Structure and denaturation of 4-chlorobenzoyl coenzyme A dehalogenase from Arthrobacter sp. strain TM-1

The secondary structure of the trimeric protein 4-chlorobenzoyl coenzyme A dehalogenase from Arthrobacter sp. strain TM-1, the second of three enzymes involved in the dechlorination of 4-chlorobenzoate to form 4-hydroxybenzoate, has been examined. E(mM) for the enzyme was 12.59. Analysis by circular dichroism spectrometry in the far uv indicated that 4-chlorobenzoyl coenzyme A dehalogenase was composed mostly of alpha-helix (56%) with lesser amounts of random coil (21%), beta-turn (13%) and beta-sheet (9%). These data are in close agreement with a computational prediction of secondary structure from the primary amino acid sequence, which indicated 55.8% alpha-helix, 33.7% random coil and 10.5% beta-sheet; the enzyme is, therefore, similar to the 4-chlorobenzoyl coenzyme A dehalogenase from Pseudomonas sp. CBS-3. The three-dimensional structure, including that of the presumed active site, predicted by computational analysis, is also closely similar to that of the Pseudomonas dehalogenase. Study of the stability and physicochemical properties revealed that at room temperature, the enzyme was stable for 24 h but was completely inactivated by heating to 60 degrees C for 5 min; thereafter by cooling at 1 degrees C min(-1) to 45 degrees C, 20.6% of the activity could be recovered. Mildly acidic (pH 5.2) or alkaline (pH 10.1) conditions caused complete inactivation, but activity was fully recovered on returning the enzyme to pH 7.4. Circular dichroism studies also indicated that secondary structure was little altered by heating to 60 degrees C, or by changing the pH from 7.4 to 6.0 or 9.2. Complete, irreversible destruction of, and maximal decrease in the fluorescence yield of the protein at 330-350 nm were brought about by 4.5 M urea or 1.1 M guanidinium chloride. Evidence was obtained to support the hypothetical three-dimensional model, that residues W140 and W167 are buried in a non-polar environment, whereas W182 appears at or close to the surface of the protein. At least one of the enzymes of the dehalogenase system (the combined 4-chlorobenzoate:CoA ligase, the dehalogenase and 4-hydroxybenzoyl coenzyme A thioesterase) appears to be capable of association with the cell membrane.

O Instituto das Súmulas Vinculantes e sua cogente alteração legislativa: a análise do verbete nº 13

O Supremo Tribunal Federal entregou ao ordenamento jurídico brasileiro, em 21 de agosto de 2008, a súmula vinculante nº 13. O referido verbete trata da vedação a nomeações de cônjuge, companheiro ou parente em linha reta, colateral ou por afinidade até o terceiro grau, no âmbito da administração pública direta e indireta, em todas as esferas. Antes da vigência da súmula vinculante nº 13, o nepotismo era praticado de forma nebulosa, tendo em vista a ausência de uma fiscalização eficaz e eficiente. Os Estados e Municípios, através de legislação própria, buscaram o combate a essa prática em momento anterior à edição do verbete, o país carecia de uma regra geral. A partir do início da vigência da súmula vinculante nº 13, o que se verificou, no âmbito da administração pública brasileira, como será demonstrado adiante, foram diversas exonerações de servidores por simples suposição de que determinada situação jurídica configuraria nepotismo, cenário totalmente contrário àquele então proposto.. O STF manifesta-se face aos casos concretos apenas em sede de reclamação. Têm-se, atualmente, uma situação de grave insegurança jurídica, onde servidores públicos não sabem se podem ou não ser nomeados ou se podem continuar exercendo suas funções. O presente exame, pautado no direito comparado e em estudo de casos, analisou algumas situações hipotéticas que, supostamente, configurariam nepotismo, e outras já decididas pela Suprema Corte e propõe uma alteração de natureza legislativa ao instituto das súmulas vinculantes: a criação de incisos a incluídos no corpo do enunciado após cada decisão em sede de reclamação, cujos efeitos não possuem efeito vinculante. Dessa forma, a administração pública direta e indireta poderá aplicar a súmula vinculante nº 13 de forma eficaz, sem interpretações equivocadas, de modo a permitir uma sintonia entre a segurança jurídica e a moralidade.

Formação contínua de professores em Educação Sexual: percepções de professores sobre as acções de formação e factores que têm influenciado a sua prática pedagógica: um contributo para a efectiva implementação da Educação Sexual nos Ensinos Básico - 2º e 3º Ciclos - e Secundários

Agostinho Ribeiro

Geometria com Sketchpad tm para o Ensino Secundário

Pedro Manuel Augusto

Estudo imuno-histoquímico da presença de miofibroblastos e da expressão do fator transformador de crescimento-beta1, interferon gama, metaloproteinase de matriz 13 e indutor de metaloproteinases de matriz em lesões odontogênicas epiteliais

Myofibroblasts are cells that exhibit a hybrid phenotype, sharing the morphological characteristics of fibroblasts and smooth muscle cells, which is acquired during a process called differentiation. These cells then start to express -SMA, a marker that can be used for their identification. Studies suggest that myofibroblasts are related to the aggressiveness of different tumors and that TGF-1 and IFN- play a role in myofibroblast differentiation, stimulating or inhibiting this differentiation, respectively. The objective of this study was to investigate the role of myofibroblasts in epithelial odontogenic tumors, correlating the presence of these cells with the aggressiveness of the tumor. Immunohistochemistry was used to evaluate the expression of TGF-1 and IFN- in myofibroblast differentiation, as well as the expression of MMP-13, which is activated by myofibroblasts, and of EMMPRIN (extracellular matrix metalloproteinase inducer) as a precursor of this MMP. The sample consisted of 20 solid ameloblastomas, 10 unicystic ameloblastomas, 20 odontogenic keratocysts, and 20 adenomatoid odontogenic tumors. For evaluation of myofibroblasts, anti- -SMA-immunoreactive cells were quantified in connective tissue close to the epithelium. Immunoexpression of TGF-1, IFN-, MMP-13 and EMMPRIN was evaluated in the epithelial and connective tissue components, attributing scores of 0 to 4. The results showed a higher concentration of myofibroblasts in solid ameloblastomas (mean of 30.55), followed by odontogenic keratocysts (22.50), unicystic ameloblastomas (20.80), and adenomatoid odontogenic tumors (19.15) (p=0.001). No significant correlation between TGF-1 and IFN- was observed during the process of myofibroblast differentiation. There was also no correlation between the quantity of myofibroblasts and MMP-13 expression. Significant correlations were found between MMP-13 and TGF-1 (r=0.087; p=0.011), between MMP- 13 and IFN- (r=0.348; p=0.003), as well as between EMMPRIN and MMP-13 (r=0.474; p<0.001) and between EMMPRIN and IFN- (r=0.393; p=0.001). The higher quantity of myofibroblasts observed in solid ameloblastomas, odontogenic keratocysts and unicystic ameloblastomas suggests that these cells are one of the factors responsible for the more aggressive biological behavior of these tumors, although the myofibroblast population was not correlated with TGF-1, IFN-, MMP-13 or EMMPRIN. The correlation between MMP- 13 and TGF-1 suggests that the latter induces the expression of this metalloproteinase. The present results also support the well-established role of EMMPRIN as an inducer of MMP-13. Furthermore, the relationship between EMMPRIN and IFN- and between MMP-13 and IFN- suggests synergism in the antifibrotic effect of these markers

Estudo de ilhas de calor no município de Piratininga/SP, por meio de dados orbitais do landsat 5 sensor tm

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Influência da velocidade de deslizamento no desgaste do par tribológico ferro fundido cinzento (MC 12 e MC 13) - ferro fundido cinzento centrifugado

Pós-graduação em Engenharia Mecânica - FEG

Tm-afm nonlinear motion control with robustness analysis to parametric errors in the control signal determination

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Cri-an-ça: a criatividade, a infância e a imaginação expressadas no desenho (porque os adultos têm sempre necessidade de explicações detalhadas)

O interesse por esta temática de trabalho surgiu a partir de um estudo realizado em minha iniciação científica, que tem por título “Ação, Câmera, Luz: Entre imagens e olhares – experiência de infâncias e montagens” desenvolvido no Departamento de Educação do Instituto de Biociências, localizado na Universidade Estadual Paulista – UNESP/Rio Claro. Como o próprio título sugere, ela tem por principal objetivo inverter a lógica da conhecida frase: “Luz, Câmera, Ação”. Este trabalho, ao inverter a ordem dos fatores, busca ver se ao deixarmos a ação das crianças livre, o que se produziria seria algo mais verdadeiro, mais significativo, de fato. O que a ausência de intencionalidade geraria aos produtores de imagens. A partir de então, comecei a imaginar outro tipo de produção de imagens, não mais com câmeras fotográficas e filmadoras, mas de próprio punho. Portanto, este trabalho tem por objetivo analisar as crianças, e suas realidades através do que elas mesmas nos dizem e nos mostram em seu dia a dia por meio de seus desenhos. Os desenhos utilizados foram retirados de uma instituição de ensino não formal da cidade de Rio Claro, e entendidos como documentos. A pesquisa traz também um aporte teórico com as concepções sobre desenho infantil de alguns teóricos, como Lowenfel, Greig, La Pastina, Vigotski entre outros

Preanesthetic assessment data do not influence the time for tracheal intubation with Airtraq (TM) video laryngoscope in obese patients

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Adsorption of NO on the Rh-13, Pd-13, Ir-13, and Pt-13 Clusters: A Density Functional Theory Investigation

The adsorption of NO on transition-metal (TM) surfaces has been widely studied by experimental and theoretical techniques; however, our atomistic understanding of the interaction of nitrogen monoxide (NO) with small TM clusters is far from satisfactory, which compromises a deep understanding of real catalyst devices. In this study, we report a density functional theory study of the adsorption properties of NO on the TM13 (TM = Rh, Pd, Ir, Pt) clusters employing the projected augmented wave method. We found that the interaction of NO with TM13 is much more complex than that for NO/TM(111). In particular, for low symmetry TM13 clusters, there is a strong rearrangement of the electronic charge density upon NO adsorption and, as a consequence, the adsorption energy shows a very complex dependence even for adsorption sites with the same local effective coordination. We found a strong enhancement of the binding energy of NO to the TM13 clusters compared with the TM(111) surfaces, as the antibonding NO states are not occupied for NO/TM13, and the general relationship based on the d-band model between adsorption energy and the center of gravity of the occupied d-states does not hold for the studied TM13 clusters, in particular, for clusters with low symmetry. In contrast with the adsorption energy trends, the geometric NO/TM13 parameters and the vibrational N-O frequencies for different coordination sites follow the same trend as for the respective TM(111) surfaces, while the changes in the frequencies between different surfaces and TM13 clusters reflect the strong NO-TM13 interaction.

STRUCTURAL CHARACTERIZATION OF CANOPIES OF Eucalyptus spp. USING RADIOMETRIC DATA FROM TM/Landsat 5

Empirical approaches and, more recently, physical approaches, have grounded the establishment of logical connections between radiometric variables derived from remote data and biophysical variables derived from vegetation cover. This study was aimed at evaluating correlations of dendrometric and density data from canopies of Eucalyptus spp., as collected in Capao Bonito forest unit, with radiometric data from imagery acquired by the TM/Landsat-5 sensor on two orbital passages over the study site (dates close to field data collection). Results indicate that stronger correlations were identified between crown dimensions and canopy height with near-infrared spectral band data (rho(s)4), irrespective of the satellite passage date. Estimates of spatial distribution of dendrometric data and canopy density (D) using spectral characterization were consistent with the spatial distribution of tree ages during the study period. Statistical tests were applied to evaluate performance disparities of empirical models depending on which date data were acquired. Results indicated a significant difference between models based on distinct data acquisition dates.

Platinum-Based Nanoalloys PtnTM55-n (TM=Co, Rh, Au): A Density Functional Theory Investigation

Structural and electronic properties of the PtnTM55-n (TM = Co, Rh, Au) nanoalloys are investigated using density functional theory within the generalized gradient approximation and employing the all-electron projected augmented wave method. For TM = Co and Rh, the excess energy, which measures the relative energy stability of the nanoalloys, is negative for all Pt compositions. We found that the excess energy has similar values for a wide range of Pt compositions, i.e., n = 20-42 and n = 28-42 for Co and Rh, respectively, with the core shell icosahedron-like configuration (n = 42) being slightly more stable for both Co and Rh systems because of the larger release of the strain energy due to the smaller atomic size of the Co and Rh atoms. For TM = Au, the excess energy is positive for all compositions, except for n = 13, which is energetically favorable due to the formation of the core-shell structure (Pt in the core and Au atoms at the surface). Thus, our calculations confirm that the formation of core-shell structures plays an important role to increase the stability of nanoalloys. The center of gravity of the occupied d-states changes almost linearly as a function of the Pt composition, and hence, based on the d-band model, the magnitude of the adsorption energy of an adsorbate can be tuned by changing the Pt composition. The magnetic moments of PtnCo55-n decrease almost linearly as a function of the Pt composition; however, the same does not hold for PtRh and PtAu. We found an enhancement of the magnetic moments of PtRh by a few times by increasing Pt composition, which we explain by the compression effects induced by the large size of the Pt atoms compared with the Rh atoms.