998 resultados para SDS (lauril sulfato de sódio)


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The coatings mortars are essential elements of building structures because they execute an important role in protecting walls and are particularly exposed to aggressive action responsible for its degradation over time. The importance of wall coverings has been the subject of discussion and analysis in the conservation and rehabilitation of old buildings. Are sometimes removed and replaced with inappropriate solutions of constructive point of view or architecture. The most commonly used coatings on walls of old buildings is based on traditional hydraulic lime mortars. The present study aims at the formulation of new lime- based mortars and aerial fine aggregate, in order to contribute to a better field of conservation and restoration mortar coating of old buildings. Residue was used for polishing porcelain as fine aggregate, replacing the aggregate (sand), in percentages 05-30% by mass. We conducted a thorough evaluation of the mortar properties in fresh and hardened state by comparing the performance of the same with a reference mortar. The residue used was characterized as the density, bulk density, and particle size laser, scanning electron microscopy, X-ray diffraction and X-ray fluorescence. Formulations were produced 7, 6 with residue and one commonly used formulation, which served as a reference. In the formulations of lime mortars air (hydrated lime powder CH-I) has been adopted a stroke volume (1:3) with constant binder, was varied and the water / binder and aggregate and waste. For evaluation of mortars fresh, proceeded to consistency analysis, specific gravity, water retention and air content embedded. In the hardened state assays were performed in specific gravity, water retention, modulus of elasticity, tensile strength in bending, compressive strength, water absorption by capillary action, adhesion, tensile strength, resistance to shrinkage and salts by of crystallization trials with resources chloride solution, nitrate and sulfate all sodium in prismatic at 90 days of age, in addition to the micro structural analysis of mortars. Based on the results we can see that the mortar formulated with 10% content of waste and the reference free retraction feature more stable closer to neutrality. The composition of 10% was obtained better performance against the action of the salt crystallization. The mortar with 15% residue obtained better density, lower air content embedded and high capacity for water retention developing good workability. The replacement of 20% of waste generates a satisfactory utilization of resistance to compression, flexion and traction grip the base. And, finally, it can be seen that the mortar with 10, 15 and 20% residual show, in principle, good suitability as coatings, thus enabling a final result consistent with durability, workability and aesthetics developing therefore a material with better performance to repair or replace existing mortars in old buildings

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The development of activities in the oil and gas sector has been promoting the search for materials more adequate to oilwell cementing operation. In the state of Rio Grande do Norte, the cement sheath integrity tend to fail during steam injection operation which is necessary to increase oil recovery in reservoir with heavy oil. Geopolymer is a material that can be used as alternative cement. It has been used in manufacturing of fireproof compounds, construction of structures and for controlling of toxic or radioactive waste. Latex is widely used in Portland cement slurries and its characteristic is the increase of compressive strength of cement slurries. Sodium Tetraborate is used in dental cement as a retarder. The addition of this additive aim to improve the geopolymeric slurries properties for oilwell cementing operation. The slurries studied are constituted of metakaolinite, potassium silicate, potassium hydroxide, non-ionic latex and sodium tetraborate. The properties evaluated were: viscosity, compressive strength, thickening time, density, fluid loss control, at ambient temperature (27 ºC) and at cement specification temperature. The tests were carried out in accordance to the practical recommendations of the norm API RP 10B. The slurries with sodium tetraborate did not change either their rheological properties or their mechanical properties or their density in relation the slurry with no additive. The increase of the concentration of sodium tetraborate increased the water loss at both temperatures studied. The best result obtained with the addition of sodium tetraborate was thickening time, which was tripled. The addition of latex in the slurries studied diminished their rheological properties and their density, however, at ambient temperature, it increased their compressive strength and it functioned as an accelerator. The increase of latex concentration increased the presence of water and then diminished the density of the slurries and increased the water loss. From the results obtained, it was concluded that sodium tetraborate and non-ionic latex are promising additives for geopolymer slurries to be used in oilwell cementing operation

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The human activities responsible for the ambient degradation in the modern world are diverse. The industrial activities are preponderant in the question of the impact consequences for brazilian ecosystems. Amongst the human activities, the petroliferous industry in operation in Potiguar Petroliferous Basin (PPB) displays the constant risk of ambient impacts in the integrant cities, not only for the human populations and the environment, but also it reaches the native microorganisms of Caatinga ground and in the mangrove sediment. Not hindering, the elaboration of strategies of bioremediation for impacted areas pass through the knowledge of microbiota and its relations with the environment. Moreover, in the microorganism groups associated to oil, are emphasized the sulfate-reducing prokaryotes (SRP) that, in its anaerobic metabolism, these organisms participate of the sulfate reduction, discharging H2S, causing ambient risks and causing the corrosion of surfaces, as pipelines and tanks, resulting in damages for the industry. Some ancestries of PRS integrate the Archaea domain, group of microorganisms whose sequenced genomes present predominance of extremophilic adaptations, including surrounding with oil presence. This work has two correlated objectives: i) the detection and monitoring of the gene dsrB, gift in sulfate-reducing prokaryotes, through DGGE analysis in samples of mDNA of a mangrove sediment and semiarid soil, both in the BPP; ii) to relate genomic characteristics to the ecological aspects of Archaea through in silico studies, standing out the importance to the oil and gas industry. The results of the first work suggest that the petrodegraders communities of SRP persist after the contamination with oil in mangrove sediment and in semiarid soil. Comparing the populations of both sites, it reveals that there are variations in the size and composition during one year of experiments. In the second work, functional and structural factors are the probable cause to the pressure in maintenance of the conservation of the sequences in the multiple copies of the 16S rDNA gene. Is verified also the discrepancy established between total content GC and content GC of the same gene. Such results relating ribosomal genes and the ambient factors are important for metagenomic evaluations using PCR-DGGE. The knowledge of microbiota associated to the oil can contribute for a better destination of resources by the petroliferous industry and the development of bioremediation strategies. Likewise, search to lead to the best agreement of the performance of native microbiota in biogeochemical cycles in Potiguar Petroliferous Basin ecosystem

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-D-glucosidase (EC 3.2.1.21) is one of the most interesting glycosidases, especially for hydrolysis cellobiose releasing glucose, is last step degradation of cellulose. This function makes the -D-glucosidase is of great interest as a versatile industrial biocatalyst, being critical to various bio-treatment / biorefinery processes, such as bioethanol production. Hen in the report, a -D-glucosidase was extracts from protein extracted of the invertebrate marine Artemia franciscana was purified and characterized with a combination of precipitation with ammonium sulfate (0 - 30%, 30 to 50%, 50 to 80%), the fraction saturated in the range of 30 to 50% (called F-II) was applied in a molecular exclusion chromatography, in Sephacryl S-200, the fractions corresponding to the first peak of activity of -D-glucosidase were gathered and applied in a chromatography of ion exchange in Mono Q; the third peak this protein obtained chromatography, which coincides with the peak of activity of -D-glucosidase was held and applied in a gel filtration chromatography Superose 12 where the first peak protein, which has activity of -D-glucosidase was rechromatography on Superose 12. This enzyme is probably multimerica, consisting of three subunit molecular mass of 52.7 kDa (determined by SDS-PAGE) with native molecular mass of 157 kDa (determined by gel filtration chromatography on Superose 12 under the system FPLC). The enzyme was purified 44.09 times with a recovery of 1.01%. Using up p-nitrophenyl-β-D-glucopiranoside as substrate obtained a Km apparent of 0.229 mM and a Vmax of 1.109 mM.60min-1.mL-1mM. The optimum pH and optimum temperature of catalysis of the synthetic substrate were 5.0 and 45 °C, respectively. The activity of the -D-glucosidase was strongly, inhibited by silver nitrate and N- etylmaleimide, this inhibition indicates the involvement of radical sulfidrila the hydrolysis of synthetic substrate. The -D-glucosidase of Artemia franciscana presented degradativa action on celobiose, lactose and on the synthetic substrate -nitrophenyl-β-D-glucopiranoside indicating potential use of this enzyme in the industry mainly for the production of bioethanol (production of alcohol from the participating cellulose), and production hydrolysate milk (devoid of milk lactose)

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O objectivo deste trabalho consistiu em definir, com base na evidência científica mais recente sobre Acidentes com hipoclorito de sódio, diferentes protocolos para a prevenção e tratamento dos acidentes causados no âmbito da endodontia. O Hipoclorito de Sódio é o irrigante frequentemente mais utilizado durante o Tratamento Endodôntico, devido às suas excelentes propriedades, capacidade de dissolver tecidos e capacidade bactericida. Há diversos factores que podem influenciar o modo de atuação do NaOCl, tais como: a concentração, a temperatura, o pH, o tempo/volume de irrigação, a agitação do irrigante, os métodos de introdução do irrigante, a conicidade apical e a profundidade de colocação da agulha. A pesquisa bibliográfica deste trabalho foi realizada nas bibliotecas da Universidade Fernando Pessoa e Faculdade de Medicina Dentária da Universidade do Porto e nos motores de internet Pubmed, Science Direct, Scielo e B-On, entre Junho de 2016 a Outubro de 2016. As palavras utilizadas para a pesquisa foram as seguintes: “desinfection endodontics”, “endodontics”, “endodontic treatment”, “sodium hypochlorite”, “irrigants endodontics”, “sodium hypochlorite accidents”, “irrigation methods”, “root canal irrigant”, “management NaOCL accidents”.

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O objetivo deste trabalho foi avaliar o efeito do sal (NaCl) sobre as respostas fisiológicas e controle de helmintos monogenóides em tambaqui (Colossoma macropomum). Para isso, juvenis de tambaqui (42,38 ± 0,47 g; 13,90 ± 0,06 cm) foram transferidos para tanques de 350L e aclimatados por um período de 24 horas. Os ensaios foram conduzidos utilizando as concentrações de 0, 2, 4, 6 e 8 g de sal comum L-1 de água, nos tempos de exposição de 30, 60 e 120 minutos, com três repetições por tratamento. A tolerância dos tambaquis ao sal e a eficácia deste sobre os helmintos monogenóides foi avaliada mediante análise dos indicadores fisiológicos (glicose, cloretos, sódio e potássio plasmático) e parasitológicos (número total de parasitas e prevalência). Tambaquis expostos a 4 g NaCl L-1 por 120 minutos, 6 e 8 g NaCl L-1 por 60 e 120 minutos apresentaram maior elevação da glicose plasmática e na concentração de 8 g NaCl L-1 por 120 minutos maiores níveis de cloreto plasmático. A prevalência de monogenóides nas brânquias foi de 100% e todas as concentrações de sal avaliadas neste estudo não foram eficazes na redução dos helmintos monogenóides em tambaqui.

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Este material compõe o Curso de Especialização em Nefrologia Multidisciplinar (Módulo 7, Unidade 3), produzido pela UNA-SUS/UFMA. Trata-se de um recurso educacional interativo que apresenta algumas recomendações para a redução do sódio na dieta, como estratégia de prevenção da Doença Renal Crônica.

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A alimentação e a nutrição constituem requisitos básicos para a promoção e a proteção da saúde. O consumo excessivo de sódio e gordura saturada está relacionado a diversas patologias, entre elas, hipertensão arterial, obesidade e hipercolesterolemia. A redução de o alto consumo de gorduras saturadas e sódio da dieta das populações e comunidades deve ser uma das prioridades da Atenção Básica de Saúde. Este trabalho teve como objetivo elaborar uma proposta de intervenção para o enfrentamento de um problema, considerado prioritário da equipe de saúde da família Capivara: o alto consumo de gorduras saturadas e sódio pelos usuários atendidos na unidade. Para a construção desta proposta de intervenção realizou-se um levantamento bibliográfico sobre o tema junto às bases de dados informatizadas da Biblioteca Virtual em Saúde (BVS) e o diagnóstico da instituição, para conhecer os fatores que favoreciam o alto consumo de gorduras saturadas e sódio na dieta da comunidade rural de Capivara. Com base nas informações adquiridas foi elaborada uma proposta de intervenção, visando sistematizar o atendimento à comunidade com ações voltadas para promoção e prevenção de agravos à saúde dos pacientes. Espera-se com este trabalho uma mudança progressiva no estilo de vida da comunidade e uma adesão da mesma a hábitos nutricionais saudáveis, reduzindo, assim, a aparição de fatores de risco e doenças crônicas não transmissíveis na área de abrangência de atendimento desta equipe

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Introdução: Atualmente, a deficiência de ferro com consequente anemia é considerado um grave problema de saúde pública no Brasil devido sua prevalência e suas implicações direta no desenvolvimento das crianças com baixo rendimento escolar e baixa produtividade quando adultos. Objetivo: Realizar uma intervenção para melhorar a adesão ao uso de sulfato ferroso profilático seguindo recomendações do Ministério da Saúde em uma população abrangente do Centro de Saúde Padre Libério, em Pará de Minas, Minas Gerais. Metodologia: Utilizando-se do método de estimativa rápida através de uma observação ativa, os profissionais do Centro de Saúde Padre Libério (CSPL) do município de Pará de Minas detectaram que poucas crianças estão em uso de sulfato ferroso profilático na idade preconizada pelo Ministério da Saúde. Resultados: Após um diagnóstico situacional quantitativo foram estabelecidos diferentes ações de intervenção para melhorar a adesão ao uso de sulfato ferroso profilático seguindo recomendações do Ministério da Saúde, em que se destacam: atividades teóricas educativas, busca ativa das crianças que não faziam uso do sulfato ferroso seguido de sua prescrição, maior controle das puericulturas. Considerações finais: Considerando a relevância da anemia por deficiência de ferro o uso de sulfato ferroso profilático se torna uma ferramenta fundamental para combatê-lo.

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The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

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It is well known that long term use of shampoo causes damage to human hair. Although the Lowry method has been widely used to quantify hair damage, it is unsuitable to determine this in the presence of some surfactants and there is no other method proposed in literature. In this work, a different method is used to investigate and compare the hair damage induced by four types of surfactants (including three commercial-grade surfactants) and water. Hair samples were immersed in aqueous solution of surfactants under conditions that resemble a shower (38 °C, constant shaking). These solutions become colored with time of contact with hair and its UV-vis spectra were recorded. For comparison, the amount of extracted proteins from hair by sodium dodecyl sulfate (SDS) and by water were estimated by the Lowry method. Additionally, non-pigmented vs. pigmented hair and also sepia melanin were used to understand the washing solution color and their spectra. The results presented herein show that hair degradation is mostly caused by the extraction of proteins, cuticle fragments and melanin granules from hair fiber. It was found that the intensity of solution color varies with the charge density of the surfactants. Furthermore, the intensity of solution color can be correlated to the amount of proteins quantified by the Lowry method as well as to the degree of hair damage. UV-vis spectrum of hair washing solutions is a simple and straightforward method to quantify and compare hair damages induced by different commercial surfactants.

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Background: Ruthenium (Ru) tetraamines are being increasingly used as nitric oxide (NO) carriers. In this context, pharmacological studies have become highly relevant to better understand the mechanism of action involved. Objective: To evaluate the vascular response of the tetraamines trans-[RuII(NH3)4(Py)(NO)]3+, trans-[RuII(Cl)(NO) (cyclan)](PF6)2, and trans-[RuII(NH3)4(4-acPy)(NO)]3+. Methods: Aortic rings were contracted with noradrenaline (10-6 M). After voltage stabilization, a single concentration (10-6 M) of the compounds was added to the assay medium. The responses were recorded during 120 min. Vascular integrity was assessed functionally using acetylcholine at 10-6 M and sodium nitroprusside at 10-6 M as well as by histological examination. Results: Histological analysis confirmed the presence or absence of endothelial cells in those tissues. All tetraamine complexes altered the contractile response induced by norepinephrine, resulting in increased tone followed by relaxation. In rings with endothelium, the inhibition of endothelial NO caused a reduction of the contractile effect caused by pyridine NO. No significant responses were observed in rings with endothelium after treatment with cyclan NO. In contrast, in rings without endothelium, the inhibition of guanylate cyclase significantly reduced the contractile response caused by the pyridine NO and cyclan NO complexes, and both complexes caused a relaxing effect. Conclusion: The results indicate that the vascular effect of the evaluated complexes involved a decrease in the vascular tone induced by norepinephrine (10-6 M) at the end of the incubation period in aortic rings with and without endothelium, indicating the slow release of NO from these complexes and suggesting that the ligands promoted chemical stability to the molecule. Moreover, we demonstrated that the association of Ru with NO is more stable when the ligands pyridine and cyclan are used in the formulation of the compound.Fundamento: As tetra-aminas de rutênio cada vez mais se destacam como carreadoras da molécula de óxido nítrico. Desse modo, estudos farmacológicos tornam-se altamente relevantes, afim de melhor compreender o mecanismo de ação envolvido. Objetivo: Avaliar a resposta vascular das tetra-aminas trans-[RuII(NH3)4(Py)(NO)]3+, trans-[RuII(Cl)(NO)(Cyclan)](PF6)2 e trans-[RuII(NH3)4(4-acPy)(NO)]3+. Métodos: Anéis de aorta foram pré-contraídos com noradrenalina (10-6M). Após estabilização da tensão, concentração única (10-6M) dos compostos foi adicionada ao banho de incubação. As respostas foram registradas ao longo de 120 minutos. A integridade vascular foi avaliada funcionalmente (acetilcolina 10-6M; nitroprussiato de sódio 10-6M) e histologicamente Resultados: A análise histológica confirmou a presença ou não de células endoteliais nos tecidos analisados. Todos os complexos alteraram a resposta contrátil induzida pela noradrenalina, resultando em aumento de tônus seguido de efeito relaxante. Em anéis com endotélio, a inibição do óxido nítrico endotelial causou redução do efeito contrátil da piridina óxido nítrico. Não foram observadas respostas significativas em anéis com endotélio referente ao composto cyclan óxido nítrico. Por outro lado, em anéis sem endotélio, a inibição da guanilato ciclase reduziu significativamente a resposta contrátil dos complexos piridina óxido nítrico e cyclan óxido nítrico, levando ambos os compostos a um efeito relaxante. Conclusão: Os resultados obtidos demonstram que o efeito vascular dos complexos avaliados apresentaram diminuição no tônus vascular induzido pela noradrenalina (10-6M) ao final do tempo de incubação, em anéis com e sem endotélio, indicando liberação lenta da molécula de óxido nítrico do composto estudado e sugerindo que os ligantes causaram estabilidade química à molécula. Demonstramos que a ligação rutênio óxido nítrico é mais estável quando utilizamos os ligantes piridina e cyclan para a formulação do composto.

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Background/Aims. Studies on 46,XY partial gonadal dysgenesis (PGD) have focused on molecular, gonadal, genital, and hormone features; little is known about follow-up. Our aim was to analyze long-term outcomes of PGD. Methods. Retrospective longitudinal study conducted at a reference service in Brazil. Ten patients were first evaluated in the 1990s and followed up until the 2010s; follow-up ranged from 13.5 to 19.7 years. All were reared as males and had at least one scrotal testis; two bore NR5A1 mutations. Main outcomes were: associated conditions, pubertal development, and growth. Results. All patients had normal motor development but three presented cognitive impairment; five had various associated conditions. At the end of the prepubertal period, FSH was high or high-normal in 3/6 patients; LH was normal in all. At the last evaluation, FSH was high or high-normal in 8/10; LH was high or high-normal in 5/10; testosterone was decreased in one. Final height in nine cases ranged from -1.57 to 0.80 SDS. All had spontaneous puberty; only one needed androgen therapy. Conclusions. There is good prognosis for growth and spontaneous pubertal development but not for fertility. Though additional studies are required, screening for learning disabilities is advisable.

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BACKGROUND: The model for end-stage liver disease (MELD) was developed to predict short-term mortality in patients with cirrhosis. There are few reports studying the correlation between MELD and long-term posttransplantation survival. AIM: To assess the value of pretransplant MELD in the prediction of posttransplant survival. METHODS: The adult patients (age >18 years) who underwent liver transplantation were examined in a retrospective longitudinal cohort of patients, through the prospective data base. We excluded acute liver failure, retransplantation and reduced or split-livers. The liver donors were evaluated according to: age, sex, weight, creatinine, bilirubin, sodium, aspartate aminotransferase, personal antecedents, brain death cause, steatosis, expanded criteria donor number and index donor risk. The recipients' data were: sex, age, weight, chronic hepatic disease, Child-Turcotte-Pugh points, pretransplant and initial MELD score, pretransplant creatinine clearance, sodium, cold and warm ischemia times, hospital length of stay, blood requirements, and alanine aminotransferase (ALT >1,000 UI/L = liver dysfunction). The Kaplan-Meier method with the log-rank test was used for the univariable analyses of posttransplant patient survival. For the multivariable analyses the Cox proportional hazard regression method with the stepwise procedure was used with stratifying sodium and MELD as variables. ROC curve was used to define area under the curve for MELD and Child-Turcotte-Pugh. RESULTS: A total of 232 patients with 10 years follow up were available. The MELD cutoff was 20 and Child-Turcotte-Pugh cutoff was 11.5. For MELD score > 20, the risk factors for death were: red cell requirements, liver dysfunction and donor's sodium. For the patients with hyponatremia the risk factors were: negative delta-MELD score, red cell requirements, liver dysfunction and donor's sodium. The regression univariated analyses came up with the following risk factors for death: score MELD > 25, blood requirements, recipient creatinine clearance pretransplant and age donor >50. After stepwise analyses, only red cell requirement was predictive. Patients with MELD score < 25 had a 68.86%, 50,44% and 41,50% chance for 1, 5 and 10-year survival and > 25 were 39.13%, 29.81% and 22.36% respectively. Patients without hyponatremia were 65.16%, 50.28% and 41,98% and with hyponatremia 44.44%, 34.28% and 28.57% respectively. Patients with IDR > 1.7 showed 53.7%, 27.71% and 13.85% and index donor risk <1.7 was 63.62%, 51.4% and 44.08%, respectively. Age donor > 50 years showed 38.4%, 26.21% and 13.1% and age donor <50 years showed 65.58%, 26.21% and 13.1%. Association with delta-MELD score did not show any significant difference. Expanded criteria donors were associated with primary non-function and severe liver dysfunction. Predictive factors for death were blood requirements, hyponatremia, liver dysfunction and donor's sodium. CONCLUSION: In conclusion MELD over 25, recipient's hyponatremia, blood requirements, donor's sodium were associated with poor survival.