagulation thrapeutique pendant 3 mois et BCG pour une dure d'un an) et seront suivis sur une anne avec 4 visites mdicales (V0-V3) et 10 entretiens tlphoniques (I1-I10). A la fin de l'tude, sur la base de l'adhrence au port du BCG, les patients seront diviss en deux groupes: bonne adhrence au traitement (cas) et faible adhrence (tmoin). Conclusion. Il est certain que ce sujet a besoin de recherches pour mieux comprendre le dveloppement, trouver une prvention et des traitements efficaces et acceptables afin d'amliorer leur qualit de vie des patients.
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Com o objectivo de se fazer um estudo restrito da flora autctone de So Vicente, realizou-se o presente trabalho, para se clarificar qual a situao actual da flora autctone da ilha, focalizando as potenciais reas de ocorrncia das mesmas. Com base nos inventrios florsticos realizados nos meses de Dezembro de 2006 e Abril de 2007, so apresentados neste trabalho, dados sobre a distribuio, o tamanho populacional e o estatuto de conservao de angiosprmicas autctones ocorrendo na ilha. Por conseguinte, apresentam-se, tambm, os principais locais de ocorrncia e uma avaliao quantitativa de 21 dos 35 taxa endmicos e de 1 arbusto indgena. Do total dos taxa endmicos, 21 so dicotiledneas e 1 monocotilednea, representantes de 16 famlias e 21 gneros destas duas divises, concluindo-se que a famlia Asteraceae a melhor representada, com 5 espcies. Realizou-se ainda, o esboo cartogrfico das espcies endmicas e indgenas em risco de extino e a monitorizao dos ecossistemas em que as mesmas se encontram inseridas evidenciando o seu grau de degradao. Populaes de espcies endmicas so apresentadas em vrios locais da ilha, destacando-se a nova populao de Limonium jovi-barba com 217 espcimes, encontrada no Carrial, bem como a populao relativamente grande de Euphorbia tuckeyana com 2320 espcimes inventariados no Madeiral. Identificaram-se ainda diferentes espcies raras, em pontos de relativa incidncia de factores degradativos, como o caso do Parque Natural do Monte Verde. Citam-se os exemplos de Aeonium gorgoneum (835 espcimes), Conyza pannosa (16 espcimes), Campanula jacobaea (16 espcimes), Lavandula rotundifolia (46 espcimes), Launaea gorgadensis (14 espcimes) e Sonchus daltonii (11 espcimes). Estas espcies apresentam elevado valor cientfico e socio-econmico, sendo aquelas encontradas em reduzido nmero.
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BACKGROUND & AIMS: In treatment-naive patients mono-infected with genotype 1 chronic HCV, treatments with telaprevir/boceprevir (TVR/BOC)-based triple therapy are standard-of-care. However, more efficacious direct-acting antivirals (IFN-based new DAAs) are available and interferon-free (IFN-free) regimens are imminent (2015). METHODS: A mathematical model estimated quality-adjusted life years, cost and incremental cost-effectiveness ratios of (i) IFN-based new DAAs vs. TVR/BOC-based triple therapy; and (ii) IFN-based new DAAs initiation strategies, given that IFN-free regimens are imminent. The sustained virological response in F3-4/F0-2 was 71/89% with IFN-based new DAAs, 85/95% with IFN-free regimens, vs. 64/80% with TVR/BOC-based triple therapy. Serious adverse events leading to discontinuation were taken as: 0-0.6% with IFN-based new DAAs, 0% with IFN-free regimens, vs. 1-10% with TVR/BOC-based triple therapy. Costs were euro60,000 for 12weeks of IFN-based new DAAs and two times higher for IFN-free regimens. RESULTS: Treatment with IFN-based new DAAs when fibrosis stage ⩾F2 is cost-effective compared to TVR/BOC-based triple therapy (euro37,900/QALY gained), but not at F0-1 (euro103,500/QALY gained). Awaiting the IFN-free regimens is more effective, except in F4 patients, but not cost-effective compared to IFN-based new DAAs. If we decrease the cost of IFN-free regimens close to that of IFN-based new DAAs, then awaiting the IFN-free regimen becomes cost-effective. CONCLUSIONS: Treatment with IFN-based new DAAs at stage ⩾F2 is both effective and cost-effective compared to TVR/BOC triple therapy. Awaiting IFN-free regimens and then treating regardless of fibrosis is more efficacious, except in F4 patients; however, the cost-effectiveness of this strategy is highly dependent on its cost.
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A tese que ora findamos visa a obteno do grau de doutora em Educao, na Especialidade de Desenvolvimento Curricular, pelo Departamento do Currculo e Tecnologia Educativa, do Instituto de Educao e Psicologia, da Universidade do Minho. Intitulado o dualismo cultural: os luso-caboverdianos entre a escola, a famlia e a comunidade, o presente estudo centra-se numa abordagem crtica da escolaridade bsica obrigatria, no qual procurmos compreender e explicar as condies de realizao deste nvel de ensino pelos jovens de ascendncia caboverdiana, nascidos em Portugal, na qualidade de sujeitos biculturais em consequncia da simbiose das culturas caboverdeana e portuguesa. Isto para concluirmos se na oferta do servio educativo e de formao esto acautelados os seus direitos de cidadania e de participao na sociedade em que se encontram inseridos e a que pertencem de facto. Nesta investigao foi fundamental analisar a oferta de educao bsica, entender as representaes de alunos lusocaboverdeanos acerca da sua identidade cultural e das suas percepes sobre a formao acadmica que recebem; reconhecer representaes e percepes de professores acerca da realidade educativa portuguesa, o enquadramento da multiculturalidade e a docncia em turmas com alunos luso-caboverdianos, e compreender as percepes de pais e encarregados da educao caboverdeanos acerca da realidade educativa portuguesa e do enquadramento dos seus filhos na escola, para perceber se o insucesso educativo dos luso-caboverdeanos est relacionado com a condio de aluno culturalmente diferente ou se tem a sua origem na escola e no currculo da escolaridade obrigatria e, assim, contribuir com subsdios tericos e prticos para o aprofundamento da problemtica da multiculturalidade em Portugal, com vista sua potenciao e normalizao no sistema educativo. Estando perante uma sociedade de formao multicultural reafirmada com a colonizao, justifica-se, em Portugal, a preocupao com a temtica da diversidade cultural nas polticas educativas, resultante da consciencializao da manifestao da diversidade cultural no contexto escolar, podendo a sua omisso constituir num factor de insucesso educativo. Por isso, integramos nesta investigao matrias como: uma conceptualizao do multiculturalismo com vista a questionar e clarificar os conceitos e as perspectivas inerentes a este fenmeno. Uma tentativa de desocultar para perceber o contedo simblico e os porqus das polticas de integrao das minorias etnicoculturais que, ao que parece, nos tempos que correm, por quase toda a parte, se converteram numa prioridade absoluta e inadivel. Estabelecemos uma ponte entre a gnese do campo curricular e a construo de um currculo multi e/ou intercultural, merecendo devida ateno as tendncias que dominam as discusses e a produo cientfica actuais nestes domnios. Problematizmos o currculo e identidade na escolaridade obrigatria nas dimenses insero sociocultural, promoo da igualdade de sucesso educativo e incluso dos sujeitos e o currculo e a educao para o exerccio da cidadania numa escola que se quer plural. Neste ltimo debatemos o contedo poltico da educao para a cidadania, as polticas educativas e curriculares e a escolaridade bsica obrigatria como uma proposta que continua em aberto, por isso, passvel de adequao s necessidades de uma educao da e para a diversidade. Procurmos fazer uma anlise das polticas de integrao socioeducativa da diversidade cultural, com destaque para o quadro legal que regula a integrao das minorias tnicas na escola bsica portuguesa, com particular incidncia sobre as crianas pertencentes comunidade caboverdeana nascidas em territrio portugus, procurando concluir acerca da existncia, ou no, de posies e opes de polticas educativas concretas face necessidade de dar prosseguimento educao multicultural neste contexto. Tratou-se de uma investigao qualitativa holstica, que permitiu desenvolver compreenses profundas dos fenmenos a partir das evidncias reunidas, do estudo das representaes dos sujeitos sobre quem recaem os resultados da investigao, mas tambm de sujeitos que, assim como o meio envolvente, estabelecem uma relao indirecta com os mesmos resultados. Circunscrito a um estudo de caso, a reflexo e a partilha de conhecimento e informaes possibilitou desenvolver uma compreenso sobre a problemtica estudada. Dos resultados obtidos, destacmos aqui que, em Portugal, apesar da absorvncia da diversidade cultural nas poltica educativa, no se concretizou, ainda, uma proposta que, na prtica, crie a reciprocidade entre as questes etnicoculturais e o sucesso e/ou insucesso educativos das minorias em educao com ganhos decisivos no combate ao insucesso e ao abandono escolar. Continua-se a desenvolver uma educao igualitarista monocultural pela via da homogeneizao curricular, assente na noo de que povos e grupos podem estar em condies de igualdade se reunidos numa cultura comum. Aparentemente sob pilares democrticos, esta educao multicultural segue a concepo liberal associando essencialismo, universalismo e igualitarismo, resultando num propsito civilizacional excludente das minorias etnicoculturais. As concluses chegadas permitem-nos defender a dessacralizao do currculo nacional comum e uniforme e a defesa de uma proposta curricular baseada numa cultura cientfica global e necessria, de acordo com as faixas etrias e nveis de ensino, com campos de integrao obrigatria de contedos territorializados alicerados no interculturalismo como estratgia promotora da interaco crtica e solidria entre diferentes sujeitos e grupos culturais, permissiva da construo de identidades prprias e da confisso da diferena cultural, associada ao intraculturalismo como uma via permeabilizadora da educao democrtica como garante da cidadania plena a todos os indivduos, como condio fundamental para o estabelecimento das condies de igualdade e de garantia de sucesso em educao.
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Introduction: Prior repeated-sprints (6) has become an interesting method to resolve the debate surrounding the principal factors that limits the oxygen uptake (V'O2) kinetics at the onset of exercise [i.e., muscle O2 delivery (5) or metabolic inertia (3)]. The aim of this study was to compare the effects of two repeated-sprints sets of 6x6s separated by different recovery duration between the sprints on V'O2 and muscular de-oxygenation [HHb] kinetics during a subsequent heavy-intensity exercise. Methods: 10 male subjects performed a 6-min constant-load cycling test (T50) at intensity corresponding to half of the difference between V'O2max and the ventilatory threshold. Then, they performed two repeated-sprints sets of 6x6s all-out separated by different recovery duration between the sprints (S1:30s and S2:3min) followed, after 7-min-recovery, by the T50 (S1T50 and S2T50, respectively). V'O2, [HHb] of the vastus lateralis (VL) and surface electromyography activity [i.e., root-mean-square (RMS) and the median frequency of the power density spectrum (MDF)] from VL and vastus medialis (VM) were recorded throughout T50. Models using a bi-exponential function for the overall T50 and a mono-exponential for the first 90s of T50 were used to define V'O2 and [HHb] kinetics respectively. Results: V'O2 mean value was higher in S1 (2.90.3l.min-1) than in S2 (1.20.3l.min-1); (p<0.001). The peripheral blood flow was increased after sprints as attested by a higher basal heart rate (HRbaseline) (S1T50: +22%; S2T50: +17%; p≤0.008). Time delay [HHb] was shorter for S1T50 and S2T50 than for T50 (-22% for both; p≤0.007) whereas the mean response time of V'O2 was accelerated only after S1 (S1T50: 32.32.5s; S2T50: 34.42.6s; T50: 35.75.4s; p=0.031). There were no significant differences in RMS between the three conditions (p>0.05). MDF of VM was higher during the first 3-min in S1T50 than in T50 (+6%; p≤0.05). Conclusion: The study show that V'O2 kinetics was speeded by prior repeated-sprints with a short (30s) but not a long (3min) inter-sprints-recovery even though the [HHb] kinetics was accelerated and the peripheral blood flow was enhanced after both sprints. S1, inducing a greater PCr depletion (1) and change in the pattern of the fibres recruitment (increase in MDF) compared with S2, may decrease metabolic inertia (2), stimulate the oxidative phosphorylation activation (4) and accelerate V'O2 kinetics at the beginning of the subsequent high-intensity exercise.
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Objetivos: avaluar tasas de respuestas y seguridad, a las 24 semanas del inicio de tratamiento, en pacientes monoinfectados por VHC y coinfectados VIH/VHC con Telaprevir. Mtodos: estudio descriptivo transversal de los pacientes mono y coinfectados (tanto naive, recaedores, no respondedores y respondedores parciales), tratados con Telaprevir en una Unidad de Enfermedades Infecciosas. Se recogieron los datos demogrficos de cada paciente, datos analticos, inmunolgicos y virolgicos as como la determinacin de polimorfismo IL B28. Se recogen datos basales y a las 4, 8, 12 y 24 semanas. Resultados: un total de 43 pacientes analizados que iniciaron tratamiento con Telaprevir. Completan tratamiento hasta 12 semanas los 43, y hasta la semana 24 con Peginterferon y Rivabirina un total de 35 pacientes. Un 48% eran pacientes monoinfectados y un 51% coinfectados VIH-VHC. Un 80% eran hombres y un 20% mujeres, con una edad media de 52 aos +/- 879. A las 12 semanas, un 76% de los pacientes monoinfectados y un 86% de los coinfectados tenan indetectable VHC, y a las 24 semanas un 86% de los monoinfectados y un 90% de los coinfectados, mantenan respuesta viral en tratamiento, sin ser estas diferencias estadsticamente significativas. De la misma forma no se encontraron diferencias estadsticamente significativas en las proporciones de efectos secundarios. Conclusiones: la efectividad y la seguridad del tratamiento con triple terapia que incluye Teleprevir en la infeccin crnica de VHC, son similares en pacientes monoinfectados y coinfectados.
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La ruta sinttica del bis(2-((difenilfosfino)metil)fenil)sulf, Ph2PCH2-(C6H4)S(C6H4)-CH2PPh2 , DPTMephos, involucra 5 reaccions en 4 etapes ben diferenciades. Es per aquest motiu que es fa necessria una optimitzaci de la ruta sinttica per assolir rendiments ms elevats. La primera reacci parteix del sulfur de difenil i involucra la formaci dun complex litiat per acabar realitzant una carbonilaci amb N,N-DMF per obtindre un dialdehid. El segent pas de la ruta passa per la reducci del producte al diol corresponent. Tot seguit ja es por preparar el substrat mitjanjant una bromaci per a que en lltima etapa, sacobli a lestructura el grup difenilfosfino. Tant mateix shan sintetitzat els ismers de la DPTMephos amb [W(CO)6] i [Mo(CO)6], observant-se la formaci tant dels complexos meridionals com facials i la seva interconversi. Tot seguit sha desenvolupat la sulfuraci de la DPTMephos per obtindre els lligands tant mono com di sulfurats. Tamb sha realitzat un estudi de lespectre de RMN 31P{1H} del complex fac-[Mo(CO)3(DPTMephos)] a temperatura variable per determinar el senyal de cada fsfor no equivalent a 200K. Sha realitzat un estudi de forma qualitativa de les conformacions que adopta lanell quelat de 6 baules en les conformacions tant meridional com facial dun complex.
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Este trabalho objetivou investigar as principais unidades estruturais de cidos hmicos obtidos do composto de resduos slidos urbano (AH-CRSU) e lodo de estao de tratamento de esgoto (AH-LETE) por meio da pirlise acoplada cromatografia gasosa / espectrometria de massas. Os cidos hmicos extrados do lodo da estao de tratamento de esgotos apresentaram maior quantidade de mono e diaril steres de massa mais elevada. Os n-alcanos presentes nos AH-LETE revelaram-se de cadeia mais curta do que nos AH-CRSU. Foram incorporados na estrutura dos AH fragmentos de ftalatos, provavelmente em virtude da contaminao da matria orgnica por plsticos. Os compostos aromticos presentes nos AH-LETE originaram-se, principalmente, de derivados do naftaleno e derivados do benzeno com substituio por cadeias alifticas maiores do que AH-CRSU. Os compostos nitrogenados presentes mostraram-se essencialmente heteroaromticos e os oxigenados furanos substitudos originados da degradao de carboidratos. Os compostos oxiaromticos predominantes foram fenis substitudos.
Resumo:
The HbpR protein is the sigma54-dependent transcription activator for 2-hydroxybiphenyl degradation in Pseudomonas azelaica. The ability of HbpR and XylR, which share 35% amino acid sequence identity, to cross-activate the PhbpC and Pu promoters was investigated by determining HbpR- or XylR-mediated luciferase expression and by DNA binding assays. XylR measurably activated the PhbpC promoter in the presence of the effector m-xylene, both in Escherichia coli and Pseudomonas putida. HbpR weakly stimulated the Pu promoter in E. coli but not in P. azelaica. Poor HbpR-dependent activation from Pu was caused by a weak binding to the operator region. To create promoters efficiently activated by both regulators, the HbpR binding sites on PhbpC were gradually changed into the XylR binding sites of Pu by site-directed mutagenesis. Inducible luciferase expression from mutated promoters was tested in E. coli on a two plasmid system, and from mono copy gene fusions in P. azelaica and P. putida. Some mutants were efficiently activated by both HbpR and XylR, showing that promoters can be created which are permissive for both regulators. Others achieved a higher XylR-dependent transcription than from Pu itself. Mutants were also obtained which displayed a tenfold lower uninduced expression level by HbpR than the wild-type PhbpC, while keeping the same maximal induction level. On the basis of these results, a dual-responsive bioreporter strain of P. azelaica was created, containing both XylR and HbpR, and activating luciferase expression from the same single promoter independently with m-xylene and 2-hydroxybiphenyl.
