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In the present work, new rhenium(i) polypyridyl compounds, fac-[Re(L)(CO)3(cbz2phen)](+/0) where cbz2phen = 4,7-di(9H-carbazol-9-yl)-1,10-phenanthroline and L = Cl(-), pyridine (py) or 2-aminomethylpyridine (ampy) were synthesized and characterized by (1)H NMR, UV-Vis and IR spectroscopy combined with theoretical calculations using time-dependent density functional theory (TD-DFT). Their photophysical properties were investigated by steady state and time-resolved emission spectroscopy. These compounds show a strong and broad absorption band around 350-500 nm that, also by TD-DFT, corresponds to the carbazol → phenanthroline intraligand charge transfer transition, (1)ILCTcbz2phen, with some contribution of the Re(i) → phenanthroline metal-to-ligand charge transfer transition, (1)MLCTRe→cbz2phen. In contrast to typical Re(i) polypyridyl complexes, cbz2phen-based Re(i) compounds exhibit two emission maxima in CH3CN solution and relatively low emission quantum yields, 10(-3)-10(-2). Solution phase time-resolved photoluminescence and excited state quenching experiments provided meaningful information on the presence of multiple emitter states after light excitation, which were identified as an (1)ILCTcbz2phen excited state deactivation at higher energies and a long-lived phosphorescence attributed to the (3)MLCTRe→cbz2phen excited state. When embedded into a PMMA matrix, the radiative decay from the singlet state is inhibited and the contribution of both (3)MLCT and (3)ILCTcbz2phen to the luminescence is observed. The photophysics of these Re(i) compounds reported herein provide new insights into the understanding of substitutional groups on the polypyridyl ligands that are relevant to practical and fundamental development of photo-induced molecular devices.

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10-(Octyloxy) decyl-2-(trimethylammonium) ethyl phosphate (ODPC) is an alkylphospholipid that can interact with cell membranes because of its amphiphilic character. We describe here the interaction of ODPC with liposomes and its toxicity to leukemic cells with an ED-50 of 5.4, 5.6 and 2.9 microM for 72 h of treatment for inhibition of proliferation of NB4, U937 and K562 cell lines, respectively, and lack of toxicity to normal hematopoietic progenitor cells at concentrations up to 25 microM. The ED-50 for the non-malignant HEK-293 and primary human umbilical vein endothelial cells (HUVEC) was 63.4 and 60.7 microM, respectively. The critical micellar concentration (CMC) of ODPC was 200 microM. Dynamic light scattering indicated that dipalmitoylphosphatidylcholine (DPPC) liposome size was affected only above the CMC of ODPC. Differential calorimetric scanning (DCS) of liposomes indicated a critical transition temperature (T(c)) of 41.5 degrees C and an enthalpy (H) variation of 7.3 kcal mol(-1). The presence of 25 microM ODPC decreased T(c) and H to 39.3 degrees C and 4.7 kcal mol(-1), respectively. ODPC at 250 microM destabilized the liposomes (36.3 degrees C, 0.46 kcal mol(-1)). Kinetics of 5(6)-carboxyfluorescein (CF) leakage from different liposome systems indicated that the rate and extent of CF release depended on liposome composition and ODPC concentration and that above the CMC it was instantaneous. Overall, the data indicate that ODPC acts on in vitro membrane systems and leukemia cell lines at concentrations below its CMC, suggesting that it does not act as a detergent and that this effect is dependent on membrane composition.

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The purpose of this study was to evaluate the prevalence of symptomatic parasitic infections in adult renal transplant recipients. We retrospectively analyzed a sample of 657 adult renal transplant recipients performed from January 2001 to December 2005 for immunosuppression protocol, clinical manifestations, parasite diagnosis, treatments, and outcomes. The prevalence of symptomatic parasitosis infections was 2.4% (16/657). None of the infected patients received cyclosporine in their immunosuppression protocol. Most of the infections were caused by Strongyloids stercoralis (n = 11), followed by Giardia lamblia (n = 3), Toxoplasma gondii (n = 1), and Trypanosoma cruzi: (n = 1). Strongyloides stercoralis was the most frequent agent, causing three cases of hyperinfection including one fatal case. With the new immunosuppressive regimes there must be a suspicion of parasitic infection to avoid the diagnostic delay that can be fatal. Strategies, including empiric treatment for S. stercoralis, must be considered.

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We describe ten children, aging 5 years and 1 month until 5 years and 11 months, when the phonoaudiological assessment was conducted. They are divided according to cerebrovascular disease, in CVD group (CVD-G) and control group (cG). Children were seen and CVD was confirmed in the acute phase at UNICAMP hospital. Audiologic assessment, protocol for Infant language assessment, and Peabody picture vocabulary test were used in the evaluations. The qualitative analysis of the subjects from a phonoaudiological and neurological point of view has shown the recovery of acquired language disorder (ALD) with no influence whatsoever in the development of 2 subjects and subtle language and/or learning process alterations for 3 subjects. The cases study has revealed that all aspects of language development in preschool children should be analyzed in an individual, quantitative, and qualitative basis to lead to conclusive findings.

São descritos 10 casos de crianças com idade cronológica entre 5 anos e 1 mês e 5 anos e 11 meses, divididas em grupo de doença cerebrovascular, (G-DCV) e grupo controle (Gc). As crianças do G-DCV apresentaram DCV confirmada na fase aguda através de exame neurológico clínico e de imagem na UNICAMP. Nas avaliações utilizou-se triagem audiológica, protocolo de avaliação da linguagem infantil, teste de vocabulário por imagens Peabody, com o objetivo de avaliar os diversos subsistemas lingüísticos e as noções perceptivo-cognitivas. Na análise qualitativa do G-DCV, do ponto de vista fonoaudiológico e neurológico, quando comparado ao Gc, mostrou recuperação completa do distúrbio adquirido de linguagem (DAL) em 2 crianças e alterações de linguagem em 3. O estudo dos casos revelou que os diversos aspectos que constituem a linguagem em desenvolvimento na criança pré-escolar devem ser analisados de forma individual, quantitativa e qualitativamente para achados conclusivos.

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