Construção de modelos de interação in silico e in vitro do inibidor do tipo Kunitz de Adenanthera pavonina L. para as enzimas cisteínicas e serínicas

Serines proteinases inhibitors (PIs) are widely distributed in nature and are able to inhibit both in vitro and in vivo enzymatic activites. Seed PIs in than leguminous are classified in seven families, Bowman-Birk and Kunitz type families that most studied representing an important role in the first line of defense toward insects pests. Some Kunitz type inhibitors possess activities serine and cysteine for proteinases named bifunctional inhibitor, as ApTKI the inhibitor isolate from seed of Adenanthera pavonina. The A. pavonina inhibitor presenting the uncommon property and was used for interaction studies between proteinases serine (trypsin) and cysteine (papain). In order to determinate the in vitro interaction of ApTKI against enzymes inhibitor purification was carried cut by using chromatographic techniques and inhibition assays. The 3D model of the bifunctional inhibitor ApTKI was constructed SWISS-MODEL program by homology modeling using soybean trypsin inhibitor (STI, pdb:1ba7), as template which presented 40% of identity to A. pavonina inhibitor. Model quality was evaluated by PROCHECK program. Moreover in silico analyzes of formed complex between the enzymes and ApTKI was evaluated by HEX 4.5 program. In vitro results confirmed the inhibitory assays, where the inhibitor presented the ability to simultaneously inhibit trypsin and papain. The residues encountered in the inhibitor model of folder structural three-dimensional that make contact to enzymes target coud explain the specificity pattern against serine and cysteine proteinases

Extração, caracterização estrutural e atividades farmacológicas do olginato obtido da alga marrom Lobophora variegata (Lamouroux) Oliveira Filho, 1977

The alginic acid or alginates are acidic polysaccharides found in brown seaweed widely used in food, cosmetic, medical and pharmaceutical industry. This paper proposes the extraction, chemical characterization and verification of the pharmacological activities of brown seaweed variegata Lobophora . The alginate was extracted from the seaweed Lobophora variegata and part was sulphated for comparative purposes. The native extract showed 42% total sugar, 65% uronic acid, 0,36 % protein and 0% of sulfate, while the sulfate showed 39% , 60%, 0.36% and 27,92 % respectively. The presence of a sulfate group may be observed by the metachromasia with toluidine blue in electrophoresis system and characteristic vibration 1262,34 cm-1 in infrared spectroscopy connections assigned to S = O. We observed the formation of films and beads of native alginate, where more concentrated solution 6% resulted in a thicker and more consistent film. Native alginate showed proliferative activity at concentrations (25 and 50 mcg), (50 mg) and (100 mg) in 3T3 cell line in 24h, 48h and 72h, respectively , as the sulfated (100 mg) in 24 . Also showed antiproliferative or cytotoxic activity in HeLa cells of strain, (25 and 100 mg), (25 and 100 mg) and (25, 50 and 100 mg), to native, now for the sulfate concentrations (100 mg) in 24 (25, 50 and 100 mg) in 48 hours, and (50 and 100 mg ) 72h. For their antioxidant activity, the sulfated alginates have better total antioxidant activity reaching 29 % of the native activity while 7.5 % of activity . For the hydroxyl radical AS showed high inhibition ( between 77-83 % ) in concentrations, but the AN surpassed these numbers in the order of 78-92 % inhibition. The reducing power of AN and AS ranged between 39-82 % . In the method of ferric chelation NA reached 100 % chelating while the AS remained at a plateau oscillating 6.5%. However, in this study , we found alginates with promising pharmacological activities, to use in various industries as an antioxidant / anti-tumor compound

Avaliação da ação bioinseticida de SBTI e vicilina de Erythrina velutina em enzimas digestivas e membrana peritrófica de larvas de Plodia interpunctella (Lepidoptera: Pyralidae)

Plodia interpunctella (Indian meal moth) is a cosmopolitan pest that attacks not only a wide range of stored grain as well other food products. Due to its economic importance several researches have focused in a method with ability to control this pest with few or no damage to the environment. The study of digestive enzymes inhibitors, lectins and chitin-binding proteins, has often been proposed as an alternative to reduce insect damage. In this study we report the major classes of digestive enzymes during larval growth in P. Interpunctella, being those proteinases actives at pH 9.5 and optimum temperature of 50 oC to both larvae of the 3rd instar and pre-pupal stage of development. In vitro and zymogram assays presented the effects of several inhibitors, such as SBTI, TLCK and PMSF to intestinal homogenate of 3rd instar larvae of 62%, 92% and 87% of inhibition and In pre-pupal stage of 87%, 62 % and 55% of inhibition, respectively. Zymograms showed inhibition of two low molecular masses protein bands by TLCK and that in presence of SBTI were retarded. These results are indicative of predominance of digestive serine proteinases in gut homogenate from Plodia interpunctella larvae. This serine proteinase was then used as a target to evaluate the effect of SBTI on larvae in in vivo assay. Effect of SBTI on mortality and larval mass was not observed at until 4% of concentration (w/w) in diets. Chitin, another target to insecticidal proteins, was observed by chemical method. Moreover, optic microscopy confirmed the presence of a peritrophic membrane. Established this target, in vivo effect of EvV, a chitin binding vicilin, evaluated during the larval development of P. interpunctella and was obtained a LD50 of 0,23% and WD50 of 0,27% to this protein. Mechanism of action was proposed through of the in vivo digestibility of EvV methodology. During the passage through the larval digestive tract was observed that EvV was susceptible to digestive enzymes and a reactive fragment, visualized by Western blotting, produced by digestion was recovered after dissociation of the peritrophic membrane. The bound of EvV to peritrophic membrane was confirmed by immunohystochemical assays that showed strong immunofluorescent signal of EvV-FITC binding and peritrophic membrane. These results are a indicative that vicilins could be utilized as potential insecticide to Plodia interpunctella and a control methods using EvV as bioinsecticide should be studied to reduce lost caused by storage insect pests

Adição de nanopartículas de Ti em matriz de Fe através da deposição por magnetron sputtering

Microalloyed steels constitute a specific class of steel with low amount of carbon and microalloying elements such as Vanadium (V), Niobium (Nb) and Titanium (Ti). The development and application of microalloyed steels and steels in general are limited to the handling of powders with particles of submicron or nanometer dimensions. Therefore, this work presents an alternative in order to construction of microalloyed steels utilizing the deposition by magnetron sputtering technique as a microalloying element addiction in which Ti nanoparticles are dispersed in an iron matrix. The advantage of that technique in relation to the conventional metallurgical processes is the possibility of uniformly disperse the microalloying elements in the iron matrix. It was carried out deposition of Ti onto Fe powder in high CH4, H2, Ar plasma atmosphere, with two deposition times. After the deposition, the iron powder with nanoparticles of Ti dispersed distributed, were compacted and sintered at 1120 ° C in resistive furnace. Characterization techniques utilized in the samples of powder before and after deposition of Ti were Granulometry, Scanning Electron Microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (DRX). In the case of sintered samples, it was carried out characterization by SEM and Vickers Microhardness assays. The results show which the deposition technique by magnetron sputtering is practicable in the dispersion of particles in iron matrix. The EDX microanalysis detected higher percentages of Ti when the deposition were carried out with the inert gas and when the deposition process was carried out with reactive gas. The presence of titanium in iron matrix was also evidenced by the results of X-ray diffraction peaks that showed shifts in the network matrix. Given these results it can be said that the technique of magnetron sputtering deposition is feasible in the dispersion of nanoparticles of iron matrix in Ti.

Influência das mudanças climáticas na estrutura funcional da comunidade fitoplanctônica em um reservatório da região do semiárido

The Brazilian Northeast is the most vulnerable region to climatic variability risks. For the Brazilian semi-arid is expected a reduction in the overall rates of precipitation and an increase in the number of dry days. These changes predicted by the IPCC (2007) will intensify the rainfall and droughts period that could promote the dominance of cyanobacteria, thus affecting the water quality of reservoirs, that are most used for water supply, in the semi-arid. The aim of this study was to evaluate the effects of increasing temperature combined with nutrient enrichment on the functional structure of the phytoplankton community of a mesotrophic reservoir in the semi-arid, in the worst case scenario of climate change predicted by the IPCC (2007). Two experiments were performed, one in a rainy season and another in the dry season. In the water sampled, nutrients (nitrate and orthophosphate) were added in different concentrations. The microcosms were submitted to two different temperatures, five-year average of air temperature in the reservoir (control) and 4°C above the control temperature (warming). The results of this study showed that warming and nutrient enrichment benefited mainly the functional groups of cyanobacteria. During the rainy season it was verified the increasing biomass of small functional groups of unicellular and opportunists algae such as F (colonial green algae with mucilage) and X1 (nanoplanktonic algae of eutrophic lake systems). It was also observed an increasing in total biomass, in the richness and diversity of the community. In the dry season experiment there was a greater contribution in the relative biomass of filamentous algae, with a replacement of the group S1 (non-filamentous cyanobacteria with heterocytes) for H1 (filamentous cyanobacteria with heterocytes) in nutrient- enriched treatments. Moreover, there was also loss in total biomass, species richness and diversity of the community. The effects of temperature and nutrients manipulation on phytoplankton community of reservoir Ministro João Alves provoked changes in species richness, the diversity of the community and its functional composition, being the dry period which showed the highest susceptibility to the increase in the contribution of potentially toxic cyanobacteria with heterocytes

Políticas públicas para o turismo e desenvolvimento local: reflexões a partir dos "caminhos de fé" no semi-árido potiguar

This study analyzes the event of the Feast of Our Lady of Grace, located in the municipality of Florania / RN as a tourism product, inserted in a process of transformation of a sacred place, in principle determined by religious motives, in a destination "tourist-religious". We seek to understand to what extent state intervention, with policies aimed at boosting the tourism sector as well as the interactions among key actors in the space, are able to modify and streamline the city of Florania, particularly Feast of Our Lady of Grace. The methodology also includes the review of the literature using the deductive method the application of questionnaires to the pilgrims, tourists and pilgrims totaling 150 questionnaires. Along with the economic agents of the municipality, 36 questionnaires were administered according to the model adopted by REDESIST. Complement this research interviews with key Officials of the Municipal Government and the Church. Despite the recognition by the actors of the importance of tourism to the economy of the city of Florania, encouraging the development of the sector is still lagging, some worked and policies / programs listed actually pass by the "Paths of Faith" of Florania. Concerning the Feast of Our Lady of Grace, the bottlenecks reported by researchers and economic agents are very partially affected by the policies / programs and when this occurs, the effort seems to be only reactive, resulting from the pressures experienced by the municipal government (mayor)

Uma arquitetura distribuída de hardware e software para controle de um robô móvel autônomo

In this work, we present a hardware-software architecture for controlling the autonomous mobile robot Kapeck. The hardware of the robot is composed of a set of sensors and actuators organized in a CAN bus. Two embedded computers and eigth microcontroller based boards are used in the system. One of the computers hosts the vision system, due to the significant processing needs of this kind of system. The other computer is used to coordinate and access the CAN bus and to accomplish the other activities of the robot. The microcontroller-based boards are used with the sensors and actuators. The robot has this distributed configuration in order to exhibit a good real-time behavior, where the response time and the temporal predictability of the system is important. We adopted the hybrid deliberative-reactive paradigm in the proposed architecture to conciliate the reactive behavior of the sensors-actuators net and the deliberative activities required to accomplish more complex tasks

Construção de células solares de corantes fotoexcitáveis utilizando flavonóides da capsicum frutescens, pimenta malagueta

The conversion of solar energy in electric with photo-voltaic cells has been carried through exclusively with devices of semiconducting junction. To put this situation comes moving for better in them last years, thanks to a new technology of production of known solar cells as Dye Solar Cell. This proposal aims at to develop a DSC having as dye lavonoides of the Capsicum frutescens (malagueta pepper). Front is considered to evaluate the photo-voltaic parameters varies it regions of the visible specter, as well as a good efficiency of conversion

Implementação de um modelo computacional para estudo do processo Fischer-Tropsch em reator de leito de lama

This work aims at the implementation and adaptation of a computational model for the study of the Fischer-Tropsch reaction in a slurry bed reactor from synthesis gas (CO+H2) for the selective production of hydrocarbons (CnHm), with emphasis on evaluation of the influence of operating conditions on the distribution of products formed during the reaction.The present model takes into account effects of rigorous phase equilibrium in a reactive flash drum, a detailed kinetic model able of predicting the formation of each chemical species of the reaction system, as well as control loops of the process variables for pressure and level of slurry phase. As a result, a system of Differential Algebraic Equations was solved using the computational code DASSL (Petzold, 1982). The consistent initialization for the problem was based on phase equilibrium formed by the existing components in the reactor. In addition, the index of the system was reduced to 1 by the introduction of control laws that govern the output of the reactor products. The results were compared qualitatively with experimental data collected in the Fischer-Tropsch Synthesis plant installed at Laboratório de Processamento de Gás - CTGÁS-ER-Natal/RN

Aplicação da água residuária das salinas no tratamento de efluente têxtil

The treatment of colored and alkaline effluent has been a challenge to the textile industry. An alternative to remove the colors of those effluents is applying magnesium chloride as a coagulant agent. The magnesium ion, in high pH, hydrolyzes itself, forming the magnesium hydroxide which has a large adsorptive area and positive electrostatic charges able to act as an efficient coagulant. The bittern wastewater from the salt industries has been studied as a potential font of this magnesium ion. Nowadays, this bittern wastewater is evicted into the sea, without any treatment or other use. This thesis has evaluated the potential of applying the wastewater from the salt industries in the treatment of dyeing effluent containing indigo dye and alkaline pH. All the experiments were made in jar tests simulating the chemical coagulation, flocculation and decantation steps ranging the pH and the concentration of magnesium ion. Were obtained removals between 96% and 76% for turbidity, apparent color, and true color, respectively, using 200mg/L Mg2+. The reduction of costs with acid, when were used the salt industries wastewater, comparing with Al2(SO4)3, was 62%. For the degradation of organic matter remaining in the clarified, around 900 mg/L, was applyed the advanced process of oxidation: photo-Fenton. The preliminary results showed 57% reduction in DOC. According to the results obtained, the salt industries wastewater can be applied, as coagulant, in the physical-chemical treatment of the denim dyeing wastewater, so it is not necessary a previous adjust of pH, efficiently and economically

Sistemas microemulsionados aplicados à remoção da cor de efluente têxtil

Effluent color resulting from textile dyeing processes has been one of the biggest environmental problems faced by the textile industry. In particular, reactive dyes are highly resistant to conventional wastewater treatment methods. New technologies have been contemplated, some of which have been applied in industrial treatment plants, but color removal has not been efficiently attained. Since microemulsion systems provide good results in heavy metals and proteins extraction processes, their use in dyes extraction has been suggested and investigated. In this work, a real textile wastewater from an exhaustion dyebath has been treated, which contains the following reactive dyes: Procion Yellow H-E4R (CI Reactive Yellow 84), Procion Blue H-ERD (CI Reactive Blue 160) and Procion Red H-E3B (CI Reactive Red 120), in addition to auxiliary compounds normally found in dyeing processes with reactive dyes. The dyes Remazol Blue RR and Remazol Turquoise Blue G (Reactive Blue 21) have also been examined in view of the presence of heavy metals in these molecules. The microemulsion system comprised dodecyl ammonium chloride (as a cationic surfactant), water or wastewater as aqueous phase, kerosene as oil phase, and one of the following alcohols as cosurfactant: isoamyl alcohol, n-butyl alcohol and n-octyl alcohol. The pseudo-ternary diagrams were constructed in order to define Winsor s equilibrium regions. The influence of parameters such as pH, C/S (cosurfactant/surfactant) ratio, distribution coefficient, initial dye concentration, salinity, temperature, phases relative amounts, loading capacity of the microemulsion phase and dye reextraction rate has also been investigated. An experimental planning (Scheffé Net) was used to optimize the extraction process. The removal of color and metals reached levels as high as 99%

Filmes nanométricos de FeN e ALN crescidos por sputtering e aplicações do efeito peltier

This study will show the capability of the reactive/nonreactive sputtering (dc/rf) technique at low power for the growth of nanometric thin films from magnetic materials (FeN) and widegap semiconductors (AlN), as well as the technological application of the Peltier effect using commercial modules of bismuth telluride (Bi2Te3). Of great technological interest to the high-density magnetic recording industry, the FeN system represents one of the most important magnetic achievements; however, diversity of the phases formed makes it difficult to control its magnetic properties during production of devices. We investigated the variation in these properties using ferromagnetic resonance, MOKE and atomic force microscopy (AFM), as a function of nitrogen concentration in the reactive gas mixture. Aluminum nitride, a component of widegap semiconductors and of considerable interest to the electronic and optoelectronic industry, was grown on nanometric thin film for the first time, with good structural quality by non-reactive rf sputtering of a pure AlN target at low power (≈ 50W). Another finding in this study is that a long deposition time for this material may lead to film contamination by materials adsorbed into deposition chamber walls. Energy-dispersive X-ray (EDX) analysis shows that the presence of magnetic contaminants from previous depositions results in grown AlN semiconductor films exhibiting magnetoresistance with high resistivity. The Peltier effect applied to commercially available compact refrigeration cells, which are efficient for cooling small volumes, was used to manufacture a technologically innovative refrigerated mini wine cooler, for which a patent was duly registered

Desenvolvimento e caracterização de dispositivos para reposição de filmes finos por descarga em cátodo oco

In the present work we use a plasma jet system with a hollow cathode to deposit thin TiO2 films on silicon substrates as alternative at sol-gel, PECVD, dip-coating e magnetron sputtering techniques. The cylindrical cathode, made from pure titanium, can be negatively polarized between 0 e 1200 V and supports an electrical current of up to 1 A. An Ar/O2 mixture, with a total flux of 20 sccm and an O2 percentage ranging between 0 and 30%, is passed through a cylindrical hole machined in the cathode. The plasma parameters and your influence on the properties of deposited TiO2 films and their deposition rate was studied. When discharge occurs, titanium atoms are sputtered/evaporated. They are transported by the jet and deposited on the Si substrates located on the substrate holder facing the plasma jet system at a distance ranging between10 and 50 mm from the cathode. The working pressure was 10-3 mbar and the deposition time was 10 -60 min. Deposited films were characterized by scanning electron microscopy and atomic force microscopy to check the film uniformity and morphology and by X-ray diffraction to analyze qualitatively the phases present. Also it is presented the new dispositive denominate ionizing cage, derived from the active screen plasma nitriding (ASPN), but based in hollow cathode effect, recently developed. In this process, the sample was involved in a cage, in which the cathodic potential was applied. The samples were placed on an insulator substrate holder, remaining in a floating potential, and then it was treated in reactive plasma in hollow cathode regime. Moreover, the edge effect was completely eliminated, since the plasma was formed on the cage and not directly onto the samples and uniformity layer was getting in all sampl

Efeito in vitro da terapia fotodinâmica sobre bactérias orais em suspensão e na formação de biofilme : ensaio com azul de metileno e toluidina ativados por luz halógena

Photodynamic therapy (PDT) has been proposed as an alternative method for the treatment of biofilm-dependent oral diseases like dental caries. This therapy consists of simultaneous action of a visible light (L) and a photosensitizer (FS) in the presence of oxygen, which leads to production of different reactive oxygen species that can interact with the bacterial cell components, and promote cell death. This study aims to evaluate the antimicrobial action of PDT on oral bacteria in suspension, as well as the formation of mono and multi-species biofilms, in vitro, from a standard strain of Streptococcus mutans (ATCC 25175) and saliva samples, respectively. The dye methylene blue (MB) and toluidine blue (TB) were used at a concentration of 100 mg/ L and activated by halogen light (600 to 750 nm) from a modified hand held photopolymerizer (Ultralux ®, Dabi Atlante, Ribeirão Preto , São Paulo, Brazil.). Planktonic cultures were prepared and submitted to different experimental conditions: 1. PDT using TB 2. PDT using MB, 3. L+ FS- , 4. TB + L - ; 5. MB+ L-; 6. L- FS- (negative control) and 7. administration of 0.12% chlorhexidine digluconate (positive control) (Periogard ®, Colgate-Palmolive Company, New York, USA). The immediate and mediated action of PDT on bacterial suspensions, as well as its effect on biofilm formation were observed from the number of colony-forming units per milliliter (CFU/mL) and measures optical density (OD). The data were statistically analyzed using the Kruskal-Wallis and Mann-Whitney test for the significance level of 5%. According to the results, the PDT showed no antibacterial action on suspensions of S. mutans, regardless of the dye used. PDT with MB activated by halogen light was able to reduce 86.6% CFU/mL multi-species planktonic cultures, however, this reduction was not significant (p > 0.05). PDT showed antibacterial effect, mediate on multi-species planktonic cultures with TB (p < 0.001) and MB (p < 0.001), activated by halogen light. PDT was able to prevent the formation of multispecies biofilm, through the activation of TB by halogen light (p = 0.01). We conclude that activation of the dye toluidine blue and methylene blue, by halogen light (PDT) showed antimicrobial activity, compared to multi-species planktonic cultures prepared from saliva samples

Comprovação da real comunicação entre o endodonto e o periodonto através do canal cavo inter-radicular e sua prevalência em molares inferiores humanos

The neurovascular system of the pulp and of the periodontium is interconnected and among the possible intercommunications between these two tissues, there is the cavo inter-radicular canal. It is a small canal that goes through any inter-radicular dentine and arises in the furca region of the multi-radicular teeth. Its predominance has been studied in the literature, by several methodologies, with divergent results. The objective of this work was to establish, in vitro, the predominance of the cavo inter-radicular canal, in human lower molars, through the diaphanization technique and dye leakage. For this research, 140 teeth (100 first and second 40 lower molars) were selected, extracted due to different reasons, belonging to a teeth bank of the Endodontics discipline of the Dentistry College at Federal University of Rio Grande do Norte. The teeth were preserved in formol until the moment of use and immersed in physiological solution. Had the endodontic access fulfilled and the whole external surface, except for the furcation, sealed with two layers of nail enamel. The cleaning of the pulpar chamber floor was carried out with sodium hypochlorite solution 5%, being this solution renewed every 5 minutes, during 1 hour. The teeth were immersed in Indian dye and, after drying of the dye, they had their crowns split up in the amelo-cemental junction. Then, they were examined in a stereomicroscope, where marks of the coloring were observed in the furcation and on the pulpar floor. After this recording, the sample was diaphanized and with the transparent teeth, it was possible to observe in the stereomicroscope, the true inter-radicular canals. As a result of this experiment, the presence of these canals was observed in 13 % of the first and 7, 5 % of the second evaluated molars. The study showed that both the presence of the cavo inter-radicular canal is real and the diaphanization and dye leakage is an efficient method for this type of research