670 resultados para Dalton
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Objetivo: investigar a influência de duas sessões únicas de exercício resistido (circuito com pesos) e aeróbio sobre as alterações pressóricas, em indivíduos sedentários e normotensos. Métodos: foram avaliados pela monitorização numa situação controle, sem realização de exercícios (MAPA 1) 25 indivíduos, após exercício resistido (MAPA 2) e após exercício aeróbio (MAPA 3). Os exercícios resistidos foram realizados sob forma de circuito com pesos, com intensidade de 40% da força máxima individual e os exercícios aeróbicos em cicloergômetro, com intensidade entre 60% e 70% da freqüência cardíaca (FC) máxima alcançada no teste ergométrico. Resultados: a pressão arterial sistólica (PAS) de 24h e sub-períodos vigília e sono não apresentaram variações estatisticamente significantes quando comparada à MAPA2 e MAPA3 e MAPA2 e MAPA3 entre si. A pressão arterial diastólica (PAD) de 24h e diurna apresentaram reduções significantes (P<0,05). A média da freqüência cardíaca de 24h e no período vigília apresentou aumentos significativos (P<0,05) quando comparada a MAPA2 à MAPA3. Conclusão: uma sessão única de exercício resistido em indivíduos normotensos foi suficiente para promover reduções significativas dos níveis tensionais, no período de sono após o exercício, e a de exercício aeróbio nesses mesmos indivíduos, foi mais eficaz em promover reduções significativas dos níveis pressóricos.
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Reactions of copper(II) with 3-phenylhydrazopentane-2,4-diones X-2-C6H4-NHN = C{C(= O)CH3}(2) bearing a substituent in the ortho-position [X = OH (H2L1) 1, AsO3H2 (H3L2) 2, Cl (HL3) 3, SO3H (H2L4) 4, COOCH3 (HL5) 5, COOH (H2L6) 6, NO2 (HL7) 7 or H (HL8) 8] lead to a variety of complexes including the monomeric [CuL4(H2O)(2)]center dot H2O 10, [CuL4(H2O)(2)] 11 and [Cu(HL4)(2)(H2O)(4)] 12, the dimeric [Cu-2(H2O)(2)(mu-HL2)(2)] 9 and the polymeric [Cu(mu-L-6)](n)] 13 ones, often bearing two fused six-membered metallacycles. Complexes 10-12 can interconvert, depending on pH and temperature, whereas the Cu(II) reactions with 4 in the presence of cyanoguanidine or imidazole (im) afford the monomeric compound [Cu(H2O)(4){NCNC(NH2)(2)}(2)](HL4)(2)center dot 6H(2)O 14 and the heteroligand polymer [Cu(mu-L-4)(im)](n) 15, respectively. The compounds were characterized by single crystal X-ray diffraction (complexes), electrochemical and thermogravimetric studies, as well as elemental analysis, IR, H-1 and C-13 NMR spectroscopies (diones) and ESI-MS. The effects of the substituents in 1-8 on the HOMO-LUMO gap and the relative stability of the model compounds [Cu(OH)(L-8)(H2O)]center dot H2O, [Cu(L-1)(H2O)(2)]center dot H2O and [Cu(L-4)(H2O)(2)]center dot H2O are discussed on the basis of DFT calculations that show the stabilization follows the order: two fused 6-membered > two fused 6-membered/5-membered > one 6-membered metallacycles. Complexes 9, 10, 12 and 13 act as catalyst precursors for the peroxidative oxidation (with H2O2) of cyclohexane to cyclohexanol and cyclohexanone, in MeCN/H2O (total yields of ca. 20% with TONs up to 566), under mild conditions.
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Two multinuclear complexes [Fe-6(mu(3)-O)(2)(mu(4)-O-2)L-10(OAc)(2)(H2O)(2)]center dot 2.625Et(2)O center dot 2.375H(2)O (1) and [(Fe11Cl)-Cl-III-(mu(4)-O)(3)(mu(3)-O)(5)L-16(dmf)(2.5)(H2O)(0.5)]center dot Et2O center dot 1.25dmf center dot 3.8H(2)O (2), where HL = 3,4,5-trimethoxybenzoic acid and dmf = dimethylformamide, have been prepared from trinuclear iron(III) carboxylates via their structural rearrangement in dimethylformamide or diethyl ether-dimethylformamide 9:1, respectively, and slow vapor diffusion of diethyl ether into the reaction mixture. Both compounds have been characterized by X-ray diffraction, optical, Mossbauer spectroscopy, and magnetic measurements. Complex 1 possesses a hexanuclear ferric peroxido-dioxido {Fe-6(O-2)(O)(2)}(12+) core unit, which adopts a recliner conformation, while complex 2 contains an unprecedented {Fe11O8Cl}(16+) core, in which 9 ferric ions are six-coordinate and the remaining two are five-coordinate. Another structural feature of note of the undecanuclear core is the presence of a deformed cubane entity {Fe-4(mu(3)-O)(mu(4)-O)(3)}(4+). Both complexes act as catalyst precursors for the oxidation of cyclohexane to cyclohexanol and cyclohexanone with aqueous H2O2, in the presence of pyrazinecarboxylic acid. Remarkable TONs and TOFs (the latter mainly for 1) with concomitant quite good yields have been achieved under mild conditions. Moreover, 1 exhibits remarkably high activity in an exceptionally short reaction time (45 min), being unprecedented for any metal catalyzed alkane oxidation by H2O2. The catalytic reactions proceed via Fenton type chemistry.
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OBJETIVO: Analisar instrumento de medição da adesão ao tratamento da hipertensão por meio da "Teoria da Resposta ao Item".MÉTODOS: Estudo analítico com 406 hipertensos com complicações associadas, atendidos na atenção básica em Fortaleza, CE, 2011, pela "Teoria da Resposta ao Item". As etapas de execução foram: teste de dimensionalidade, calibração dos itens; tratamento dos dados e construção da escala, analisadas com base no modelo de resposta gradual. Estudo da dimensionalidade do instrumento foi feito pela análise da matriz de correlação policórica e análise fatorial de informação completa. Utilizou-se o software Multilog para calibração dos itens e estimação dos escores.RESULTADOS: Os itens referentes ao tratamento medicamentoso foram os mais diretamente relacionados à adesão, enquanto aqueles referentes ao tratamento não medicamentoso precisam ser reformulados, pois possuíram menor quantidade de informação psicométrica e baixa discriminação. A independência dos itens, o reduzido número de níveis da escala e as baixas variâncias explicadas no ajuste dos modelos mostraram as principais fragilidades do instrumento analisado. A "Teoria da Resposta ao Item" mostrou-se relevante para análise, pois avaliou o respondente quanto à adesão ao tratamento da hipertensão, ao nível de dificuldade dos itens e à sua capacidade de discriminação entre indivíduos com diferentes níveis de adesão, o que gerou maior quantidade de informação.CONCLUSÕES: O instrumento analisado é limitado para medir a adesão ao tratamento da hipertensão, mediante análise pela "Teoria da Resposta ao Item", e necessita de ajustes. A adequada formulação dos itens é importante para medir precisamente o traço latente desejado.
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Dalton Trans., 2003, 3328-3338
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OBJETIVO Elaborar e validar instrumento de avaliação da adesão ao tratamento da hipertensão arterial sistêmica, com base na teoria da resposta ao item. MÉTODOS O desenvolvimento do instrumento envolveu procedimentos teóricos, empíricos e analíticos. Os procedimentos teóricos compreenderam a definição do constructo adesão ao tratamento da hipertensão arterial sistêmica, identificação dos domínios intervenientes e a elaboração do instrumento, seguida da análise semântica e conceitual por peritos. O procedimento empírico englobou a aplicação do instrumento a 1.000 usuários com hipertensão arterial sistêmica, atendidos em um centro de referência em Fortaleza, CE, em 2012. A etapa analítica validou o instrumento por meio da análise psicométrica e dos procedimentos estatísticos. O modelo da teoria da resposta ao item usado na análise foi o da resposta gradual de Samejima. RESULTADOS Doze dos 23 itens do instrumento inicial foram calibrados e permaneceram na versão final. O coeficiente alfa (α) de Cronbach foi de 0,81. Os itens referentes ao uso da medicação quando apresenta algum sintoma e o uso de gordura apresentaram bom desempenho, pois tiveram melhor poder de discriminar os indivíduos que aderem ao tratamento. Deixar de tomar a medicação alguma vez e o consumo de carnes brancas apresentaram menor poder de discriminação. Itens referentes à realização de exercício físico e ser rotina seguir o tratamento não medicamentoso tiveram maior dificuldade de resposta. O instrumento mostrou-se mais apropriado para medir a baixa adesão ao tratamento da hipertensão arterial sistêmica do que a alta adesão. CONCLUSÕES O instrumento mostrou-se adequado para avaliar a adesão ao tratamento da hipertensão arterial sistêmica, pois consegue diferenciar os indivíduos com alta adesão daqueles com baixa adesão. Sua utilização pode facilitar a identificação e aferição do cumprimento à terapêutica prescrita, além de viabilizar o estabelecimento de metas a serem alcançadas.
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Two new metal- organic compounds {[Cu-3(mu(3)-4-(p)tz)(4)(mu(2)-N-3)(2)(DMF)(2)](DMF)(2)}(n) (1) and {[Cu(4ptz) (2)(H2O)(2)]}(n) (2) {4-ptz = 5-(4-pyridyl)tetrazolate} with 3D and 2D coordination networks, respectively, have been synthesized while studying the effect of reaction conditions on the coordination modes of 4-pytz by employing the [2 + 3] cycloaddition as a tool for generating in situ the 5-substituted tetrazole ligands from 4-pyridinecarbonitrile and NaN3 in the presence of a copper(II) salt. The obtained compounds have been structurally characterized and the topological analysis of 1 discloses a topologically unique trinodal 3,5,6-connected 3D network which, upon further simplification, results in a uninodal 8-connected underlying net with the bcu (body centred cubic) topology driven by the [Cu-3(mu(2)-N-3)(2)] cluster nodes and mu(3)-4-ptz linkers. In contrast, the 2D metal-organic network in 2 has been classified as a uninodal 4-connected underlying net with the sql [Shubnikov tetragonal plane net] topology assembled from the Cu nodes and mu(2)-4-ptz linkers. The catalytic investigations disclosed that 1 and 2 act as active catalyst precursors towards the microwave-assisted homogeneous oxidation of secondary alcohols (1-phenylethanol, cyclohexanol, 2-hexanol, 3-hexanol, 2-octanol and 3-octanol) with tert-butylhydroperoxide, leading to the yields of the corresponding ketones up to 86% (TOF = 430 h(-1)) and 58% (TOF = 290 h(-1)) in the oxidation of 1-phenylethanol and cyclohexanol, respectively, after 1 h under low power ( 10 W) microwave irradiation, and in the absence of any added solvent or additive.
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A series of six new mixed-ligand dinuclear Mn(II, II) complexes of three different hydrazone Schiff bases (H3L1, H3L2 and H3L3), derived from condensation of the aromatic acid hydrazides benzohydrazide, 2-aminobenzohydrazide or 2-hydroxybenzohydrazide, with 2,3-dihydroxy benzaldehyde, respectively, is reported. Reactions of Mn(NO3)(2) center dot 4H(2)O with the H3L1-3 compounds, in the presence of pyridine (1 : 1 : 1 mole ratio), in methanol at room temperature, yield [Mn(H2L1)(py)(H2O)](2)(NO3)(2) center dot 2H(2)O (1 center dot 2H(2)O), [Mn(H2L2)(py)(CH3OH)](2)(NO3)(2) center dot 4H(2)O (2 center dot 4H(2)O) and [Mn(H2L3)(py)(H2O)](2)(NO3)(2) (3) respectively, whereas the use of excess pyridine yields complexes with two axially coordinated pyridine molecules at each Mn(II) centre, viz. [Mn(H2L1)(py)(2)] 2(NO3)(2) center dot H2O (4 center dot H2O), [Mn(H2L2)(py) H-O (6 center dot 2CH(3)OH), respectively. In all the complexes, the (H2L1-3)-ligand coordinates in the keto form. Complexes 1 center dot 2H(2)O, 2 center dot 4H(2)O, 4 center dot H2O, 5 center dot 2H(2)O and 6 center dot 2CH(3)OH are characterized by single crystal X-ray diffraction analysis. The complexes 1, 2 and 6, having different coordination environments, have been selected for variable temperature magnetic susceptibility measurements to examine the nature of magnetic interaction between magnetically coupled Mn(II) centres and also for exploration of the catalytic activity towards microwave assisted oxidation of alcohols. A yield of 81% (acetophenone) is obtained using a maximum of 0.4% molar ratio of catalyst relative to the substrate in the presence of TEMPO and in aqueous basic solution, under mild conditions.
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fac-[MBr(CO)(3)(pypzH)] (M = Mn, Re; pypzH = (3-(2-pyridyl) pyrazole) complexes are prepared from fac[ MBr(CO)(3)(NCMe)(2)] and pypzH. The result of their deprotonation depends on the metallic substrate: the rhenium complex affords cleanly the bimetallic compound [fac-{Re(CO)(3)(mu(2)-pypz)}] 2 (mu(2)-pypz = mu(2)-3-(2pyridyl-. 1N) pyrazolate-2. 1N), which was crystallographically characterized, whereas a similar manganese complex was not detected. When two equivalents of pyridylpyrazolate are used, polymetallic species [fac-M(CO) 3(mu(2)-pypz)(mu(3)-pypz) M'] (mu(3)-pypz = mu(3)-3-(2-pyridyl-kappa N-1) pyrazolate-1 kappa 2N, N: 2. 1N:; M = Mn, M' = Li, Na, K; M = Re, M' = Na) are obtained. The crystal structures of the manganese carbonylate complexes were determined. The lithium complex is a monomer containing one manganese and one lithium atom, whereas the sodium and potassium complexes are dimers and reveal an unprecedented coordination mode for the bridging 3-(2-pyridyl) pyrazolate ligand, where the nitrogen of the pyridyl fragment and the nitrogen-1 of pyrazolate are chelated to manganese atoms, and each nitrogen-2 of pyrazolate is coordinated to two alkaline atoms. The polymetallic carbonylate complexes are unstable in solution and evolve spontaneously to [fac-{Re(CO) 3(mu(2)-pypz)}](2) or to the trimetallic paramagnetic species [MnII(mu(2)-pypz) 2{fac-{MnI(CO) 3(mu(2)-pypz)}(2)}]. The related complex cis-[MnCl2(pypzH)(2)] was also synthesized and structurally characterized. The electrochemical behavior of the new homo-and heteropolymetallic 3-(2-pyridyl) pyrazolate complexes has been studied and details of their redox properties are reported.
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The Ni-II and Zn-II complexes [MCl(Tpms(Ph))] (Tpms(Ph) = SO3C(pz(Ph))(3), pz = pyrazolyl; M = Ni 2 or Zn 3) and the Cu-II complex [CuCl(Tpms(Ph))(H2O)] (4) have been prepared by treatment of the lithium salt of the sterically demanding and coordination flexible tris(3-phenyl-1-pyrazolyl)methanesulfonate (Tpms(Ph))(-) (1) with the respective metal chlorides. The (Tpms(Ph))(-) ligand shows the N-3 or N2O coordination modes in 2 and 3 or in 4, respectively. Upon reaction of 2 and 3 with Ag(CF3SO3) in acetonitrile the complexes [M(Tpms(Ph))-(MeCN)](CF3SO3) (M = Ni 5 or Zn 6, respectively) were formed. The compounds were obtained in good yields and characterized by analytic and spectral (IR, H-1 and C-13{H-1} NMR, ESI-MS) data, density functional theory (DFT) methods and {for 4 and [(Bu4N)-Bu-n](Tpms(Ph)) (7), the tatter obtained upon Li+ replacement by [(Bu4N)-Bu-n](+) in Li(Tpms(Ph))} by single crystal X-ray diffraction analysis. The Zn-II and Cu-II complexes (3 and 4, respectively) act as efficient catalyst precursors for the diastereoselective nitroaldol reaction of benzaldehydes and nitroethane to the corresponding beta-nitroalkanols (up to 99% yield, at room temperature) with diastereoselectivity towards the formation of the anti isomer, whereas the Ni-II complex 2 only shows a modest catalytic activity.
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The reactions between 4'-phenyl-terpyridine (L) and nitrate, acetate or chloride Cu(II) salts led to the formation of [Cu(NO3)(2)L] (1), [Cu(OCOCH3)(2)L]center dot CH2Cl2 (2 center dot CH2Cl2)and [CuCl2L]center dot[Cu(Cl)(mu-Cl)L](2) (3), respectively. Upon dissolving 1 in mixtures of DMSO-MeOH or EtOH-DMF the compounds [Cu(H2O){OS(CH3)(2)}L]-(NO3)(2) (4) and [Cu(HO)(CH3CH2OH)L](NO3) (5) were obtained, in this order. Reaction of 3 with AgSO3CF3 led to [CuCl(OSO2CF3)L] (6). The compounds were characterized by ESI-MS, IR, elemental analysis, electrochemical techniques and, for 2-6, also by single crystal X-ray diffraction. They undergo, by cyclic voltammetry, two single-electron irreversible reductions assigned to Cu(II) -> Cu(I)and Cu(I) -> Cu(0) and, for those of the same structural type, the reduction potential appears to correlate with the summation of the values of the Lever electrochemical EL ligand parameter, which is reported for the first time for copper complexes. Complexes 1-6 in combination with TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxyl radical) can exhibit a high catalytic activity, under mild conditions and in alkaline aqueous solution, for the aerobic oxidation of benzylic alcohols. Molar yields up to 94% (based on the alcohol) with TON values up to 320 were achieved after 22 h.
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Treatment of a dichloromethane solution of trans-[Mo(NCN){NCNC(O)R}(dppe)(2)]Cl [R = Me (1a), Et (1b)] (dppe = Ph2PCH2CH2PPh2) with HBF4, [Et3O][BF4] or EtC(O)Cl gives trans-[Mo(NCN)Cl-(dppe)(2)]X [X = BF4 (2a) or Cl (2b)] and the corresponding acylcyanamides NCN(R')C(O)Et (R' = H, Et or C(O)Et). X-ray diffraction analysis of 2a (X = BF4) reveals a multiple-bond coordination of the cyanoimide ligand. Compounds 1 convert to the bis(cyanoimide) trans-[Mo(NCN)(2)(dppe)(2)] complex upon reaction with an excess of NaOMe (with formation of the respective ester). In an aprotic medium and at a Pt electrode, compounds 1 (R = Me, Et or Ph) undergo a cathodically induced isomerization. Full quantitative kinetic analysis of the voltammetric behaviour is presented and allows the determination of the first-order rate constants and the equilibrium constant of the trans to cis isomerization reaction. The mechanisms of electrophilic addition (protonation) to complexes 1 and the precursor trans[Mo(NCN)(2)(dppe)(2)], as well as the electronic structures, nature of the coordination bonds and electrochemical behaviour of these species are investigated in detail by theoretical methods which indicate that the most probable sites of the proton attack are the oxygen atom of the acyl group and the terminal nitrogen atom, respectively.
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A number of novel, water-stable redox-active cobalt complexes of the C-functionalized tripodal ligands tris(pyrazolyl)methane XC(pz)(3) (X = HOCH2, CH2OCH2Py or CH2OSO2Me) are reported along with their effects on DNA. The compounds were isolated as air-stable solids and fully characterized by IR and FIR spectroscopies, ESI-MS(+/-), cyclic voltammetry, controlled potential electrolysis, elemental analysis and, in a number of cases, also by single-crystal X-ray diffraction. They showed moderate cytotoxicity in vitro towards HCT116 colorectal carcinoma and HepG2 hepatocellular carcinoma human cancer cell lines. This viability loss is correlated with an increase of tumour cell lines apoptosis. Reactivity studies with biomolecules, such as reducing agents, H2O2, plasmid DNA and UV-visible titrations were also performed to provide tentative insights into the mode of action of the complexes. Incubation of Co(II) complexes with pDNA induced double strand breaks, without requiring the presence of any activator. This pDNA cleavage appears to be mediated by O-centred radical species.
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Molybdenum and tungsten complexes containing the pypzH (3-(2-pyridyl)pyrazole) ligand as a chelating bidentate are prepared: [Mo(CO)(4)(pypzH)], cis-[MoBr(eta(3)-allyl)(CO)(2)(pypzH)], cis-[MoCl(eta(3)-methallyl)(CO)(2)(pypzH)], [MI2(CO)(3)(pypzH)] (M = Mo, W) from [Mo(CO)(4)(NBD)] or the adequate bis(acetonitrile) complexes. The deprotonation of the molybdenum allyl or methallyl complexes affords the bimetallic complexes [cis-{Mo(eta(3)-allyl)(CO)(2)(mu(2)-pypz)}](2) or [cis-{Mo(eta(3)-methallyl)(CO)(2)(mu(2)-pypz)}](2) (mu(2)-pypz = mu(2)-3-(2-pyridyl-kappa N-1) pyrazolate-2 kappa N-1). The allyl complex was subjected to an electrochemical study, which shows a marked connection between both metallic centres through the bridging pyridylpyrazolates.
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From January 1988 to January 1989 all the heart transplant and bone marrow recipients at the Instituto do Coração of the Hospital das Clínicas of the University of São Paulo Medical School were studied for the incidence and morbidity associated with herpesviruses infections after transplantation. Five bone marrow and 5 heart transplant recipients were followed for a mean of 4.2 months post-transplantation. All the patients were seropositive for cytomegalovirus (CMV) before admission and 80% experienced one or more recurrences during the observation period. Of the 12 episodes of CMV infection, that were identified in this study, 83% were accompanied by clinical or laboratory abnormalities. However, there was only one case of severe disease. The overall incidence of infection for herpes simplex (HSV) was 50%. Although most of HSV reactivations were oral or genital, one case of HSV hepatitis occurred. One of the 6 episodes of HSV infections that were treated with acyclovir showed an unsatisfactory response and was successfully managed with ganciclovir. All the individuals had anti-varicella zoster virus antibodies, but none of them developed infection. The study emphasizes the importance of active diagnostic surveillance of herpesvirus infections in transplant patients. Both CMV and HSV reactivations showed high incidence and important morbidity and thus, deserve prophylactic therapy.