165 resultados para Tetrabromoazamenzimodazol (TBB)


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O gênero Leishmania apresenta espécies capazes de desenvolver doenças de grande importância para a saúde pública, as leishmanioses, que apresentam prevalência mundial de 12 milhões de pessoas. Quando os parasitos entram em contato com o hospedeiro humano passam por um processo de metaciclogênese adquirindo capacidade de interagir com os macrófagos. Inúmeras atividades biológicas são desencadeadas pela ativação de sistemas de transdução de sinais, onde as proteínas cinases e fosfatases desempenham papel fundamental. A proteína cinase CK2 parece estar presente em todas as células eucarióticas (núcleo, citoplasma e superfície). É caracterizada como enzima serina/treonina cinase, embora também seja capaz de fosforilar resíduos de tirosina em suas proteínas-alvo. No presente trabalho, demonstramos que o principal inibidor da CK2, TBB, foi capaz de inibir o crescimento de formas promastigotas de L. donovani e mostrou um mecanismo de ação irreversível, entretanto não foi capaz de induzir apoptose nas formas promastigotas de L. donovani. O pré-tratamento dos parasitos e macrófagos, assim como a adição do TBB durante o processo de infecção induziram uma redução significativa no número de amastigotas por macrófagos possivelmente pelo mecanismo de morte celular programada demosntrada pela técnica do TUNEL. O tratamento de macrófagos com TBB não induziram o aumento de óxido nítrico. Ensaios de imunofluorescência demonstraram a presença de CK2α em promastigotas. Macrófagos não infectados demonstraram pouca marcação para CK2α. Após a interação, a enzima mostrou-se distribuída preferencialmente na periferia dos macrófagos. Os dados do trabalho sugerem que a CK2 é uma importante enzima para a atividade biológica da Leishmania donovani, tendo seu estudo importante relevância para a descoberta de novos alvos terapêuticos.

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Műhelytanulmányunk fő célja a gazdasági világválság termelésre gyakorolt hatásainak bemutatása a versenyképesség kutatás adatainak elemzésével. Mivel a vállalatokra a válság különbözőképpen hat, ezért érintettségük alapján három csoportba soroltuk őket. Az irodalom felhasználásával megfogalmaztuk a termelési stratégiára és a termelés működési következményeire vonatkozó hipotéziseinket. Eredményeink alapján a válsággal leginkább érintett vállalatok rendelkeznek a legstabilabb termelési stratégiával és gyakorlattal. Ugyanakkor a válság következtében az ár és a szolgáltatások stratégiai szerepe minden vállalatnál erősödött, az innovációé viszont visszaesett. A gyakorlatok szintjén a válság egyik vállalatcsoportnál sem eredményezte a megmaradó munkaerő fejlesztésének ugrásszerű növekedését. A folyamatfejlesztés erősödése, illetve a globális irányba mozdulás csak a legkevésbé érintett csoportnál volt jellemző. Eredményeink alapján a válság általi érintettség és a termelési stratégia, illetve gyakorlat területén bekövetkezett hangsúlyeltolódások között nem nagyon van összefüggés. ________ The objective of this study is to describe the impact of the world economic crisis on operations using the data of the competitiveness survey. Since the crisis affects companies differently, we classified them into three groups: the most affected, the moderately affected and the least affected group, accordingly. Relying on the literature we formed hypotheses about the impact of crisis on operations strategy and its everyday operational consequences. Based on our results the most affected companies have the most stable operations strategy and practices. Nevertheless, due to the crisis the importance of prices and services increased, while the importance of innovation decreased in each group. At the level of everyday practice the crisis has not led to extraordinary increase in work force development. Process improvement and turning to globalization became stronger only in the least affected group. According to our results, there is no direct link between the perceived impact of crisis and the changes in operations strategies and practices.

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A fenntarthatóság értékelése definíciószerűen többdimenziós probléma. A megfelelő alternatíva, forgatókönyv, eljárás stb. kiválasztásakor ugyanis a döntéshozóknak egyszerre kell figyelembe venniük környezetvédelmi, gazdasági és társadalmi szempontokat. Az ilyen döntéseket alátámaszthatják a több szempontú döntéshozatali modellek. A tanulmány a több szempontú döntési eljárások közül a legfontosabb hétnek az alkalmazhatóságát vizsgálja részvételi körülmények között. Az utóbbi évek e témában publikált esettanulmányainak áttekintésével megállapítható, hogy egyik módszer sem uralja a többit, azok különböző feltételek mellett eltérő sikerrel használhatók. Ennek ellenére a különböző módszerek kombinációjával végrehajthatunk olyan eljárásokat, amelyekkel az egyes módszerek előnyeit még jobban kiaknázhatjuk. ________ Measuring and comparing the sustainability of certain actions, scenarios, technologies, etc. is by definition a multidimensional problem. Decision-makers must consider environmental, economic and social aspects when choosing an alternative course of action. Such decisions can be aided by multi-criteria decision analysis (MCDA). This paper investigates seven different MCDA methodologies: MAU, the Analytic Hierarchic Process (AHP), the ELECTRE, PROMETHEE, REGIME, and NAIADE methods, and "Ideal and reference point" approaches). It is based on a series of reports in which over 30 real-world case studies focusing on participatory MCDA were reviewed. It is stressed, however, that there is no "best" choice in the list of MCDA techniques. Some methods fit certain decision problems better than others. Nonetheless, some complementary benefits of the different techniques can be exploited by combining these methodologies.

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A tanulmány azt a kérdést vizsgálja egy duopólium modellben, hogy egy termelőnek érdemes-e lényegében ugyanazt a terméket több formában, differenciáltan piacra dobnia. A modell ebben a csupasz formájában csak igen korlátozott mértékben épít a játékosok közti interakciókra, egy egyszer˝u szimultán döntési folyamatot ábrázol, azt is statikus környezetben. Az elemzés azt mutatja, hogy a keresleti paraméterek bizonyos értékei mellett még akkor is érdemes új, az eddigiektől eltérő tulajdonságú, differenciált termék piacra vitele, ha annak ára nem tér el a már korábban bevezetett terméktől, és így annál önmagában nem tekinthet˝o nagyobb nyereséget biztosítónak. Az a tény, hogy egy vállalat több differenciált termékvariánst árusít, arra vezet, hogy a korábbi egyensúlyi helyzethez képest kedvezőbb pozícióba kerül, mint a versenytársa.

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A marketingkutatás területét – más üzleti területekhez hasonlóan – markánsan érintik az elmúlt időszak társadalmi-gazdasági változásai. A kutatásmódszertan ennek megfelelően változik és ez a változás részben azt is jelenti, hogy a korábbi éles határok egyes módszertani területek között, úgymint a kvalitatív és kvantitatív megközelítések, elhalványulnak. Jelen tanulmány a több-módszertanú és vegyes módszertanú kutatásokat vizsgálja, illetve értelmezi ezeket az aktuális kutatás-módszertani trendek kapcsán.

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Candidatus Phytoplasma australiense (Ca. P. australiense) is associated with the plant diseases strawberry lethal yellows (SLY), strawberry green petal (SGP), papaya dieback (PDB), Australian grapevine yellows (AGY) and Phormium yellow leaf (PYL; New Zealand). Strawberry lethal yellows disease is also associated with a rickettsia-like-organism (RLO) or infrequently with the tomato big bud (TBB) phytoplasma, the latter being associated with a wide range of plant diseases throughout Australia. In contrast, the RLO has been identified only in association with SLY disease, and Ca. P. australiense has been detected only in a limited number of plant host species. The aim of this study was to identify plant hosts that are possible reservoirs of Ca. P. australiense and the SLY RLO. Thirty-one plant species from south-east Queensland were observed with disease between 2001 and 2003 and, of these, 18 species tested positive using phytoplasma-specific primers. The RLO was detected in diseased Jacksonia scoparia and Modiola caroliniana samples collected at Stanthorpe. The TBB phytoplasma was detected in 16 different plant species and Ca. P. australiense Australian grapevine yellows strain was detected in six species. The TBB phytoplasma was detected in plants collected at Nambour, Stanthorpe, Warwick and Brisbane. Ca. P. australiense was detected in plants collected at Nambour, Stanthorpe, Gatton and Allora. All four phytoplasmas were detected in diseased Gomphocarpus physocarpus plants collected at Toowoomba, Allora, Nambour and Gatton. These results indicated that the vector(s) of Ca. P. australiense are distributed throughout south-east Queensland and the diversity of phytoplasmas detected in G. physocarpus suggests it is a feeding source for phytoplasma insect vectors or it has a broad susceptibility to a range of phytoplasmas.

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A paradigm shift from hard to flexible, organic-based optoelectronics requires fast and reversible mechanical response from actuating materials that are used for conversion of heat or light into mechanical motion. As the limits in the response times of polymer-based actuating materials are reached, which are inherent to the less-than-optimal coupling between the light/heat and mechanical energy in them, 1 a conceptually new approach to mechanical actuation is required to leapfrog the performance of organic actuators. Herein, we explore single crystals of 1,2,4,5-tetrabromobenzene (TBB) as actuating elements and establish relations between their kinematic profile and mechanical properties. Centimeter-size acicular crystals of TBB are the only naturally twinned crystals out of about a dozen known materials that exhibit the thermosalient effect-an extremely rare and visually impressive crystal locomotion. When taken over a phase transition, crystals of this material store mechanical strain and are rapidly self-actuated to sudden jumps to release the internal strain, leaping up to several centimeters. To establish the structural basis for this colossal crystal motility, we investigated the mechanical profile of the crystals from macroscale, in response to externally induced deformation under microscope, to nanoscale, by using nanoindentation. Kinematic analysis based on high-speed recordings of over 200 twinned TBB crystals exposed to directional or nondirectional heating unraveled that the crystal locomotion is a kinematically complex phenomenon that includes at least six kinematic effects. The nanoscale tests confirm the highly elastic nature, with an elastic deformation recovery (60%) that is far superior to those of molecular crystals reported earlier. This property appears to be critical for accumulation of stress required for crystal jumping. Twinned crystals of TBB exposed to moderate directional heating behave as all-organic analogue of a bimetallic `strip, where the lattice misfit between the two crystal components drives reveriible deformation of the crystal.

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O gênero Leishmania é responsável por um grupo de parasitoses que podem variar desde lesões auto-limitadas até severa injúria de tecido. Estes protozoários são parasitos obrigatoriamente intracelulares, tendo o macrófago como célula hospedeira. Durante o processo de fagocitose os macrófagos utilizam a maquinaria presente em seu citoesqueleto, a qual compreende a participação de miosinas e actinas, para a formação do fagossoma. Estas proteínas estão envolvidas em processos como citocinese, tráfego intracelular de organelas e vesículas, podendo interferir com a penetração do parasito. Alguns trabalhos vêm sendo realizados visando analisar a expressão, localização e o papel de miosina e de actina em Leishamania. Estudos associados à participação destas proteínas motoras em processo vitais para a biologia do parasito podem auxiliar na compreensão de seu ciclo e permitir a geração de conhecimentos que apontem novos alvos para intervenções terapêuticas. Uma vez que a miosina é necessária no transporte intracelular, alguns estudos tentam analisar a expressão e a localização intracelular de miosinas na Leishmania. Estudos mostram a presença de atividades cinásicas do tipo CK2 em diversos tripanossomatídeos, ligadas ao crescimento celular, morfologia e infectividade de promastigotas para macrófagos. Desta maneira, como objetivo desta tese temos o estudo da participação das miosinas, actina e CK2 na infectividade da Leishmania braziliensis. Além disso, investigamos a influência destas proteínas na produção de citocinas pelos macrófagos e em sua atividade microbicida. Lipoxina, latrunculina, nocodazol e TBB promoveram uma inibição de, pelo menos, 50% no crescimento de L. braziliensis. A CK2 secretada pelo parasito foi purificada de seu sobrenadante através de coluna de HPLC e a fração 44 mostrou ser a fração correspondente a esta enzima. A lipoxina e o TBB promoveram a inibição da atividade desta enzima ao contrário da latrunculina que forneceu aumento dessa atividade. O pré-tratamento dos parasitos ou dos macrófagos com lipoxina, latrunculina, nocodazol e TBB promoveram uma inibição de cerca de 50% no índice de associação entre Leishmania e macrófagos não-ativados ou ativados por LPS e IFN-γ. Latrunculina e TBB aumentaram a produção de NO em macrófagos não ativados e não infectados enquanto que em macrófagos ativados à exceção do TBB, todas as drogas diminuíram a produção de NO. A liberação de IL-10 foi diminuída após tratamento com todas as drogas em macrófagos não ativados em ausência de promastigotas e ativados em presença do parasito. Para a produção de TNF-α há uma redução significativa em macrófagos ativados não infectados tratados com latrunculina, nocodazol e TBB. Quando ativados e infectados, os macrófagos tratados com lipoxina tiveram a produção dessa citocina aumentada, ao contrário do TBB em que houve redução. Quando avaliamos a integridade da actina verificamos que todos os compostos foram capazes de influenciar a distribuição dessa proteína, levando a uma redução no índice de associação. Ao transfectarmos a cauda da miosina Va fusionada a GFP nos macrófagos observamos que houve uma diminuição de 94% no índice de associação. Nossos dados confirmam a importância da CK2, actina e miosina Va no processo de interação parasito- macrófago.

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Arsenic is accumulated by free-living small mammals, but there is little information on the resultant concentrations in different tissues other than liver and kidney. Such information is important because the severity of toxicological effects may be related to the amount of arsenic accumulated in specific organs, and the availability of arsenic to predators is, in part, dependent on which tissues accumulate arsenic. The objective of this study was to quantify the arsenic concentrations and the percentage of the total body burden (%TBB) accumulated in different body tissues of free-living small mammals and to determine how these factors varied with severity of habitat contamination. Arsenic concentrations were measured in various tissues of wood mice (Apodemus sylvaticus) and bank voles (Clethrionomys glareolus) from a range of arsenic-contaminated sites in southwest Britain. Arsenic concentrations in the gastrointestinal (GI) tract (including contents), liver, kidneys, spleen, lung, femur, and fur of both species varied significantly between sites and were higher in mice and voles from heavily contaminated areas. Heart and brain arsenic concentrations did not vary with degree of environmental contamination. The GI tract and excised carcass contained roughly equal amounts of arsenic and, in sum, comprised 75-85% of the TBB on uncontaminated sites and 90-99% on contaminated sites. Although the excised carcass contains about half of the TBB, its importance in food-chain transfer of arsenic to predators may depend on the bioavailability of arsenic sequestered in fur. In contrast, the GI tract and its contents, provided that it is consumed, will always be a major transfer pathway for arsenic to predators, regardless of the severity of habitat contamination.

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The pine wood nematode Bursaphelenchus xylophilus reproduces bisexually: a haploid sperm fertilizes a haploid oocyte, and the two pronuclei rearrange, move together, fuse, and begin diploid development. Early embryonic events taking place in the B. xylophilus embryo are similar to those of Caenorhabditis elegans, although the anterior-posterior axis appeares to be determined oppositely to that observed for C. elegans. Thai is, in the B. xylophilus embryo, the male pronucleus emerges at the future anterior end, whereas the female pronucleus appeares laterally. To understand the evolution of nematode developmental systems, we cloned the full length of Bx-tbb-1 (beta tubulin) from B. xylophilus cDNA and attempted to apply reverse genetics analysis to B. xylophilus. Several lengths of double stranded RNA (dsRNA) for the Bx-tbb-1 gene were synthesized by in vitro transcription, and both B. xylophilus and C. elegans were soaked in dsRNA for RNAi. Both nematodes could suck up the dsRNA, and we could detect the abnormal phenotypes caused by Bx-tbb-1 dsRNA in C. elegans, but not in B. xylophilus. We suspect that systemic RNAi might be suppressed in B. xylophilus and are attempting to establish other methods for functionally analyzing B. xylophilus genes.

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La transplantation pulmonaire pour les patients avec une maladie pulmonaire en phase terminale est leur seul espoir de survie. Malheureusement, certains greffés du poumon rencontrent des difficultés après la transplantation du poumon, dont l'un est le rejet chronique du greffon pulmonaire également connu histologiquement comme la bronchiolite oblitérante et cliniquement comme syndrome de bronchiolite oblitérante. L'étiologie exacte de la BO reste mal comprise. Certaines hypothèses suggèrent l'implication des cellules épithéliales dans le processus de remodelage des voies respiratoires, conduisant à l'obstruction des voies aériennes. Un des mécanismes proposés est un processus de transition, connue sous le nom de transition épithéliale-mésenchymateuse (TEM). Lors de ce processus, les cellules perdent leurs propriétés épithéliales, acquièrent un phénotype mésenchymateux et deviennent plus mobiles et envahissantes. Cette transformation leur permet de participer activement au processus de remodelage bronchique dans la bronchiolite oblitérante. L’induction de la TEM peut être due à certains facteurs tels que l'inflammation et l'apoptose. Le principal objectif de ce travail de maîtrise est de détecter in vivo la présence de la TEM dans des biopsies transbronchiques obtenues chez des greffés et de l’associer à leurs conditions cliniques. Le deuxième objectif est d'induire la TEM in vitro dans les cellules épithéliales des petites voies aériennes à l'aide de milieux conditionnés apoptotiques et non apoptotiques produits par les cellules endothéliales microvasculaires humaines du poumon. D’autre part, nous avons évalué si des médiateurs connus pour participer au processus de TEM tels que le facteur de croissance du tissu conjonctif (CTGF)et le facteur de croissance transformant bêta (TGF-beta) ainsi que le perlecan sont présents dans les milieux conditionnés utilisés.

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In this study, the extraction properties of a synergistic system consisting of 2,6-bis-(benzoxazolyl)-4-dodecyloxylpyridine (BODO) and 2-bromodecanoic acid (HA) in tert-butyl benzene (TBB) have been investigated as a function of ionic strength by varying the nitrate ion and perchlorate ion concentrations. The influence of the hydrogen ion concentration has also been investigated. Distribution ratios between 0.03-12 and 0.003-0.8 have been found for Am(III) and Eu(HI), respectively, but there were no attempts to maximize these values. It has been shown that the distribution ratios decrease with increasing amounts of ClO4-, NO3-, and H+. The mechanisms, however, by which the decrease occurs, are different. In the case of increasing perchlorate ion concentration, the decrease in extraction is linear in a log-log plot of the distribution ratio vs. the ionic strength, while in the nitrate case the complexation between nitrate and Am or Eu increases at high nitrate ion concentrations and thereby decreases the distribution ratio in a non-linearway. The decrease in extraction could be caused by changes in activity coefficients that can be explained with specific ion interaction theory (SIT); shielding of the metal ions, and by nitrate complexation with Am and Eu as competing mechanism at high ionic strengths. The separation factor between Am and Eu reaches a maximum at similar to1 M nitrate ion concentration. Thereafter the values decrease with increasing nitrate ion concentrations.

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OBJETIVO: Estudar os padrões clínicos, radiológicos e histopatológicos da biópsia transbrônquica (BTB) utilizados para a confirmação diagnóstica em pacientes com suspeita clinica de doença pulmonar intersticial (DPI) atendidos em um hospital universitário de nível terciário. MÉTODOS: Os prontuários, laudos radiológicos e de biópsias transbrônquicas de todos os pacientes com suspeita de DPI submetidos a BTB entre janeiro de 1999 e dezembro de 2006 no Hospital das Clínicas de Botucatu, localizado na cidade de Botucatu (SP), foram revisados. RESULTADOS: Foram incluídos no estudo 56 pacientes. Desses, 11 (19,6%) apresentaram o diagnóstico definitivo de fibrose pulmonar idiopática (FPI), que foi significativamente maior nos casos nos quais DPI era uma possibilidade diagnóstica em comparação com aqueles nos quais DPI era a principal suspeita (p = 0,011), demonstrando a contribuição da BTB para a definição diagnóstica dessas doenças. O exame histopatológico dessas biópsias revelou que 27,3% dos pacientes com FPI apresentavam o padrão de pneumonia organizante, o que pode sugerir doença mais avançada. O padrão histológico indeterminado foi o mais frequente, refletindo a característica periférica da FPI. Entretanto, o padrão fibrose apresentou alta especificidade e alto valor preditivo negativo. Para os padrões sugestivos de FPI em TC, a curva ROC indicou que a melhor relação entre sensibilidade e especificidade ocorreu com a presença de cinco alterações radiológicas, sendo o aspecto de favo de mel fortemente sugestivo de FPI (p = 0,01). CONCLUSÕES: Nas DPIs, a TC de tórax deve ser sempre realizada e a BTB usada em situações individualizadas, conforme a suspeita e distribuição das lesões.

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Pós-graduação em Química - IQ

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Objective: To evaluate the diagnostic accuracy of bronchoscopy in patients with clinical or radiological suspicion of tuberculosis who were unable to produce sputum or with negative sputum smear microscopy results. Methods: A prospective cross-sectional study involving 286 patients under clinical or radiological suspicion of having pulmonary tuberculosis and submitted to bronchoscopy-BAL and transbronchial biopsy (TBB). The BAL specimens were submitted to direct testing and culture for AFB and fungi, whereas the TBB specimens were submitted to histopathological examination. Results: Of the 286 patients studied, 225 (79%) were diagnosed on the basis of bronchoscopic findings, as follows: pulmonary tuberculosis, in 127 (44%); nonspecific chronic inflammation, in 51 (18%); pneumocystis, fungal infections, or nocardiosis, in 20 (7%); bronchiolitis obliterans organizing pneumonia, alveolites, or pneumoconiosis, in 14 (5%); lung or metastatic neoplasms, in 7 (2%); and nontuberculous mycobacterium infections, in 6 (2%). For the diagnosis of tuberculosis, BAL showed a sensitivity and a specificity of 60% and 100%, respectively. Adding the TBB findings significantly increased this sensitivity (to 84%), as did adding the post-bronchoscopy sputum smear microscopy results (total sensitivity, 94%). Minor post-procedure complications occurred in 5.6% of the cases. Conclusions: Bronchoscopy is a reliable method for the diagnosis of pulmonary tuberculosis, with low complication rates. The combination of TBB and BAL increases the sensitivity of the method and facilitates the differential diagnosis with other diseases.