Solution and Solid-State Characterization of Zn(II) Complexes Containing A New Tridentate N\u3csub\u3e2\u3c/sub\u3es Ligand

A new N2S ligand bis(pyridyl)(2-mercapto-1-methylimidazolyl)methane (2, Py2MeImS) has been synthesized and characterized. Treatment of this ligand with bromide and triflate salts of Zn(II) results in the complexes (Py2MeImS)ZnBr2 (3) and [(Py2MeImS)2Zn](OTf)2 (4), respectively. The solid-state structure of (Py2MeImS)ZnBr2 shows bidentate N,N-coordination of Py2MeImS to the zinc ion, with the sulfur atom of the 2-mercaptoimidazole moiety uncoordinated. Two conformers of 3 rapidly interconvert in solution at room temperature, and variable temperature NMR studies and DFT calculations were used to help assign the likely identity of these conformers. In contrast, the crystal structure of [(Py2MeImS)2Zn] (OTf)2 exhibits a zinc ion with a distorted octahedral geometry where the two sulfur atoms of the two ligands are coordinated to the zinc center in a cis-configuration. Even though the cis-isomer (4-cis) is calculated to be lower in energy than the trans-isomer (4-trans), the low temperature 1H NMR spectrum of 4 reveals a single symmetric species that is inconsistent with the cis-isomer observed in the solid-state structure. DFT calculations propose alternative higher energy structures, including a trans-configuration of the coordinated S-atoms of the two Py2MeImS ligands, as well as structures in which the 2-mercaptoimidazole groups are no longer coordinated to the zinc(II) center. These studies provide valuable insight into the potential binding modes of this new ligand and its behavior in solution

Development of Zn(II) Hydroxide Complexes Containing N2S Donor Atom Sets: Molecular Motifs of the Active Site of Peptide Deformylase

The function of the metalloenzyme peptide deformylase (PDF) is to deformylate proteins that contain N-formylated methionine. Since this is unique to prokaryotes, elucidation of the detailed mechanism of how PDF works may be important for antibiotic design. In Eubacteria, protein synthesis is initiated by a special transfer-RNA charged with N-formylmethionine which blocks the reactive amino group preventing unfavorable side reactions. This is specific only to prokaryotes and removal of the formyl group as the polypeptide exits the ribosomal tunnel is essential for protein synthesis to continue. Failure to deformylate the amino terminal will cause the formyl group to be buried causing incorrect folding of the proteins. Motivation for studying the mechanism comes from the unusual finding that the most active form of PDF is not a zinc-containing enzyme but instead an iron-containing enzyme. In order to explain the unusual metal dependency, we have prepared two new N2S ligands (ligand A and B), which have been shown by X-ray crystallography to form mononuclear Zn(II)-Br complexes. These N2S ligands model the cysteine and two histidine binding motif present in the active site of PDF but have unique features that are expected to result in mononuclear iron complexes. Details of the synthetic procedures and characterization data of our Zn(II) complexes is presented

Transitory dance: Towards a revision of qualitative parameters in contemporary dance.

Este trabalho traça um panorama do contexto do Programa de Fomento à Dança para a cidade de São Paulo, a partir do estudo de sua 22a edição, realizada entre os anos de 2016 e 2017. Entendemos a Lei 14.071/2005 como um sistema hipercomplexo, que se desenvolve em coimplicação com os ambientes artístico e das políticas públicas (gestão municipal de cultura de São Paulo), e estabelecemos uma reflexão crítica em torno do conceito dança contemporânea como elemento compositivo do sistema Fomento, argumentando que a qualidade que lhe é atribuída define provisoriamente a organização do sistema como um todo que, por sua vez, estabelece conexões, também provisórias, com lógicas e ideais macropolíticas que se desdobram em questões sobre a funcionalidade da própria Lei que rege o Programa. Nesse sentido, consideramos a 22a edição desse Programa simbólica para uma discussão sobre produção em dança na cidade de São Paulo, sob a hipótese de que, para que haja desenvolvimento de autonomia no sistema Fomento à Dança para a cidade de São Paulo, é importante a fricção dos ambientes artístico e das políticas públicas, garantindo o desenvolvimento de sua complexidade.This work provides an overwiew of the context of the Fomento à Dança Program for the city of São Paulo, based on the study of its 22nd edition, which took place between 2016 and 2017. Considering this Law as a hypercomplex system, developing in co-implication with the environments of art and public policies (municipal management of culture in São Paulo), we establish a critical reflection around the concept of contemporary dance as a compositional element of the Fomento system, arguing that the quality attributed to it provisionally defines the systems organization as a whole, which, in turn, establishes equally provisional connections with logics and macro-political ideals, which unfold into questions about the functionality of Law 14.071/2005, which governs the Program. In this sense, we consider this edition symbolic for a discussion of dance production in the city of São Paulo, operating under the hypothesis that, for the development of autonomy in the Fomento à Dança Program for the city of São Paulo, friction between the artistic and public political enviroments is important, ensuring the development of its complexity

Structural and functional studies of a Beauveria bassiana lipase immobilized and expressed in Aspergillus nidulans: sensitivity of glioblastoma cell lines to hydrolysates of brazilian oils

Esse trabalho teve como objetivo a obtenção e caracterização de uma cepa transformante de Aspergilus nidulans para produção de uma lipase de Beauveria bassiana (denominada Bbl1) por meio do vetor pExpyr, utilizando xarope de milho como fonte de carbono indutora. Para isso utilizou-se o gene sob referência XP_008602131.1 (denominado bbl1) do NCBI que foi introduzido em vetores de pGEM-T, para multiplicação, e no pExpyr, para expressão. Foi feita a modelagem molecular dessa enzima, revelando cavidades hidrofóbicas para interação com substrato, e a \"tampa\", considerada característica comum das lipases \"verdadeiras\". A produção de Bbl1 em cultivos contendo maltose foi aproximadamente o dobro em relação à cepa selvagem B. bassiana. Posteriormente, com o intuito de melhorar a produção e baratear os custos de fermentação desta cepa, a maltose e o tampão HEPES (insumos caros e utilizados em escala laboratorial, porém inviáveis em padrão industrial) foram substituídos respectivamente por xarope de milho e tampão fosfato de sódio; o resultado foi a obtenção de quase 40 U.mL-1 de atividade de lipases em Erlenmeyer de 125 mL, quadruplicando a produção em relação a cepa selvagem. A Bbl1 foi purificada em colunas de Octyl-Sepharose e DEAE-celulose. Essa enzima demonstrou-se estável em solução com 0,5% de tween-20 e tween-80, e hiper-ativada na presença destes dois detergentes e de Triton X-100. Além disso, os ácidos oleico e linoleico demonstraram-se como inibidores análogos a não-competitivos. O estudo de imobilização revelou que o suporte de Octyl-Sepharose é o mais ideal para ativação de Bbl1, sendo que a atividade relativa da mesma foi cerca de 123%, em relação a mesma enzima em solução aquosa. Quanto à estabilidade térmica e ao pH, a imobilização promoveu um ganho de estabilidade nas temperaturas de 30°C até 60°C nos derivados de Octyl, Phenyl, Butyl, DEAE-celulose, MANAE e PEI, e na faixa de pH de 3 até 9 nesses mesmos suportes estudados, em comparação à enzima em solução. Por meio de estudos cinéticos, observou-se que a velocidade máxima de Bbl1 imobilizada em Octyl foi 2,39 vezes maior e o respectivo valor de K0,5, 2,7 vezes menor em relação à Bbl1 livre. O padrão de inibição pelos ácidos oleico e linoleico sofreu alteração em Bbl1 imobilizada, sendo dependente da concentração destes inibidores. Os produtos hidrólise dos óleos de açaí e buriti foram fracionados em fases polares e apolares e aplicados em culturas de monocamada de linhagens celulares de glioblastoma LN-18. Observou-se os produtos de hidrólise do óleo de buriti provocaram redução na viabilidade respiratório das células de glioblastoma até 120 horas de exposição, enquanto que nos cultivos de células de fibroblasto observou-se um \"ganho\" de viabilidade neste mesmo período de cultivo. Por fim, esse trabalho permitiu a gratificação em obter uma cepa de A. nidulans transformante para expressão de lipase - uma enzima comercialmente onerosa e com poucos trabalhos envolvendo sua produção de forma heteróloga. Além disso, tornou-se a utilização destas enzimas na hidrólise de óleos brasileiros como um potencial agente à obtenção de insumos para o tratamento de glioblastoma.The objective of this work was to obtain and characterize a transforming strain of Aspergilus nidulans to produce a Beauveria bassiana lipase (called Bbl1) using the pExpyr vector, having corn syrup as inducing carbon source. For this purpose, the NCBI reference gene XP_008602131.1 (designated bbl1) was used, which was introduced into pGEM-T vectors for storage, and pExpyr for expression. The molecular modeling of this enzyme was performed, revealing hydrophobic cavities for the interaction with substrate, and the \"lid\", considered a common characteristic of \"true\" lipases. Production of Bbl1 in cultures containing maltose was approximately double that of B. bassiana wild strain. Later, in order to improve the production and to reduce the costs of fermentation of this strain, maltose and HEPES buffer (expensive and laboratory-grade inputs, however, not viable in an industrial standard) were replaced by corn syrup and sodium phosphate buffer; the result was the obtaining of almost 40 U.mL-1 of lipase activity in Erlenmeyer of 125 mL, quadrupling the production in relation to the wild strain. Bbl1 was purified on Octyl-Sepharose and DEAE-cellulose columns. This enzyme showed to be stable in solution with 0.5% tween-20 and tween-80, and hyperactivated in the presence of these two detergents and Triton X-100. In addition, oleic and linoleic acids have shown to be non-competitive analogues. The immobilization study revealed that Octyl-Sepharose support is the most ideal for the activation of Bbl1, and the relative enzymatic activity was about 123% in relation to the same non-immobilized enzyme. As for thermal stability and pH, immobilization promoted a stability gain at temperatures of 30 ° C to 60 ° C in the Octyl, Phenyl, Butyl, DEAEcellulose, MANAE and PEI derivatives, and in the pH range of 3 up to 9 in these same supports, compared to the enzyme in solution. By means of kinetic studies, it was observed that the maximum rate of Bbl1 immobilized on Octyl was 2.39 higher and the respective value of K0.5, 2.7 lower than the free Bbl1. The inhibition pattern for oleic and linoleic acids was altered in immobilized Bbl1, being dependent on the concentration of these inhibitors. The hydrolysis products of açai and buriti oils were fractionated in polar and nonpolar phases and applied to monolayer cultures of LN-18 glioblastoma cell lines. It was observed that the buriti oil hydrolysis products were able to cause a reduction in the respiratory viability of glioblastoma cells up to 120 hours of exposure, whereas in the fibroblast cell cultures a viability \"gain\" was observed in the same culture period. Finally, this work allowed the gratification in obtaining a strain of transforming A. nidulans for lipase expression - a commercially expensive enzyme with few studies involving its production in a heterologous way. In addition, the use of these enzymes in the hydrolysis of Brazilian oils has become a potential agent to obtain inputs for the treatment of glioblastoma

O Easy Java Simulations como ferramenta de ensino e aprendizagem

The aim of this dissertation is to introduce a simulation tool called Easy Java Simulations (EJS), created by Francisco Esquembre, and also to provide guidelines to Physics teacher at the High School level in how it could be used by promoting differentiated learning activities for his students. An analysis of the strength of the tool EJS is performed and it is introduced the whole basic and necessary procedure for constructing a simulation, from the mathematical modeling of the evolution of the physical system until the elaboration of the interface that allows the visualization of the graphic elements. As a final product of the dissertation, it is presented an introductory guide to EJS for all teachers interested in learning and applying it within the classroom. It is intended that this work could motivate the teacher to improve his professional practice, breaking up with the actual classroom environment, based essentially on lectures and recitation classes, and through a continuous work of study and reflection, he could turn Physics teaching more efficient at the High School, since a significant portion of the students has shown little or none interest in studying Physics. Keywords: EJS. Easy Java Simulations. Physics Teaching. Teacher Preparation. Physics SimulationO objetivo deste trabalho é apresentar a ferramenta de simulação Easy Java Simulations (EJS), criada por Francisco Esquembre, e mostrar ao professor do Ensino Médio, através de alguns exemplos e de um guia básico sobre o EJS, como ele pode usá-la para preparar atividades de aprendizagem diferenciadas aos seus alunos. Faz-se uma análise da potencialidade da ferramenta EJS e apresenta-se todo o procedimento básico e necessário para a construção de uma simulação, desde o modelo matemático usado para modelar a evolução do sistema físico em estudo, até a preparação da interface gráfica que permite a visualização dos elementos gráficos. Como produto final da dissertação do Mestrado Profissional, apresenta-se um guia básico do EJS para aquele professor que estiver disposto e motivado em aprender os rudimentos do EJS e aplicá-los em sala de aula. Espera-se que este trabalho seja um convite para o professor melhorar a sua prática profissional, rompendo-se com uma formação ambiental, de caráter repetitivo, e que, a partir de um trabalho contínuo de estudo e de reflexão, ele possa tornar o Ensino de Física no Ensino Médio eficiente, já que uma parcela significativa dos alunos demonstra pouco, ou nenhum, interesse pelo estudo de Física

Propafenone in complex anti-recurrent therapy of persistent atrial fibrillation

Effectiveness and safety of Class IС antiarrhythmic agent, propafenone (Propanorm, PRO. MED. CS Praha a.s., Czech Republic), was studied inpatients with persistent atrial fibrillation (PAF) after sinus rhythm conversion, during long-term ant-recurrent treatment. The study included 30 men and women; mean age 57, 97± 1, 2 years. PAF was caused by essential arterial hypertension, or its combination with stable coronary heart disease. To treat PAF paroxysms, propanorm was administered in the loading dose of 600 mg, continued by anti-recurrent therapy (450 mg/d for 12 months). All participants also received ACE inhibitor lisinopril (Dapril, PRO. MED. CS Praha a.s., Czech Republic). During anti-recurrent propanorm therapy (450 mg/d), no recurrent AF paroxysms were registered in 63, 3 % of the patients; paroxysm frequency reduced in 23, 3 %; paroxysms remained frequent in 13, 3 %. No adverse events were registered. Twelve-month propanorm and dapril treatment was associated with significant improvements in intracardiac hemodynamics and chronic heart failure functional class, as early as by Month 6

Crystal Structure of a Homoleptic Zinc(II) Complex Based on Bis­(3,5-Diiso­propyl­pyrazol-1-yl)Acetate

Deprotonation of the methyl­ene group in bis­(3,5-diiso­propyl­pyrazol-1-yl)methane with nBuLi and reaction with carbon dioxide yields lithium bis­(3,5-diiso­propyl­pyrazol-1-yl)acetate (1). Treatment of 1 with ZnCl2 results in the com­pound bis­[bis­(3,5-diiso­propyl­pyrazol-1-yl)acetato]­zinc(II), [Zn(C20H31N4O2)2] (2), whose structure has monoclinic (P21/c) symmetry. The ZnII ion resides on an inversion center and is coordinated by two bis­(3,5-diiso­propyl­pyrazol-1-yl)acetate (bdippza) ligands. Each ligand facially coordinates the zinc center via κ3N,N′,O coordination modes to form a distorted octa­hedral complex with four pyrazole N atoms in the basal plane and two carboxyl­ate O atoms in the axial sites

Examining the Impact of Steric and Electronic Variation in N\u3csub\u3e2\u3c/sub\u3eS Scorpionate Ligands on the Properties of Zinc(II) and Cadmium(II) Complexes

A series of LZn(II)Br (1–4) and LCd(II)Cl complexes (9–11) has been prepared by the reaction of metal halide precursors with the lithium salts of the N2S− ligands bis(3,5-diisopropylpyrazol-1-yl)dithioacetate (L1), bis(3,5-di-tert-butylpyrazol-1-yl)dithioacetate (L2), N-phenyl-2,2-bis(3,5-diisopropylpyrazol-1-yl)thioacetamide (L3) and N-phenyl-2,2-bis(3,5-di-tert-butylpyrazol-1-yl)thioacetamide (L4). Characterization by X-ray crystallography and DOSY NMR studies indicate that LZnBr complexes 1–4 are mononuclear both in the solid state and in solution. Steric differences between ligands L1–L4 result in distortion from an ideal tetrahedral geometry for each complex, with the degree of distortion depending on the bulk of the ligand substituents. In contrast, the related complex L3CdCl was shown by X-ray crystallography to dimerize in the solid state to form the chloride-bridged five-coordinate complex [L3CdCl]2 (10). Despite 10 having a dinuclear structure in the solid state, DOSY NMR studies indicate 9–11 exist as mononuclear LCdCl species in solution. In addition, Zn(II) cyanide complexes of the form LZnCN [L = L1 (5), L3 (7), L4 (8)] have been characterized and the X-ray structure of 8 determined. Moreover, density functional theory calculations have been conducted which yield important insight into the bonding in 1–4 and 5–8 and the electronic impact of ligands L1–L4 on the zinc(II) ion and its ability to function as a Lewis acid catalyst

General Approach for Engineering Small-Molecule-Binding DNA Split Aptamers

Here we report a general method for engineering three-way junction DNA aptamers into split aptamers. Split aptamers show significant potential for use as recognition elements in biosensing applications, but reliable methods for generating these sequences are currently lacking. We hypothesize that the three-way junction is a “privileged architecture” for the elaboration of aptamers into split aptamers, as it provides two potential splitting sites that are distal from the target binding pocket. We propose a general method for split aptamer engineering that involves removing one loop region, then systematically modifying the number of base pairs in the remaining stem regions in order to achieve selective assembly only in the presence of the target small molecule. We screen putative split aptamer sequence pairs using split aptamer proximity ligation (StAPL) technology developed by our laboratory, but we validate that the results obtained using StAPL translate directly to systems in which the aptamer fragments are assembling noncovalently. We introduce four new split aptamer sequences, which triples the number of small-molecule-binding DNA split aptamers reported to date, and the methods described herein provide a reliable route for the engineering of additional split aptamers, dramatically advancing the potential substrate scope of DNA assembly based biosensors