947 resultados para COMPOUND-I FORMATION


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In trypanosomatids the involvement of mitochondrial complex I in NADH oxidation has long been debated. Here, we took advantage of natural Trypanosoma cruzi mutants which present conspicuous deletions in ND4, ND5 and ND7 genes coding for complex I subunits to further investigate its functionality. Mitochondrial bioenergetics of wild type and complex I mutants showed no significant differences in oxygen consumption or respiratory control ratios in the presence of NADH-linked substrates or FADH(2)-generating succinate. No correlation could be established between mitochondrial membrane potentials and ND deletions. Since release of reactive oxygen species occurs at complex I, we measured mitochondrial H(2)O(2) formation induced by different substrates. Significant differences not associated to ND deletions were observed among the parasite isolates, demonstrating that these mutations are not important for the control of oxidant production. Our data support the notion that complex I has a limited function in T. cruzi.

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The phytopathogen Xylella fastidiosa produces long type IV pili and short type I pili involved in motility and adhesion. In this work, we have investigated the role of sigma factor sigma(54) (RpoN) in the regulation of fimbrial biogenesis in X. fastidiosa. An rpoN null mutant was constructed from the non-pathogenic citrus strain J1a12, and microarray analyses of global gene expression comparing the wild type and rpoN mutant strains showed few genes exhibiting differential expression. In particular, gene pilA1 (XF2542), which encodes the structural pilin protein of type IV pili, showed decreased expression in the rpoN mutant, whereas two-fold higher expression of an operon encoding proteins of type I pili was detected, as confirmed by quantitative RT-PCR (qRT-PCR) analysis. The transcriptional start site of pilA1 was determined by primer extension, downstream of a sigma(54)-dependent promoter. Microarray and qRT-PCR data demonstrated that expression of only one of the five pilA paralogues, pilA1, was significantly reduced in the rpoN mutant. The rpoN mutant made more biofilm than the wild type strain and presented a cell-cell aggregative phenotype. These results indicate that sigma(54) differentially regulates genes involved in type IV and type I fimbrial biogenesis, and is involved in biofilm formation in X. fastidiosa.

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In the xylem vessels of susceptible hosts, such as citrus trees, Xylella fastidiosa forms biofilm-like colonies that can block water transport, which appears to correlate to disease symptoms. Besides aiding host colonization, bacterial biofilms play an important role in resistance against antimicrobial agents, for instance antimicrobial peptides (AMPs). Here, we show that gomesin, a potent AMP from a tarantula spider, modulates X. fastidiosa gene expression profile upon 60 min of treatment with a sublethal concentration. DNA microarray hybridizations revealed that among the upregulated coding sequences, some are related to biofilm production. In addition, we show that the biofilm formed by gomesin-treated bacteria is thicker than that formed by nontreated cells or cells exposed to streptomycin. We have also observed that the treatment of X. fastidiosa with a sublethal concentration of gomesin before inoculation in tobacco plants correlates with a reduction in foliar symptoms, an effect possibly due to the trapping of bacterial cells to fewer xylem vessels, given the enhancement in biofilm production. These results warrant further investigation of how X. fastidiosa would respond to the AMPs produced by citrus endophytes and by the insect vector, leading to a better understanding of the mechanism of action of these molecules on bacterial virulence.

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The reaction Of Cu(ClO(4))(2)center dot 6H(2)O with dimethylglyoxime (H(2)dmg) in a 1:1 mole ratio in aqueous methanol at room temperature affords the dinuclear complex [Cu(2)(mu-Hdmg)(4)] (1). Reaction of 1 with [Cu(bpy)(H(2)O)(2)](ClO(4))(2) (bpy = 2,2`-bipyridine) in a 1:1 mole ratio in aqueous methanol at room temperature yields the tetranuclear complex [Cu(2)(mu-HdMg)(2)(mu-dMg)(2)(bpy)(2)(H(2)O)(2)](ClO(4))(2) (2). The direct reaction of Cu(ClO(4))(2)center dot 6H(2)O with H(2)dmg and bpy in a 2:21 mole ratio in aqueous methanol at room temperature also yields 2 quantitatively. The complexes 1 and 2 were structurally characterized by X-ray crystallography. Unlike the binding in Ni/Co-dmg, two different types of N-O bridging modes during the oxime based metallacycle formation and stacking of square planar units have been identified in these complexes. The neutral dinuclear complex 1 has CuN(4)O coordination spheres and complex 2 consists of a dicationic [Cu(2)(mu-HdMg)(2)(mu-dMg)(2)(bpy)(2)(H(2)O)(2)](2+) unit and two uncoordinated ClO(4)(-) anions having CuN(4)O and CuN(2)O(3) coordination spheres. The two copper(II) ions are at a distance of 3.846(8) angstrom in 1 for the trans out of plane link and at 3.419(10) and 3.684(10) angstrom in 2 for the trans out of plane and cis in plane arrangements, respectively. The average Cu-N(oxime) distances are 1.953 and 1.935 angstrom, respectively. The average basal and apical Cu-N(oxime) distances are 1.945, 2.295 and 2.429 angstrom. The UV-Vis spectra of 2 is similar to the spectrum of the reaction mixture of 1 and [Cu(bpy)(H(2)O)(2)](2+). Variable temperature magnetic properties measurement shows that the interaction between the paramagnetic copper centers in complex I is antiferromagnetic in nature. The EPR spectra of frozen solution of the complexes at 77 K consist of axially symmetric fine-structure transitions (Delta M(S) = 1) and half-field signals (Delta M(S) = 2) at ca. 1600 G, suggesting the presence of appreciable Cu-Cu interactions. (C) 2009 Elsevier Ltd. All rights reserved.

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Photochemical and photophysical properties of fac-[Re(CO)(3)(Clphen)(trans-L)](+) complexes, Clphen = 5-chloro-1,10-phenathroline and L = 1,2-bis(4-pyridyl)ethylene, bpe, or 4-styrylpyridine, stpy, were investigated to complement the understanding of intramolecular energy transfer process in tricarbonyl rhenium(I) complexes having an electron withdrawing group attached to polypyridyl ligands. These new compounds were synthesized, characterized and the photoisomerization quantum yields were accurately determined by (1)H NMR spectroscopy. The true quantum yields for fac-[Re(CO)(3)(Clphen) (trans-bpe)](+) were constant (Phi = 0.55) at all investigated irradiation wavelengths. However, for fac-[Re(CO)(3)(Clphen)(trans-stpy)](+), similar true quantum yields were observed only at higher energy irradiation (Phi(313 nm) = 0.53 and Phi(365 nm) = 0.57), but it decreased significantly at 404 nm (Phi = 0.41). These results indicated different deactivation pathways for the trans-stpy complex photoisomerization. Quantum yields decreased as the (3)IL(trans-L) and (3)MLCT(Re -> NN) excited states become closer and the behavior was discussed in terms of the excited state energy gaps. Additionally, luminescence properties of photoproducts, fac-[Re(CO)(3)(Clphen)(cis-L)](+), were also investigated in different environments to analyze the relative energy of the (3)MLCT(Re -> Clphen) excited state for each compound. (C) 2011 Elsevier B.V. All rights reserved.

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In this work, a series of 10 structural procaine analogs have been synthesized in order to investigate the structural features affecting the stability of ion pair formation and its influence on the lipophilicity of ionizable compounds. The structural variation within this series was focused on the terminal nitrogen substituents and on the intermediate chain linkage nature. The hydrophobic parameters log P(n) and log P(i) (partition coefficient of the neutral and ionic species, respectively), as well as the ionization constants pK(a) and pK(a)(oct), were obtained from log D-pH profiles measured at pH values ranging from 2 to 12. The difference between log P(i) and log P(n) values (i.e. difflog P) of each prepared compound was considered a measure of the stability of ion pair formation. In this set, the difflog P values varied nearly over one log unit, ranging from -2.40 to -3.37. It has been observed that the presence of hydrogen bonding groups (especially donor) and low steric hindrance around the terminal amine ionizable group increases the relative lipophilicity of the ionic species as compared to the corresponding neutral species. These results were interpreted as due to the increased stability of ion pairs of the compounds bearing these structural features. (C) 2010 Elsevier B.V. All rights reserved.

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The aim of this study is to elucidate factors that effect growth of Sarcina lutea and Bacillus subtilis, exposed to the growth inhibitor SDS (Sodiumdodecylsulfat). Agar diffusion experiments revealed repeated, concentric zones of inhibition and stimulation upon exposure to Sodiumdodecylsulphate or to Amoxicillin. Temperature, nutrient concentration and inhibitor concentration were controlled. Formation of successively repeated zones of inhibition, stimulation, inhibition and stimulation is discussed: •The extension of the primary inhibition zone is due to the concentration of applied Sodium dodecyl sulphate.•Immediately outside the primary inhibition zone the bacteria have access to diffusing nutrients that have not been consumed in the primary inhabitation zone.•In zones of dense bacterial growth the bacteria may produce inhibiting substances, affecting growth of bacteria in adjacent zones.•In zones of dense bacterial growth the nutrients will soon become depleted, thus affecting bacteria in adjacent zones.

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Syftet med föreliggande systematiska litteraturstudie var att beskriva kvinnors behov av in-formation i samband med hysterektomi. Via Högskolan Dalarnas databas Elin och Blackwell Synergy söktes vetenskapliga fulltextartiklar som behandlade kvinnors informationsbehov vid livmoderoperation. Av 41 artiklar valdes 15 ut varav 8 kvantitativa och 7 kvalitativa. Dessa kvalitetsprövades med 28 kriterier från modifierade granskningsmallar efter Forsberg och Wengström (2003) samt Willman, Stoltz och Bahtsevani (2006). Av artikelurvalet framkom att kvinnorna saknade information om hysterektomi i allmänhet och i synnerhet om behand-lingsalternativ samt kvinnans gynekologiska hälsa och dessutom om post-operativ sexualitet. Informationen hade betydelse för kvinnans återhämtning och välmående efter ingreppet. Den-na studie ökar vårdpersonalens förståelse för kvinnans behov av information om hysterektomi så att hon kan vara delaktig i beslutet rörande den egna kroppen.

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In schools today, we expect student performances and achievements to be exceptional. Having good reading and writing skills are essential if students want to excel at their school assignments. Students with reading and writing difficulties have to work much harder than their other classmates. Their having to work harder coupled with being teenagers and facing all the uncertainties which are present at that age, these students face the difficult task of trying to find out who they are and who they want to be. In other words, they try to create their own individual identities. This study investigates the experiences of students with reading and writing difficulties in their interactions with other students and school personnel, in different situations. The collection of data has been done through group interviews. Thirteen, 15 year old students participated in these interviews. Some of the factors which characterise a hermeneutic approach have helped to form the basis on which the study lies. A hermeneutic approach suggests that the data collected is sorted and analysed to enable the identification of differences and patterns. These patterns are arranged to give results that are subjective and which also show an interpretation of the data collected. The results show that students are more comfortable with their identities, when they are diagnosed or made aware that their performances in school are directly affected by their reading and writing difficulties. The study also shows that having reading and writing difficulties tells the students who they are but, at the same time, plays an important role in their interactions with other classmates and adults. The outcomes of these interactions greatly affect the formation of their identities. The way in which school personnel treat students is also shown to be of great importance.

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This degree project aim to evaluate if variations of the STFI thickness can be used to assess bumpiness on cardboard. During the project cardboard samples were measured using Bendtsen, PPS, a L&W formation tester, OptiTopo, Ambertec formation, the STFI thickness tester and a visual comparison. The different methods were then compared to see if there is any correlations between them. The results showed that the visual comparison and OptiTopo correlates. The STFI thickness tester shows however no correlation with the OptiTopo and visual comparison, thus aren't suitable measuring bumpiness.

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The purpose of this work was to determine how important a word’s setting was for the readability of typography in motion. Facts regarding how reading works and the importance of the words formation for the readability were used to form a computer test. This test was performed by 15 test persons and the results were analyzed. The results show that the serif was easier to read than the sanserif. The words of the serif which were easiest to read were the words with positive tracking and the words with capital letters. Also for the sanserif, these words were the easiest to read.

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Föreliggande vårdvetenskapliga studie har som syfte att avtäcka och synliggöra glädjesom idé i vårdandets värld. Glädje sammanbinds med vårdandet genom kärleken somden tongivande kraften hos glädje. Vårdandets sak har genom historien alltid varit attlindra lidande och att tjäna liv och hälsa i en anda av kärlek och barmhärtighet. Dennastudie om glädje i vårdandet har en övergripande idéhistorisk inriktning och resultatetsammanställs i form av ett idémönster. Tolkningen sker genom en hermeneutisk ansatsmed fokus på förståelse av själva vårdandet. För att djupare förstå glädje, dessursprungsidé, väsen och uttrycksformer granskas begreppet ’glädje’ och de näraliggandebegreppen ’glad’ och ’ljus’ i etymologiska ordböcker samt i svenska, engelska ochlatinska ordböcker. Som stöd för tolkningen används klassiska texter innehållandefilosofers tankar om glädje. Glädje som idé glimtar fram i form av ett sjufaldigtmönster. Detta mönster innehåller särdrag hos glädje och det hjärtas natur somrespektive särdrag förverkligas i. I andlig mening utgör hjärtat livets medelpunkt ochkänslornas hemvist. Mönstret bildar bakgrund och blir vägledande vid den hermeneutiska läsningen omglädje, så som den framträder i berättelser om vårdande under åren 1900–1933. Dehistoriska källorna utgörs av facktidskriften Svensk sjukskötersketidning, böcker medberättelser om vårdande, arkivmaterial samt läroböcker om vårdarbete. Resultatetmynnar ut i ett idémönster, där idéer om det som gör glädje verksamt som vårdandeframträder. Dessa är det sanna hjärtats rena glädje – kärlek, glädje är ett kärleksbevis.Det brinnande hjärtats djupa glädje – livsglädje, glädje inspirerar och genererar kraft.Det bärande hjärtats glansfulla glädje – generositet, glädje är en gåva till den andra medlöfte om hjälp. Det inbjudande hjärtats glittrande glädje – gemenskap, glädje inbjudertill gemenskap. Det upprymda hjärtats uppsluppna glädje – integration, glädje gör attmänniskan kan glömma sitt lidande och närma sig den hon önskar vara. Detstämningsfulla hjärtats högtidliga glädje – bevärdigande, glädje skapar en anda ochatmosfär där människan upplever sig hedrad. Det fridfulla hjärtats stora glädje –räddning, en glädje visar sig när människan har erhållit det som kan begäras av gott ochundsluppet ont och är förnöjd med sin levnads lott. Förhoppningen är att dennagrundforskning ska öppna för ett nytt seende som kan leda till att glädjeuppmärksammas i vårdandets värld och artikuleras där.

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In the shadow of ethno-cultural stereotypes: gender, equity and ethnic relations in Sweden Scientific debates about cultural differences between ”Swedes” and migrants/ethnic minorities in Sweden have fuelled stereotypical categorizations and a socio-cultural demarcation between ”us” and ”them”. The authors argue that this development has underpinned constructions of foreignness. In the light of a critical review of the current debate on honour related violence, the authors discuss – inspired by Georg Simmel’s and Erving Goffman’s classic texts on the stranger, the stigma and the construction of foreignness – alternative understandings of culture and politics of belonging with a focus on gender, agency and identity formation. Formation of cultural and ethnic identity should be related, the authors conclude, to a dynamic interplay between the past and the present. Moreover, the social dimension should be highlighted, in order to avoid a stigmatizing culturalism.

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Life quality in families: close relations and “the good life” The aim of this paper is to explore how aspects and qualities of modern family life influence subjective well-being. Although the patterns of family, work and sexuality have changed dramatically the last four decades, it is here claimed that the family is still an important base of socialization and upbringing. Thus the study of processes within the family can contribute to the understanding of the environment in which many children grow up. In most families, work, partner and family roles are intertwined, and one central hypothesis of this work is that family members influence each other in the individual formation of well-being. The main research question of this study asks: How is life quality affected by the quality of parent-child and the partner relationships and aspects of their shared everyday life? Empirical implications are tested against 2002-data from a representative, Norwegian sample. Analyses conclude that the quality of parent-child and the spousal relationship, and also aspects of families’ everyday life such as work-life balance and time pressure influence the subjective life quality, but mother’s and father’s life quality is affected by differing and partly incompatible conditions.

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In 1952, Dwyer and coworkers began testing a series of metal complexes for potential inhibition of cancer cell proliferation in animals.[l] The complexes tested were unsuitable for such studies due to their high toxicity. Therefore, no further work was done on the project. However, in 1965, Rosenberg and coworkers revisited the possibility of potential metal-based drugs. Serendipitously, they discovered that cis-diamminedichloroplatinum(lI) (cisplatin) inhibits cell division in E. coli.[2] Further studies of this and other platinum compounds revealed inhibition of tumor cell lines sarcoma 180 and leukemia LI2l0 in mice.[l] Cisplatin was approved by the Food and Drug Administration in 1970 as a chemical chemotherapeutic agent in the treatment of cancer. The drug has primarily been used in the treatment of testicular and ovarian cancers, although the powerful chemotherapeutic properties of the compound indicate use against a variety of other cancers.[3] The toxicity of this compound, however, warrants the development of other metal-based potential antitumor agents. The success of cisplatin, a transition-metal-based chemotherapeutic, opened the doors to a host of research on the antitumor effects of other transition-metal complexes. Beginning in the 1970s, researchers looked to rhodium for potential use in antitumor complexes. Dirhodium complexes with bridging equatorial ligands (Figure I) were the primary focus for this research. The overwhelming majority of these complexes were dirhodium(II) carboxylate complexes, containing two rhodium(II) centers, four equatorial ligands in a lantero formation around the metal center, and an axial ligand on either end. The family of complexes in Figure 1 will be referred to as dirhodium(II) carboxylate complexes. The dirhodium centers are each d? with a metal-metal bond between them. Although d? atoms are paramagnetic, the two unpaired electrons pair to make the complex diamagnetic. The basic formula of the dirhodium(lI) carboxylate complexes is Rh?(RCOO)?(L)? with R being methyl, ethyl, propyl, or butyl groups and L being water or the solvent in which the complex was crystalized. Of these dirbodium(II) carboxylate complexes, our research focuses on Rb la and two other similar complexes Rh2 and Rh3 (Figure 2). Rh2 is an activated form of Rhla, with four acetonitrile groups in place of two of the bidentate acetate ligands. Rh3 is similar to Rhla, with trifluoromethyl groups in place of the methyl groups on the acetate ligands.