Desenvolvimento e validação de testes de fluxo lateral para a detecção de cultivares geneticamente modificados e de aflatoxinas em produtos agrícolas

The expansion of cultivated areas with genetically modified crops (GM) is a worldwide phenomenon, stimulating regulatory authorities to implement strict procedures to monitor and verify the presence of GM varieties in agricultural crops. With the constant growing of plant cultivating areas all over the world, consumption of aflatoxin-contaminated food also increased. Aflatoxins correspond to a class of highly toxic contaminants found in agricultural products that can have harmful effects on human and animal health. Therefore, the safety and quality evaluation of agricultural products are important issues for consumers. Lateral flow tests (strip tests) is a promising method for the detection both proteins expressed in GM crops and aflatoxins-contaminated food samples. The advantages of this technique include its simplicity, rapidity and cost-effective when compared to the conventional methods. In this study, two novel and sensitive strip tests assay were developed for the identification of: (i) Cry1Ac and Cry8Ka5 proteins expressed in GM cotton crops and; (ii) aflatoxins from agricultural products. The first strip test was developed using a sandwhich format, while the second one was developed using a competitive format. Gold colloidal nanoparticles were used as detector reagent when coated with monoclonal antibodies. An anti-species specific antibody was sprayed at the nitrocellulose membrane to be used as a control line. To validate the first strip test, GM (Bollgard I® e Planta 50- EMBRAPA) and non-GM cotton leaf (Cooker 312) were used. The results showed that the strip containing antibodies for the identification of Cry1Ac and Cry8Ka5 proteins was capable of correctly distinguishing between GM samples (positive result) and non-GM samples (negative result), in a high sensitivity manner. To validate the second strip test, artificially contaminated soybean with Aspergillus flavus (aflatoxin-producing fungus) was employed. Food samples, such as milk and soybean, were also evaluated for the presence of aflatoxins. The strip test was capable to distinguish between samples with and without aflatoxins samples, at a sensitivity concentration of 0,5 μg/Kg. Therefore, these results suggest that the strip tests developed in this study can be a potential tool as a rapid and cost-effective method for detection of insect resistant GM crops expressing Cry1Ac and Cry8Ka5 and aflatoxins from food samples.

Desenvolvimento e validação de testes de fluxo lateral para a detecção de cultivares geneticamente modificados e de aflatoxinas em produtos agrícolas

The expansion of cultivated areas with genetically modified crops (GM) is a worldwide phenomenon, stimulating regulatory authorities to implement strict procedures to monitor and verify the presence of GM varieties in agricultural crops. With the constant growing of plant cultivating areas all over the world, consumption of aflatoxin-contaminated food also increased. Aflatoxins correspond to a class of highly toxic contaminants found in agricultural products that can have harmful effects on human and animal health. Therefore, the safety and quality evaluation of agricultural products are important issues for consumers. Lateral flow tests (strip tests) is a promising method for the detection both proteins expressed in GM crops and aflatoxins-contaminated food samples. The advantages of this technique include its simplicity, rapidity and cost-effective when compared to the conventional methods. In this study, two novel and sensitive strip tests assay were developed for the identification of: (i) Cry1Ac and Cry8Ka5 proteins expressed in GM cotton crops and; (ii) aflatoxins from agricultural products. The first strip test was developed using a sandwhich format, while the second one was developed using a competitive format. Gold colloidal nanoparticles were used as detector reagent when coated with monoclonal antibodies. An anti-species specific antibody was sprayed at the nitrocellulose membrane to be used as a control line. To validate the first strip test, GM (Bollgard I® e Planta 50- EMBRAPA) and non-GM cotton leaf (Cooker 312) were used. The results showed that the strip containing antibodies for the identification of Cry1Ac and Cry8Ka5 proteins was capable of correctly distinguishing between GM samples (positive result) and non-GM samples (negative result), in a high sensitivity manner. To validate the second strip test, artificially contaminated soybean with Aspergillus flavus (aflatoxin-producing fungus) was employed. Food samples, such as milk and soybean, were also evaluated for the presence of aflatoxins. The strip test was capable to distinguish between samples with and without aflatoxins samples, at a sensitivity concentration of 0,5 μg/Kg. Therefore, these results suggest that the strip tests developed in this study can be a potential tool as a rapid and cost-effective method for detection of insect resistant GM crops expressing Cry1Ac and Cry8Ka5 and aflatoxins from food samples.

Efeitos da terapia fotodinâmica com aluminio – cloro ftalocianina sobre a peroxidação lipídica e produtos antioxidantes em tecidos inflamados animais

Photodynamic therapy (PDT) consists of a non-toxic photosensitizing agent (FS) administration followed by a laser source resulting in a sequence of photochemical and photobiological processes that generate reactive oxygen species (ROS) that damaging cells. The present work evaluated the effects of PDT nanoemulsion-aluminum chloride phthalocyanine (AlClFc) mediated on malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels, which represent indicators involved in oxidative stress and antioxidant defenses. For this purpose, this study used 120 female rats of the Rattus norvegicus species, Wistar race, divided into 5 groups: Healthy (H), with periodontal disease (PD), with periodontal disease and treatment with FS (F), with periodontal disease and treatment with the laser (L); and periodontal disease and treatment with PDT (FL). An experimental model for represent periodontal disease (PD) was induced by ligature (split-mouth). Seven days later the induction of PD, the treatments were instituted according to the groups. In the group treated with PDT was applied 40μl FS (5μM) followed by laser irradiation diode InGaAlP (660nm, 100J / cm2). The rats were sacrificed on the 7th and 28th day after treatment and tissue specimens were removed and subjected to histological, immunohistochemical methods and enzymatic colorimetric measurements with detection by UV / VIS spectroscopy. Inflammatory changes, connective tissue disorganization and alveolar bone loss were displaying in groups with PD induced. The enzyme dosages showed that MDA levels were higher in PD induced groups, with no statistically significant differences (p> 0.05). High levels of GSH were found in groups L (p = 0.028) and FL (p = 0.028) compared with PD group, with statistically significant differences. Immunohistochemistry for SOD showed higher immunostaining in L and FL groups, compared to the PD group without statistically significant differences (p> 0.05). GPx showed lower immunoreactivity in the DP group when compared to the other groups and statistically significant differences were observed between the DPxL groups (p <0.05). TFD administered in this experiment did not induce elevation of MDA levels significantly increased the GSH levels and showed intense immunostaining pada SOD and GPx, showing that this therapy does not accentuated lipid peroxidation, however, it was able to induce effects on the antioxidant defenses processes. The LBI therapy appeared to show photomodulatory promoting effects reduction of the MDA levels, increasing GSH levels and with intense immunostaining for SOD and GPx, demonstrating that laser therapy induced antioxidant effects.

Relações interorganizacionais e confiança no setor da carcinicultura: um estudo de caso na camanor produtos marinhos

This study investigated how the types of confidence based on competence and good will act in the formation and maintenance of cooperation relationships between the Camanor and its partners (Aquatec, Purina, Caçuá, Uvifrios and Malta / Cleyton). It used organizational approaches on networks based primarily on studies of Powell (1987, 1990), Das and Teng (2000, 2001), Child (2001) and Contractor and Lorange (2004) which have described the advantages that cooperative relationships can provide, as well as their limits as alternative governance structures. Confidence has been considered an important factor affecting the actions and development of organizations involved in networks or in strategic alliances (ZAHEER; HARRIS, 2006) and is the most appropriate control mechanism in these situations (SYDOW, 1998). Confidence is seen from two different approaches: the economic and the sociological (ZAHEER; HARRIS, 2006). To facilitate the understanding of confidence some typologies have been created, as proposed by Barney and Hansen (1994), Lane (1998), Das and Teng (2000), Child (2001) and Wever, Martens and Vandenbempt (2005). This study made use of the case study as proposition of Yin (2005). Semi-structured interviews were held with pre-determined routes, in a single stage performed in early 2008. The research subjects were owners and / or responsible for Camanor and its business partners (Aquatec, Purina, Caçuá, Uvifrios and Malta / Cleyton). Also secondary data were collected in several sites related to the industry and enterprises studied, in addition to data collected by previous studies conducted by CARCINEREDES (2006). The primary data were analyzed using the analysing technique of the content proposed by Bardin (1994). Regarding the secondary data, they were qualitatively analyzed according to documentary analysis technique (BARDIN, 1994). Thus, through the data collected, could be concluded that although there is confidence based on good faith in relationships(UZZI, 1998; OF; TENG, 2001), their presence does not determine the formation and / or maintenance of a partnership, serves only in order to facilitate the relationship, making them more flexible. The confidence based on competence (DAS; TENG, 2001) influenced the formation and maintenance of relations studied. Because whether or not to form a relationship with another organization it is used the perception of the partner acts, namely the reputation (image) as decision basis. And it is through the verification of the performance of the partner activities that will determine the continuation of the partnership

Influência dos intermediários de distribuição de produtos turísticos no processo de decisão do meio de hospedagem pelo consumidor

This study examines the complex hotel buyer decision process in front of the tourism distribution channels. Its objective is to describe the influence level of the tourism marketing intermediaries, mainly the travel agents and tour operators, over the hotel decision process by the buyer-tourist. The data collection process was done trough a survey with three hundred brazilian tourists hosted in nineteen hotels of Natal, capital of Rio Grande do Norte, Brazil. The data analysis was done using some multivariate statistic techniques as correlation analysis, multiple regression analysis, factor analysis and multiple discriminant analysis. The research characterizes the hotel services consumers profile and his trip, and identifying the distribution channels used by them. Furthermore, the research verifies the intermediaries influence exercised over hotel buyer decision process, looking for identify causality relations between the influence level and the buyer profile. Verifies that information about hotels available on internet reduces the probability that this influence can be practiced; however it was possible identifying those consumers considers this information complementary and non-substitutes than the information from intermediaries. The characteristics of the data do not allow indentifying the factors that constraint the intermediaries influence neither identifying discriminant functions of the specific distribution channel choice by consumers. The study concludes that consumers don t agree in have been influenced by intermediaries or don t know if they have, still considering important to consult them and internet doesn t substitute their function as information source

Gestão do marketing de relacionamento: um estudo em empresas hoteleiras de Natal - RN

The present study it analyzes the Management of the Marketing of strategy Relationship as distinguishing for the host s companies of the city of Natal - RN. To carry through this analysis interviews with managers had been carried through, as well as the direct comment of processes, documents, actions and strategies developed for the hotels, with intention to know the level of perception and valuation of the relationship with customers, to verify resources and technologies used in the Management of the Relationship Marketing, identification, segmentation and differentiation of customers, personalization of products and services, and results of the emphasis in the relationship with customers for the host s companies. The research can be classified as exploratory - descriptive, and its universe is limited to the city of Natal, having enclosed hotels that have carried through tourist activity in 2005 and 2006. Still on the criteria of election of the sample, the study it investigated host s companies who if fit in the category superior luxury, or either, five stars, pertaining the national nets and international. How much to the treatment and analysis of the data the was made to leave of the theoretical support of the authors who work the thematic one and of the analysis of the interviews with managers, documents and processes observed for the researcher in the studied hotels. The research sample that the interviewed ones understand the importance to work the Management of the Marketing of Relationship in the host s companies me intention to get sustainable competitive advantage. One still evidenced that the searched hotels make use of strategies and instruments of Management of the Marketing of Relationship, however without an ample theoretical knowledge and yes only as base in the experience of the managers and spread processes already, generating one moment competitive advantage and not relationships of long duration

Efeito da velocidade de aquecimento nas propriedades de produtos da cerâmica estrutural

Heating rate is one of the main variables that determine a fire cycle. In industrial processes that use high temperatures, greater fire great can reduce the cost of production and increase productivity. The use of faster and more efficient fire cycles has been little investigated by the structural ceramic industry in Brazil. However, one of the possibilities that aims at modernizing the sector is the use of roller kilns and the inclusion of natural gas as fuel. Thus, the purpose of this study is to investigate the effect of heating rate on the technological properties of structural ceramic products. Clay raw materials from the main ceramic industries in the state of Rio Grande do Norte were characterized. Some of the raw materials characterized were formulated to obtain the best physical and mechanical properties. Next, raw materials and formulations were selected to study the influence of heating rate on the final properties of the ceramic materials. The samples were shaped by pressing and extrusion and submitted to rates of 1 °C/min, 10 °C/min and 20 °C/min, with final temperatures of 850 °C, 950 °C and 1050 °C. Discontinuous cycles with rates of 10 °C/min or 15 °C/min up to 600 °C and a rate of 20 °C/min up to final temperature were also investigated. Technological properties were determined for all the samples and microstructural analysis was carried out under a number of fire conditions. Results indicate that faster and more efficient fire cycles than those currently in practice could be used, limiting only some clay doughs to certain fire conditions. The best results were obtained for the samples submitted to slow cycles up to 600 °C and fast fire sinterization up to 950 °C. This paper presents for the first time the use of a fast fire rate for raw materials and clay formulations and seeks to determine ideal dough and processing conditions for using shorter fire times, thus enabling the use of roller kilns and natural gas in structural ceramic industries

Avaliação de produtos naturais no controle de biofilmes formados em sistema dinâmico

The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective