Melatonin and its kynurenin-like oxidation products affect the microbicidal activity of neutrophils

Activated phagocytes oxidize the hormone melatonin to N-1-acethyl-N-2-formyl-5-methoxykynuramine (AFMK) in a superoxide anion- and myeloperoxidase-dependent reaction. We examined the effect of melatonin, AFMK and its deformylated-product N-acetyl-5-methoxykynuramine (AMK) on the phagocytosis, the microbicidal activity and the production of hypochlorous acid by neutrophils. Neither neutrophil and bacteria viability nor phagocytosis were affected by melatonin, AFMK or AMK. However these compounds affected the killing of Staphylococcus aureus. After 60 min of incubation, the percentage of viable bacteria inside the neutrophil increased to 76% in the presence of 1 mM of melatonin, 34% in the presence of AFMK and 73% in the presence of AMK. The sole inhibition of HOCl formation, expected in the presence of myeloperoxidase substrates, was not sufficient to explain the inhibition of the killing activity. Melatonin caused an almost complete inhibition of HOCl formation at concentrations of up to 0.05 mM. Although less effective, AMK also inhibited the formation of HOCl However, AFMK had no effect on the production of HOCl These findings corroborate the present view that the killing activity of neutrophils is a complex phenomenon, which involves more than just the production of reactive oxygen species. Furthermore, the action of melatonin and its oxidation products include additional activities beyond their antioxidant property. The impairment of the neutrophils' microbicidal activity caused by melatonin and its oxidation products may have important clinical implications, especially in those cases in which melatonin is pharmacologically administered in patients with infections. (c) 2005 Elsevier SAS. All rights reserved.

Development and validation of a stability-indicative agar diffusion assay to determine the potency of linezolid in tablets in the presence of photodegradation products

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

Prospective study for the development of emulsion systems containing natural oil products

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Screening for antimicrobial activity of natural products using a microplate photometer

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

An Intelligent System for Petroleum Well Drilling Cutting Analysis

Cutting analysis is a important and crucial task task to detect and prevent problems during the petroleum well drilling process. Several studies have been developed for drilling inspection, but none of them takes care about analysing the generated cutting at the vibrating shale shakers. Here we proposed a system to analyse the cutting's concentration at the vibrating shale shakers, which can indicate problems during the petroleum well drilling process, such that the collapse of the well borehole walls. Cutting's images are acquired and sent to the data analysis module, which has as the main goal to extract features and to classify frames according to one of three previously classes of cutting's volume. A collection of supervised classifiers were applied in order to allow comparisons about their accuracy and efficiency. We used the Optimum-Path Forest (OPF), Artificial Neural Network using Multi layer Perceptrons (ANN-MLP), Support Vector Machines (SVM) and a Bayesian Classifier (BC) for this task. The first one outperformed all the remaining classifiers. Recall that we are also the first to introduce the OPF classifier in this field of knowledge. Very good results show the robustness of the proposed system, which can be also integrated with other commonly system (Mud-Logging) in order to improve the last one's efficiency.

Flexural Test on Recycled Polystyrene

In socio-environmental scenario increased the nature resources concern beyond products and subproducts reuse. Recycling is the approach for a material or energy reintroducing in productive system. This method allows the reduction of garbage volume dumped in environment, saving energy and decreasing the requirement of natural resources use. In general, the ending of expanded polystyrene is deposited sanitary landfills or garbage dumps without control that take large volume and spreads easily by aeolian action, with consequently environmental pollution, however, the recycling avoids their misuse and the obtainment from petroleum is reduced. This work recycled expanded polystyrene via merger and/or dissolution by solvents for the production of integrated circuits boards. The obtained material was characterized in flexural mode according to ASTM D 790 and results were compared with phenolite, traditionally used. Specimens fractures were observed by electronic microscopy scanning in order to establish patterns. Expanded Polyestirene recycled as well as phenolite were also thermo analyzed by TGA and DSC. The method using dissolution produced very brittle materials. The method using merger showed no voids formation nor increased the brittleness of the material. The recycled polystyrene presented a strength value significantly lower than that for the phenolite. (C) 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of ICM11

Preparação de resinas de poliuretana à base de óleo de mamona e dietanolamina

The aim of this work was the preparation of polyols from reactions between castor oil and dietanolamine to increase the hydroxyl content and the network degree in the products to application in electronic devices. The polyols and the mixtures obtained were characterized by nuclear magnetic ressonance. Castor oil (CO) is a natural triglyceride - based polyol possessing hydroxyl groups, which allow several reactions that produce many different products. Among them are the polyurethanes (PU), which have been considered an ideal product for the covering of electricelectronic circuits, due to their excellent electrical, shock-absorbing, solvents resistance and hydrolytic stability properties. About 90% of the fatty acids present in the castor oil are ricinoleic acid (12-hydroxyoleic acid), while the remaining 10% correspond to non-hydroxylated fatty acids, mainly linoleic and oleic acids. The chemical analysis of castor oil indicates a hydroxyl number of 2.7. In this work, a polyol was obtained by the reaction of the CO with diethanolamine (DEA), in order to elevate the hydroxyl value from 160 to 230 or to 280 mgKOH/g, and characterized by nuclear magnetic resonance (NMR) 1H and 13C (Mercury 200). The polyadition of the resulting polyol with isophorone diisocianate (IPDI) was carried out at 60°C, and the reaction kinetics was followed by rheological measurements in a Haake RS150 rheometer. The electrical properties were determined in a HP LCR Meter 4262A, at 1.0 Hz and 10.0 KHz. The chemical analysis showed that the polyols obtained presented hydroxyl number from 230 to 280 mgKOH/g. The polyadition reaction with IPDI produced polyurethane resins with the following properties: hardness in the range from 45 shore A to 65 shore D (ASTM D2240); a dielectric constant of 3.0, at 25°C (ASTM D150). Those results indicate that the obtained resins present compatible properties to the similar products of fossil origin, which are used nowadays for covering electric-electronic circuits. Therefore, the PUs from castor oil can be considered as alternative materials of renewable source, free from the highly harmful petroleum - derived solvents

Estudo teórico aplicado ao petróleo: estabilidade dos alcenos e recuperação terciária

The present work aims to study the theoretical level of some processes employed in the refining of petroleum fractions and tertiary recovery of this fluid. In the third chapter, we investigate a method of hydrogenation of oil fractions by QTAIM (Quantum Theory of Atoms in Molecules) and thermodynamic parameters. The study of hydrogenation reactions, and the stability of the products formed, is directly related to product improvement in the petrochemical refining. In the fourth chapter, we study the theoretical level of intermolecular interactions that occur in the process of tertiary oil recovery, or competitive interactions involving molecules of non-ionic surfactants, oil and quartz rock where oil is accumulated. Calculations were developed using the semiempirical PM3 method (Parametric Model 3). We studied a set of ten non-ionic surfactants, natural and synthetic origin. The study of rock-surfactant interactions was performed on the surface of the quartz (001) completely hydroxylated. Results were obtained energetic and geometric orientations of various surfactants on quartz. QTAIM was obtained through the analysis of the electron density of interactions, and thus, providing details about the formation of hydrogen bonds and hydrogen-hydrogen systems studied. The results show that the adsorption of ethoxylated surfactants in the rock surface occurs through the hydrogen bonding of the type CH---O, and surfactants derivatives of polyols occurs by OH---O bonds. For structures adsorption studied, the large distance of the surfactant to the surface together with the low values of charge density, indicate that there is a very low interaction, characterizing physical adsorption in all surfactants studied. We demonstrated that surfactants with polar group comprising oxyethylene units, showed the lowest adsorption onto the surface of quartz, unlike the derivatives of polyols

Remoção, por flotação, de óleo em águas produzidas na indústria de petróleo: eficiência e modelagem do processo

The separation oil-water by the use of flotation process is characterized by the involvement between the liquid and gas phases. For the comprehension of this process, it s necessary to analyze the physical and chemical properties command float flotation, defining the nature and forces over the particles. The interface chemistry has an important role on the flotation technology once, by dispersion of a gas phase into a liquid mixture the particles desired get stuck into air bubbles, being conduced to a superficial layer where can be physically separated. Through the study of interface interaction involved in the system used for this work, was possible to apply the results in an mathematical model able to determine the probability of flotation using a different view related to petroleum emulsions such as oil-water. The terms of probability of flotation correlate the collision and addition between particles of oil and air bubbles, that as more collisions, better is the probability of flotation. The additional probability was analyzed by the isotherm of absorption from Freundlich, represents itself the add probability between air bubbles and oil particles. The mathematical scheme for float flotation involved the injected air flow, the size of bubbles and quantity for second, the volume of float cell, viscosity of environment and concentration of demulsifier. The results shown that the float agent developed by castor oil, pos pH variation, salt quantity, temperature, concentration and water-oil quantity, presented efficient extraction of oil from water, up to 95%, using concentrations around 11 ppm of demulsifier. The best results were compared to other commercial products, codified by ―W‖ and ―Z‖, being observed an equivalent demulsifier power between Agflot and commercial product ―W‖ and superior to commercial product ―Z‖

BMMobile: uma linha de produtos para dimensionamento de bombeio mecânico em dispositivos móveis

With the increase of processing ability, storage and several kinds of communication existing such as Bluetooth, infrared, wireless networks, etc.., mobile devices are no longer only devices with specific function and have become tools with various functionalities. In the business field, the benefits that these kinds of devices can offer are considerable, because the portability allows tasks that previously could only be performed within the work environment, can be performed anywhere. In the context of oil exploration companies, mobile applications allow quick actions could be taken by petroleum engineers and technicians, using their mobile devices to avoid potential catastrophes like an unexpected stop or break of important equipment. In general, the configuration of equipment for oil extraction is performed on the work environment using computer systems in desktop platforms. After the obtained configuration, an employee goes to equipment to be configured and perform the modifications obtained on the use desktop system. This management process equipment for oil extraction takes long time and does not guarantee the maintenance in time to avoid problems. With the use of mobile devices, management and maintenance of equipment for oil extraction can be performed in a more agile time once it enables the engineer or technician oil can perform this configuration at the time and place where the request comes for example, near in the oil well where the equipment is located. The wide variety of mobile devices creates a big difficulty in developing mobile applications, since for one application can function in several types of devices, the application must be changed for each specific type of device, which makes the development quite costly. This paper defines and implements a software product line for designing sucker-rod pumping systems on mobile devices. This product line of software, called BMMobile, aims to produce products that are capable of performing calculations to determine the possible configurations for the equipment in the design suckerrod pumping, and managing the variabilities of the various products that can be generated. Besides, this work performs two evaluations. The first evaluation will verify the consistency of the products produced by the software product line. The second evaluation will verify the reuse of some products generated by SPL developed

Caracterização da dinâmica ambiental da região costeira do município de Galinhos, litoral setentrional do Rio Grande do Norte

This doctorate thesis concerning on the Characterization of the Environmental Dynamics of the Coastal Area of the Municipal district of Galinhos, Septentrional Coast of Rio Grande do Norte State, is located in the influence area of the Guamaré Petroliferous Pole, having as general objective the understanding of the active coastal dynamics in the region of Galinhos, whose specific objectives were: To study the variation of the coast line in the decades of 1954, 1967,1988, 1996, 2000, from remote sensing products; To elucidate the hypothesis of the region of Galinhos to have been an old system of islands barriers, using as basic tool the penetration radar in the soil - GPR; To monitor and to characterize the coastal dynamics of the study area starting from monthly data of beach profiles, sedimentological analysis, hydrodynamic data and environmental characterization data; which were used to feed the database of the N-NE network of Environmental Monitoring of Areas under Influence of the Petroliferous Industry;(REDE05/FINEP/CNPq/CTPETRO/ PETROBRAS). This research is justified, of the environmental point of view, by involving the mangrove ecosystem considered one of the most delicated environments of the State. From the viewpoint of the petroleum exploration, the systems of islands barriers are favorable for hydrocarbons reservoirs and, consequently important targets to the oil and gas industry, becoming this region attractive in comparison with similar lithified environments. With the results of the variability study in the position of the coast line in the Municipal district of Galinhos/RN from the analysis of remote sensing images, it was possible to investigate the changes in the coast line in temporal scale; the use of directional filters allowed to emphasize linings in the direction NE and to identify submerged features such as sandwaves. The use of GPR enabled the confirmation of paleochannels existence and thus confirmed the hypothesis that the Galinhos spit was formed from an old system of islands barriers. The results of the granulometric analyses indicated that in the summer period the sediments in the profiles A and B in the foreshore portion were classified with the granulometry of sand with scattered gravel and in the shoreface were constituted by sand, but in the winter period these same morphologic compartments were constituted by sand with sparse gravel and siltic sand respectively. In the profile C, in the summer and in the winter, the shoreface and foreshore compartments presented predominantly constituted by sand with sparse gravel. The hydrodynamic results showed that the largest wave heights were registered in the month of February (62 cm) and the highest period of 1,00 m/s in the month of May, the sense of the coastal currents was kept among the quadrants SW and NW, and the winds coming from NE were predominant. The analysis of the beach profiles demonstrated that in the profile A, although it had occurred erosion and deposition during the monitored months, the morphology of the referred profile was kept constant. In the profiles B and C, there were abrupt changes in the morphology, during the monitored months, having been identified a cyclic pattern in the features of the foreshore zone sometimes forming longitudinal sandy bars and in other times forming berm. These results evidenced, therefore, that studies of this nature are of fundamental importance for the coastal zoning, aiming subsidies to the organs managers in the closing of decisions as for the implantation of enterprises in the area, and for the industry of the petroleum through generation of information that subsidize the implementation and location of petroliferous structures adequate to this environment

Cartografia temporal e análise geoambiental da dinâmica da foz do Rio Piranhas-Açu, regiao de Macau-RN, com base em imagens Landast 5-MT

This work embraces the application of Landsat 5-TM digital images, comprising August 2 1989 and September 22 1998, for temporal mapping and geoenvironmental analysis of the dynamic of Piranhas-Açu river mouth, situated in the Macau (RN) region. After treatment using several digital processing techniques (e.g. colour composition in RGB, ratio of bands, principal component analysis, index methods, among others), it was possible to generate several image products and multitemporal maps of the coastal morphodynamics of the studied area. Using the image products it was possible the identification and characterization of the principal elements of interest (vegetation, soil, geology and water) in the surface of the studied area, associating the spectral characteristics of these elements to that presented by the image products resulting of the digital processing. Thus, it was possible to define different types of soils: Amd, AQd6, SK1 and LVe4; vegetation grouping: open arboreal-shrubby caatinga, closed arborealshrubby caatinga, closed arboreal caatinga, mangrove vegetation, dune vegetation and areas predominately constituted by juremas; geological units: quaternary units beach sediments, sand banks, dune flats, barrier island, mobile dunes, fixed dunes, alluvium, tidal and inundation flats, and sandy facies of the Potengi Formation; tertiary-quaternary units Barreiras Formation grouped to the clayey facies of the Potengi Formation, Macau Formation grouped to the sediments of the Tibau Formation; Cretaceous units Jandaíra Formation; moreover it was to identify the sea/land limit, shallow submersed areas and suspended sediments. The multitemporal maps of the coastal morphodynamics allowed the identification and a semi-quantitative evoluation of regions which were submitted to erosive and constructive processes in the last decade. This semi-quantitative evoluation in association with an geoenvironmental characterization of the studied area are important data to the elaboration of actions that may minimize the possible/probable impacts caused by the implantation of the Polo Gas/Sal and to the monitoring of areas explorated by the petroleum and salt industries

Occurrence of coagulase-positive Staphylococcus in various food products commercialized in Botucatu, SP, Brazil and detection of toxins from food and isolated strains

The aim of this work was to assess the microbiological quality of commercialized desserts, sandwiches and finger food in Botucatu, SP, for human consumption. A total of 172 food samples were analyzed for fecal coliforms and coagulase-positive Staphylococcus and 69 (40.1%) were in disagreement with the standards established by Decree No. 12 (Brazilian Food Sanitation Standard, 2001). Coagulase-positive Staplylococcus was isolated from 26 (15.1%) samples. Toxins were not isolated directly from foods but 27 (54%) coagulase-positive Staphylococcus strains were enterotoxigenic, and toxin type C was the most frequently detected. These results suggest that these products may act as an important vehicle of transmission for well-established pathogens. (c) 2006 Elsevier Ltd. All rights reserved.