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Os missionários da educa??o e o Instituto Ponte Nova da Bahia
Nascimento,Ester Fraga Villas-B?as Carvalho do;
Revista Lusófona de Educa??o , 2005,
Abstract: over one hundred years 1871 to 1971 - the missionaries of brazil?s central mission, who belonged to the presbyterian church of the north of the united states (pcusa), left bahia and organised churches, schools and hospitals in their area of influence - segipe, mato grosso, goiás and north minas gerais. having analysed the reality of the brazilian hinterland, william alfred waddell proposed a new kind of educational institution, different from the s?o paulo mackenzie college: a rural secondary school offering courses for primary school teachers, for pastors, for assistant nurses and agrarian technicians. ipn, as the instituto ponte nova came to be known, was established by the mission in 1906, which organised and sponsored, apart from the school, a church and a school for assistant nurses, the first of its kind in bahia, beside the grace memorial hospital. the success of that institutional complex, integrating religion, education and health, led the mission to organise a project named ?escolas ponte nova? [ponte nova schools]. in 1926 the mission had already opened seven schools following the proposed model and four hospitals in the area under their jurisdiction. in 1926, there existed agricultural schools in buriti and cáceres - mato grosso; jataí and planaltina - goiás. in this city, a hospital was built. in rio verde, goiás, a school of nursing and a hospital had been organized. in araguaia, mato grosso, a hospital hospital was built and in anápolis, goiás, apart from the school, a hospital was built.
Influence of the RelA Activity on E. coli Metabolism by Metabolite Profiling of Glucose-Limited Chemostat Cultures
Sónia Carneiro,Silas G. Villas-B?as,Eugénio C. Ferreira,Isabel Rocha
Metabolites , 2012, DOI: 10.3390/metabo2040717
Abstract: Metabolite profiling of E. coli W3110 and the isogenic D relA mutant cells was used to characterize the RelA-dependent stringent control of metabolism under different growth conditions. Metabolic profiles were obtained by gas chromatography–mass spectrometry (GC-MS) analysis and revealed significant differences between E. coli strains grown at different conditions. Major differences between the two strains were assessed in the levels of amino acids and fatty acids and their precursor metabolites, especially when growing at the lower dilution rates, demonstrating differences in their metabolic behavior. Despite the fatty acid biosynthesis being the most affected due to the lack of the RelA activity, other metabolic pathways involving succinate, lactate and threonine were also affected. Overall, metabolite profiles indicate that under nutrient-limiting conditions the RelA-dependent stringent response may be elicited and promotes key changes in the E. coli metabolism.
Alkylation or Silylation for Analysis of Amino and Non-Amino Organic Acids by GC-MS?
Silas G. Villas-B?as,Kathleen F. Smart,Subathira Sivakumaran,Geoffrey A. Lane
Metabolites , 2011, DOI: 10.3390/metabo1010003
Abstract: Gas chromatography–mass spectrometry (GC-MS) is a widely used analytical technique in metabolomics. GC provides the highest resolution of any standard chromatographic separation method, and with modern instrumentation, retention times are very consistent between analyses. Electron impact ionization and fragmentation is generally reproducible between instruments and extensive libraries of spectra are available that enhance the identification of analytes. The major limitation is the restriction to volatile analytes, and hence the requirement to convert many metabolites to volatile derivatives through chemical derivatization. Here we compared the analytical performance of two derivatization techniques, silylation (TMS) and alkylation (MCF), used for the analysis of amino and non-amino organic acids as well as nucleotides in microbial-derived samples. The widely used TMS derivatization method showed poorer reproducibility and instability during chromatographic runs while the MCF derivatives presented better analytical performance. Therefore, alkylation (MCF) derivatization seems to be preferable for the analysis of polyfunctional amines, nucleotides and organic acids in microbial metabolomics studies.
Efeito da co-dopagem com Pr e Mn nas propriedades elétricas de Sr-LaAlO3
Villas-B?as, L.A.;De Souza, D.P.F.;
Matéria (Rio de Janeiro) , 2010, DOI: 10.1590/S1517-70762010000100002
Abstract: in this work, the electrical properties of laalo3 doped with strontium (sr) and co-doped with praseodymium (pr) and manganese (mn) were investigated. doped-laalo3 powders were prepared by oxide mixture through successive calcinations. samples, obtained via isostatic pressing, were sintered at 1600 °c in air during 6 h of soaking time. sintered samples were characterized by x-ray diffraction, scanning electron microscopy and impedance spectroscopy. conductivity measurements show that sr-doped-laalo3 is a p-type semiconductor at high oxygen partial pressures, but becomes a pure oxide-ion conductor at low oxygen partial pressures. a significant difference in electrical conductivity of pr- and mn-co-doping on the b- and a-site, respectively, in sr-laalo3 was observed. the pr-co-doping increased the grain conductivity in oxidizing condition and the activation energy remained constant. the mn co-doping generated samples with high electronic conductivity.
Achados oculares em pacientes com mucopolissacaridoses
Villas-B?as, Flávia Silva;Fernandes Filho, Dilson José;Acosta, Angelina Xavier;
Arquivos Brasileiros de Oftalmologia , 2011, DOI: 10.1590/S0004-27492011000600010
Abstract: purpose: the objective of this study was to determine the prevalence and severity of ocular complications in patients with mucopolysaccharidosis (mps). methods: twenty-nine patients with diagnosis of mucopolysaccharidosis were studied. age, gender, visual acuity, presence of strabismus, refractive error, fundus examination, intraocular pressure, central corneal thickness and ocular echography were assessed for each individual. results: there were three patients with mps i (12%), eleven patients with mps ii (37.9%), one patient with mps iii (3.4%) and fourteen patients with mps vi (48.3%). mean age was 9.5 years (ranged from 1.2 to 20 years, dp 5.5). refraction was available in 26 patients, from which 88.5% (23 patients) were hyperopic, and 53.8% (14 patients) presented astigmatism. best corrected visual acuity was available in 18 patients and the mean was 0.45 logmar (dp 0.68). the mean spherical equivalent was +3.57 d (sd 2.46) and intraocular pressure was 17 mmhg (sd 3.9). the most common findings were: eyelid thickening in 24.1% (7 patients); corneal opacity in 55.2% of cases (16 patients); optic nerve atrophy in 23.1% (6 patients); and radial folds in the retina in 24% (7 patients). the fundus was examined in 26 out of 29 patients because corneal opacity avoided the exam in 3 of them. the average thickness of the complex sclera-retina-choroid (src was 1.78 mm (sd 0.51). conclusion: the most prominent ophthalmologic findings were eyelid thickening, decreased visual acuity, high hyperopia, corneal opacity, perimacular radial folds in the retina and optic nerve atrophy.
Biomicroscopia ultra-s?nica em esclerectomia profunda: relato de caso
Villas-B?as, Flávia;Allemann, Norma;Morales, Maira Saad Avila;Omi, Carlos Akira;
Arquivos Brasileiros de Oftalmologia , 2008, DOI: 10.1590/S0004-27492008000300026
Abstract: case report of a woman with the diagnosis of primary open-angle glaucoma who was submitted to a successful surgical procedure of deep sclerectomy in the right eye. in the postoperative period, at month 3, the surgical procedure was evaluated with ultrasound biomicroscopy (ubm) utilizing two distinct equipments (ubm 840-zeiss; ubm-vumax-sonomed), with 50-mhz transducers. the diagnostic method of ultrasound biomicroscopy can be utilized as a non invasive method to evaluate the internal architecture of the eye at the topography of deep sclerectomy. it allows to identify the anterior segment structures, their anatomical relationship, and also the intact trabecular-descemet membrane and the intrascleral space. ultrasound biomicroscopy showed to be useful in evaluating postoperative status of the surgical procedure.
Hidrata??o do óxido de magnésio em presen?a de alumina hidratável
Salom?o, R.;Villas-B?as, M. C. O.;Pandolfelli, V. C.;
Ceramica , 2010, DOI: 10.1590/S0366-69132010000300015
Abstract: the substitution of calcium aluminate cement by hydratable aluminas in mgo-containing refractory castables can afford several benefits for these materials mechanical properties and refractoriness. nevertheless, the way that hydratable aluminas affects mgo hydration and its consequences were not yet systemically explored. in the present work, four sources of magnesia and alumina were combined at different ratios and hydrated simultaneously. they were investigated by x-ray diffraction, thermogravimetry and apparent volumetric expansion measurements. it was found that the magnesia/alumina ratio and the differences of reactivity of each raw material can greatly affect both hydration processes, generating different hydrated compounds. it was also verified that this combination can be suitably used as powerful mgo anti-hydration technique.
Mecanismo de centraliza??o: da insuficiência placentária à adapta??o circulatória fetal
Villas-B?as, Juliana Marques Sim?es;Maestá, Izildinha;Consonni, Marcos;
Revista Brasileira de Ginecologia e Obstetrícia , 2008, DOI: 10.1590/S0100-72032008000700008
Abstract: the application and development of obstetric dopplervelocimetry provide a basis for the investigation of placental insufficiency and demonstrate the dynamic behavior of fetal circulation during hypoxia. in clinical practice, assessing hemodynamics in three vascular regions involved in pregnancy, namely the uterine, umbilical and middle cerebral arteries, has become routine. roughly, the cerebral artery expresses the balance between uterine artery oxygen supply and umbilical artery oxygen uptake. currently, when such balance is unfavorable, the fetal cardiac reserve is investigated by assessing the venous duct. however, determining and interpreting vascular resistance indexes is not an easy task. the starting point is to know the physiopathology of placental insufficiency and fetal circulatory adaptation through which doppler confirmed its role in the assessment of fetal well-being.
Biodegradability potential of two experimental landfills in Brazil
Vazoller Rosana Filomena,Gomes Luciana Paulo,Baldochi Viviana Maria Zanta,Villas-B?as Denise Maria Fortes
Brazilian Journal of Microbiology , 2001,
Abstract: Solid wastes anaerobic biodegradability, methane production potential and microbiological composition of two experimental sanitary landfills in Brazil, running for one year, were evaluated. The two landfills showed a similar organic matter stabilization during the methane production phase, despite the high heterogeneity of the solid wastes. Both landfills presented the same level of methane (around 91.5 L CH4 / kg Volatile Total Solids) and organic acids, mainly acetic and butyric acids, in the leachate. Bacterial isolates belonged to genera Megasphaera, Selenomonas, Methanobacterium, Methanobrevibacter and Methanosarcina.
The Growth and Survival of Mycobacterium smegmatis Is Enhanced by Co-Metabolism of Atmospheric H2
Chris Greening, Silas G. Villas-B?as, Jennifer R. Robson, Michael Berney, Gregory M. Cook
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0103034
Abstract: The soil bacterium Mycobacterium smegmatis is able to scavenge the trace concentrations of H2 present in the atmosphere, but the physiological function and importance of this activity is not understood. We have shown that atmospheric H2 oxidation in this organism depends on two phylogenetically and kinetically distinct high-affinity hydrogenases, Hyd1 (MSMEG_2262-2263) and Hyd2 (MSMEG_2720-2719). In this study, we explored the effect of deleting Hyd2 on cellular physiology by comparing the viability, energetics, transcriptomes, and metabolomes of wild-type vs. Δhyd2 cells. The long-term survival of the Δhyd2 mutant was significantly reduced compared to the wild-type. The mutant additionally grew less efficiently in a range of conditions, most notably during metabolism of short-chain fatty acids; there was a twofold reduction in growth rate and growth yield of the Δhyd2 strain when acetate served as the sole carbon source. Hyd1 compensated for loss of Hyd2 when cells were grown in a high H2 atmosphere. Analysis of cellular parameters showed that Hyd2 was not necessary to generate the membrane potential, maintain intracellular pH homeostasis, or sustain redox balance. However, microarray analysis indicated that Δhyd2 cells were starved for reductant and compensated by rewiring central metabolism; transcripts encoding proteins responsible for oxidative decarboxylation pathways, the urea cycle, and ABC transporter-mediated import were significantly more abundant in the Δhyd2 mutant. Metabolome profiling consistently revealed an increase in intracellular amino acids in the Δhyd2 mutant. We propose that atmospheric H2 oxidation has two major roles in mycobacterial cells: to generate reductant during mixotrophic growth and to sustain the respiratory chain during dormancy.
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