Estudo ex vivo da elevação do pH em superfície radicular externa após agitação ultrassônica de diferentes pastas de hidróxido de cálcio / Assessment of pH increase in the external root surface after ultrasonic agitation of different calcium hydroxide pastes: Ex vivo study

Objetivo: O presente estudo teve por objetivo avaliar, ex vivo, a capacidade de elevação do pH da superfície radicular externa de diferentes pastas de hidróxido de cálcio (HC) utilizadas como medicação intracanal, além da influência da ativação ultrassônica (AUS) durante aplicação no interior do canal radicular. Métodos: Foram utilizados 100 incisivos humanos superiores unirradiculares, que tiveram os canais radiculares modelados e divididos aleatoriamente em seis grupos experimentais (n=15), de acordo com a pasta de HC, tendo como variáveis as medicações utilizadas e a ativação da pasta com AUS no momento da aplicação, além de um grupo controle (n=10): Pasta Calen; HC+clorexidina 2% gel (CX2%); e HC + água destilada. Os dentes foram mantidos imersos em água deionizada e as medidas do pH, verificadas nos períodos de 7, 14, 21 e 28 dias, com auxílio de pHmetro. Resultados: De acordo com os dados obtidos, verificou-se elevação do pH nos períodos de 7 e 14 dias em todos os grupos. Apenas os grupos em que foi utilizada a associação do HC com CX2% apresentou evolução com aumento significativo do pH ao longo dos períodos analisados (p<0,05). A ativação das pastas com AUS proporcionou incremento significativo dos valores de pH (p<0,05). Conclusão: De acordo com a metodologia empregada, pode-se concluir que todas as pastas utilizadas promovem elevação do pH no tecido dentinário, e a ativação das pastas com AUS influencia significativamente na elevação do pH no tecido dentinário (AU).

Objective: The aim of the present study was to evaluate, ex-vivo, the pH elevation capacity on the external root surface of different calcium hydroxide (HC) pastes, utilized as intracanal medication, it was also evaluated the influence of the ultrasonic activation at the application within the root canal. Methods: 100 human single root superior incisors were used, which had their root canals shaped and randomly divided into 6 experimental groups (n=15) according to the following HC pastes: Calen; HC + Chlorhex- idine 2% gel (CX2%); HC + distilled water, utilizing the medications and the ultrasonic activation of the paste at the time of the application as variables and 1 control group (n=10). The teeth were kept immersed in deionized water and the pH parameters were verified in 7, 14, 21 and 28 days with a pH measurement machine. Results: According to the data obtained, pH was elevated in the first week in all groups. Only the groups which the association of HC with CX2% was made, did show a significant increase in the pH level over the analyzed periods (p < 0,05). The activation of the pastes with US provided a significant increase in pH values (p < 0,05). Conclusion: According to the methodology used, we can conclude that all the HC pastes used, promote pH elevation in dentin tissue. And the acti- vation of the pastes with US significantly influences the pH increase in dentin tissue

Ácido 2-4 diclorofenoxiacético, un herbicida olvidado: reporte de dos casos / 2-4 dichlorophenoxyacetic acid, a forgotten herbicide: Two case report / Ácido 2-4 diclorofenoxiacético, um herbicida esquecido: reporte de dois casos

Los plaguicidas están entre las principales causas de intoxicación por sustancias químicas en Colombia. Entre ellos se cuentan herbicidas como el paraquat, el glifosato y el ácido 2,4-diclorofenoxiacético (2,4-D). Este último es uno de los herbicidas más usados en el mundo y la intoxicación por causa de este tiene una presentación similar a la intoxicación por inhibidores de la colinesterasa. El abordaje clínico de la intoxicación por 2,4-D es un reto para el primer respondiente, pues el cuadro sintomático es amplio dados los diferentes efectos de la sustancia, entre los que están el gastrointestinal, el metabólico, el renal, el neurológico, y, por supuesto, el toxicológico. Si bien la alcalinización urinaria es una piedra angular del manejo, cada vez hay más información sobre la efectividad y seguridad del uso de la hemodiálisis en casos graves. En este reporte se presentan los casos de dos pacientes con ingesta de 2,4-D, los únicos reportados en Colombia.

In Colombia one of the main sources of intoxication for chemical compounds are pesticides, finding in this groups herbicides like Paraquat, Glyphosate and 2,4-D, the last is one of the most used herbicides worldwide, finding similar clinical manifestations from those intoxications due to cholinesterase inhibitors. The access to this patient might represent a great challenge for the primary responder, because the symptomatic manifestations are wide due to the different risks it configures, like gastrointestinal, metabolic, renal, neurologic, and toxicological risk. Urinary alkalization was the recommended strategy for the management of this intoxication, but the evidence so far shows better safety and effectiveness using hemodialysis in the most severe cases. Then, the clinical cases of two patients with 2,4-D intake are presented, being those the only ones reported in Colombia so far.

Os praguicidas estão entre as principais causas de intoxicação por substâncias químicas na Colômbia. Entre eles se encontram herbicidas como o Paraquat, o glifosato e o ácido 2,4-diclorofenoxiacético (2,4-D). Este último é um dos herbicidas mais usados no mundo e a intoxicação por causa deste tem uma apresentação similar à intoxicação por inibidores da colinesterase. A abordagem clínica da intoxicação por 2,4-D é um desafio para o primeiro respondente, pois o quadro sintomático é amplo dados os diferentes efeitos da substância, entre os que está o gastrointestinal, o metabólico, o renal, o neurológico, e, por suposto, o toxicológico. Se bem que a alcalinização urinária é uma pedra angular do manejo, cada vez mais há mais informação sobre a efetividade e segurança do uso da hemodiálise nos casos graves. Neste reporte se apresentam os casos de dois pacientes com ingestão de 2,4-D, os únicos reportados na Colômbia.

Evaluation of alkali and thermotolerant lipase from an indigenous isolated Bacillus strain for detergent formulation

Background: Lipases are used in detergent industries to minimise the use of phosphate-based chemicals in detergent formulations. The use of lipase in household laundry reduces environmental pollution and enhances the ability of detergent to remove tough oil or grease stains. Results: A lipase-producing indigenous Bacillus subtilis strain [accession no. KT985358] was isolated from the foothills of Trikuta mountain in Jammu and Kashmir, India. The lipase (BSK-L) produced by this strain expressed alkali and thermotolerance. Lipase has an optimal activity at pH 8.0 and temperature 37°C, whereas it is stable at pH 6.0­9.0 and showed active lipolytic activity at temperatures 30 to 60°C. Furthermore, lipase activity was found to be stimulated in the presence of the metal ions Mn2+, K+, Zn2+, Fe2+ and Ca2+. This lipase was resistant to surfactants, oxidising agents and commercial detergents, suggesting it as a potential candidate for detergent formulation. BSK-L displayed noticeable capability to remove oil stains when used in different washing solutions containing buffer, lipase and commercial detergent. The maximum olive oil removal percentage obtained was 68% when the optimum detergent concentration (Fena) was 0.3%. The oil removal percentage from olive oil-soiled cotton fabric increased with 40 U/mL of lipase. Conclusions: This BSK-L enzyme has the potential for removing oil stains by developing a pre-soaked solution for detergent formulation and was compatible with surfactants, oxidising agents and commercial detergents.

Co-production of hydrogen and ethanol by Escherichia coli SS1 and its recombinant

Background: The development of a potential single culture that can co-produce hydrogen and ethanol is beneficial for industrial application. Strain improvement via molecular approach was proposed on hydrogen and ethanol co-producing bacterium, Escherichia coli SS1. Thus, the effect of additional copy of native hydrogenase gene hybC on hydrogen and ethanol co-production by E. coli SS1 was investigated. Results: Both E. coli SS1 and the recombinant hybC were subjected to fermentation using 10 g/L of glycerol at initial pH 7.5. Recombinant hybC had about 2-fold higher cell growth, 5.2-fold higher glycerol consumption rate and 3-fold higher ethanol productivity in comparison to wild-type SS1. Nevertheless, wild-type SS1 reported hydrogen yield of 0.57 mol/mol glycerol and ethanol yield of 0.88 mol/mol glycerol, which were 4- and 1.4-fold higher in comparison to recombinant hybC. Glucose fermentation was also conducted for comparison study. The performance of wild-type SS1 and recombinant hybC showed relatively similar results during glucose fermentation. Additional copy of hybC gene could manipulate the glycerol metabolic pathway of E. coli SS1 under slightly alkaline condition. Conclusions: HybC could improve glycerol consumption rate and ethanol productivity of E. coli despite lower hydrogen and ethanol yields. Higher glycerol consumption rate of recombinant hybC could be an advantage for bioconversion of glycerol into biofuels. This study could serve as a useful guidance for dissecting the role of hydrogenase in glycerol metabolism and future development of effective strain for biofuels production.

The influence of pH, polyethylene glycol and polyacrylic acid on the stability of stem bromelain

Enzyme stability is critical in biotechnology, pharmaceutical and cosmetic industries. Investigations on this subject have drawn attention because of its practical application. Bromelain is a thiol-endopeptidase, obtained from pineapple (Ananas comosus), known for its clinical and therapeutic applications, particularly to selective burn debridement and improvement of antibiotic action and anti-inflammatory activities. To date, the use of bromelain in pharmacological or industrial applications is limited, due to commercial availability, costs, and sensitivity to pH and temperature. Therefore, a better understanding of enzyme stability would be of great interest. The aim of this study was to evaluate bromelain activity and stability in several pH (2.0 to 8.0) and in polyethylene glycol and polyacrylic acid solutions. We observed that bromelain was able to maintain its stability at pH 5.0 for the temperatures studied. PEG solutions increased bromelain stability, but PAA solutions had the opposite effect.

Estabilidade de enzimas é uma questão fundamental em indústrias biotecnológicas, farmacêuticas e cosméticas. As investigações sobre o assunto têm chamado a atenção por sua aplicação prática. A bromelina é uma tiol-endopeptidase, obtida a partir do abacaxi (Ananas comosus). É conhecida por suas aplicações clínicas e terapêuticas, especialmente para desbridamento seletivo de queimaduras, melhoria de ações antibiótica e de atividades anti-inflamatórias. Até o momento, a utilização da bromelina em aplicações farmacológicas industriais é limitada, devido à disponibilidade comercial, os custos, a sensibilidade ao pH e temperatura. Portanto, a maior compreensão da estabilidade desta enzima seria de grande interesse. O objetivo deste estudo foi avaliar a estabilidade da atividade da bromelina em vários pH (2,0 a 8,0) e em soluções de polietilenoglicol e de ácido poliacrílico. Observamos que a bromelina foi capaz de manter a sua estabilidade em pH 5.0, em todas as temperaturas estudadas. Soluções de PEG aumentaram a estabilidade da bromelina, enquanto que soluções de PAA obtiveram efeito oposto.

Computation of interactive effects and optimization of process parameters for alkaline lipase production by mutant strain of Pseudomonas aeruginosa using response surface methodology

Alkaline lipase production by mutant strain of Pseudomonas aeruginosa MTCC 10,055 was optimized in shake flask batch fermentation using response surface methodology. An empirical model was developed through Box-Behnken experimental design to describe the relationship among tested variables (pH, temperature, castor oil, starch and triton-X-100). The second-order quadratic model determined the optimum conditions as castor oil, 1.77 mL.L-1; starch, 15.0 g.L-1; triton-X-100, 0.93 mL.L-1; incubation temperature, 34.12 ºC and pH 8.1 resulting into maximum alkaline lipase production (3142.57 U.mL-1). The quadratic model was in satisfactory adjustment with the experimental data as evidenced by a high coefficient of determination (R²) value (0.9987). The RSM facilitated the analysis and interpretation of experimental data to ascertain the optimum conditions of the variables for the process and recognized the contribution of individual variables to assess the response under optimal conditions. Hence Box-Behnken approach could fruitfully be applied for process optimization.

Soluciones de hipoclorito de sodio en Endodoncia y factores que varían la eficiencia de la solución / odium hypochlorite solutions in endodontics and efficiency factors that vary the solution

La irrrigación es un paso tan importante en la terapia endodóntica, igual que otro como la apertura, correcta instrumentación y la obturación. EL conocimiento de las propiedades químicas, factores que influyen en su eficiencia y la correcta utilización de la solución irrigadora, cumple un rol muy importante. La solución de hipoclorito de sodio, un liquido claro, pálido, verde amarillento, extremadamente alcalino de pH 11 a 12 y con fuerte olor clorino, fue utilizada por más de 70 años en endodoncia por su propiedades anti-bacteriana y de disolución de tejidos. Estas propiedades la convierten en la solución irrigadora más utilizada en endodoncia a pesar de algunas desventajas como la citotoxicidad. El objetivo de este trabajo es describir las propiedades antibacteriana, disolución del tejido, debridamiento, lubricación y la baja tensión superficial de la solución, y los factores que aumentan la eficacia de la solución como temperatura, pH, concentración, activación ultrasónica y combinación con otras sustancias. El propósito de este trabajo es dar a conocer las propiedades de la solución de hipoclorito de sodio y los factores que afectan a la misma para poder disminuir sus ventajas como toxicidad manteniendo o aumentando sus ventajas como la disolución de tejidos y efectos antibacterianos.

Ph salival y su relacion con la periodontitis severa de pacientes adultos con síndrome de down / Salival ph related to severe periodontitis in adults down syndrome patient

Objetivo. Relacionar el pH salival con la periodontitis severa de pacientes adultos con síndrome de Down, comparados con un grupo control. Material y método. Es un estudio epidemiológico, observacional, analítico de casos y controles, de corte transversal. La muestra estuvo constituida por 43 adultos entre 18 a 42 a más años con Síndrome de Down comparados en edad y género con 43 adultos sin síndrome de Down: 44,2% hombres y 55,8% mujeres. Se midieron los parámetros clínicos periodontales. El pH salival ha sido medido con un peachímetro digital. Los datos fueron analizados usando SPSS, versión 15. Resultados. El pH salival basal no estuvo asociado con la periodontitis que presentan los pacientes adultos con síndrome de Down. Tampoco hubo diferencia significativa de la periodontitis cuando se comparó con el grupo control (p > 0,05). El pH salival de los pacientes Down fue de 6,97 vs 6,99 de los pacientes del grupo control (p > 0,05). La periodontitis crónica severa localizada y generalizada tuvo mayor incidencia en pacientes con síndrome de Down. Hubo diferencia significativa comparada con el grupo control (p < 0,05). En el grupo Down [OR = 2,3 (0,4-12,8) [ (95% vs 1,6(0,3-9,4) ] grupo control (p>0,05). Conclusiones. El pH alcalino es un factor de riesgo para desarrollar periodontitis en adultos con síndrome de Down.

Objective. To relate the saliva pH with severe periodontitis in adult population with Down syndrome compared with a control group. Material and method. This is an epidemiological, observational, case-controls and transversal study. The sample was constituted by 43 adults without Down syndrome: 44.2% men and 55.8% women. Clinical periodontal parameters were measured. The saliva pH was measured using a digital pH meter. Data were analyzed by SPSS. 15. Results. Salival pH is not related to periodontitis of adults with Down Syndrome neither with control group, p>0.05 Down Syndrome adults showed a pH of 6.97 vs 6.99 of controls, p>0.05. Chronic severe periodontitis showed higher incidence, 23.3%, than 20% showed by control group. [OR = 2.3 (0.4 – 12.8) IC 95% vs 1.6 (0.3 – 9.4)] control group: p>0.05. Conclusions. Alkaline pH is a risk factor to raise periodontitis in Down syndrome adults.

Análise da formação de carbonato de cálcio pela reação do hidróxido de cálcio com diferentes veículos anestésicos / Analysis of calcium carbonate formation from the reaction of calcium hydroxide with different anesthetic vehicles

Objetivo: Avaliar in vitro a formação de carbonato de cálcio (CaCO3) nas pastas de hidróxido de cálcio e seu pH, utilizando cinco veículos diferentes.Método: Foi utilizado o hidróxido de cálcio pró-análise e como veículos os anestésicos Septodont (mepivacaína 3% sem vasoconstritor), Mepiadre (mepivacaína 2% com epinefrina 1:100.000), Alphacaine (lidocaína 2% com epinefrina 1:100.000) e Novocol (lidocaína a 2% com fenilefrina 1:2.500) e água destilada milliQ (Millipore) como controle. Ependorfes com hidróxido de cálcio (0,8g) foram misturados em agitador (Phoenix AP 56) com os solventes (0,8 mL) até obtenção de uma pasta homogênea e armazenados (37 ºC±1). Cada solução anestésica constituiu um grupo analisado em três períodos de tempo: inicio, sete e quatorze dias (n=9). A quantidade de (CaCO3) foi determinada através de titulometria (0,1N de H2SO4) e o pH das soluções anestésicas e das pastas aferidos através de phmetro (Micronal). Análise de variância (ANOVA) e comparações múltiplas com Schefee foram empregados para verificar o comportamento dos valores obtidos entre os tempos testados para cada grupo e entre os grupos entre si nos períodos de tempo.Resultados: O pH das pastas ficou entre 12,46 e 12,88 imediatamente após a mistura. O grupo controle apresentou um maior percentual de formação de CaCO3 aos 14 dias de armazenamento enquanto que Novocol e Alphacaine maior formação nos tempos iniciais e 7 dias. Os demais grupos (Scandicaine e Mepiadre) não apresentaram diferenças estatisticamente significante entre os períodos de tempo avaliados. No entanto, entre os grupos no mesmo período de tempo, apenas aos 7 dias foi possível observação de alteração estatisticamente significativa no anestésico Novocol. Conclusão: O pH das pastas se mostrou elevado (entre 12.46 e 12.88), imediatamente após a mistura e que houve a formação de (CaCO3) nas pastas de hidróxido de cálcio independente do veículo empregado.

Estudo da capacidade alcalinizante de tampões metabolizáveis em bovinos sadios / The alkalinizing effects of different metabolizable buffers in healthy steers

Seis novilhos mestiços, com cerca de 250kg e um ano de idade, foram infundidos, no decorrer de quatro horas, com cinco litros de diferentes soluções isotônicas de sais sódicos, com 150mM/l de bicarbonato, acetato, propionato, lactato L, lactato racêmico e cloreto (controle), em delineamento em quadrado latino (6x6). Análises hemogasométricas e do pH urinário foram determinadas no decorrer da infusão - zero, primeira e quatro horas - e após o seu término, na oitava hora. O pH do sangue foi maior nos animais infundidos com os tampões que nos infundidos com cloreto; teores mais elevados de bicarbonato e de excesso de ácido-base sanguíneos foram obtidos na quarta e oitava hora nos infundidos com bicarbonato e lactato; o mesmo ocorreu com a pressão de CO2 na oitava hora. Os resultados indicam que os tratamentos com Bicarbonato e lactato proporcionam acúmulo de tampões no sangue e geram discreta alcalose metabólica, compensada organicamente por leve retenção de CO2. a infusão com bicarbonato de sódio causa elevação do pH urinário

Six healthy crossbred yearling 250kg steers were infused intravenously, during four hours, with five liters of each of the six different isotonic solutions of sodium salts containing 150 mMol/l of the bicarbonate, acetate, propionate, L-lactate, D and L-lactate and chloride in a 6 x 6 latin square experimental design. Blood was collected from the jugular vein, anaerobically, for blood gas analysis, samples were obtained at different times throughout the infusion (zero, 1st, 4th and 8th h ). Urine was collect for determining the pH at the same schedule. Higher blood pH was found in cattle infused with all buffers than the chloride infused animals; higher level of blood bicarbonate and base excess were obtained at 4th and 8th h with bicarbonate and L-lactate, as well as with pCO2 at the 8th h. These results show that treatments with B and L lead to a slight accumulation of buffers in the blood, and generate a discrete metabolic alkalosis compensated organically by a small retention of CO2. Best alkalinizing effects are obtained by bicarbonate and L-lactato infusions. Bicarbonate infusions causes a high urinary pH

Resistance of diethylenetriaminepentaacetic acid to anaerobic biodegradation

Kraft mills are responsible for the massive discharge of highly polluted effluents, and new bleaching processes (i.e. Total Chlorine Free (TCF)) is presented as a feasible option to reduce this environmental impact. However, increased TCF pulp production is accompanied by an increase in chelate use. The most commonly used chelates, ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DPTA), are considered to be relatively persistent substances in water treatment plants, and consequently environmentally critical compounds. The purpose of this work is to investigate DPTA behaviour in an anaerobic system. An Anaerobic Filter (AF) was operated with three different DPTA load rates (LRDPTA = 0.07 - 0.28 gDPTA/L×d), and the operating strategy was to maintain the anaerobic system stable during the entire operation (alkalinity ratio below 0.3). The AF's maximum Chemical Oxygen Demand (COD) removal was 59 percent, whereas the Biological Oxygen Demand (BOD5) was around 95 percent. However, only 5 percent of DPTA removal was observed under anaerobic conditions during the first operating period. Scanning electronic microscopy indicates that the operating system reduced microorganism biodiversity.

Evaluación de las aplicaciones locales de una solución limpiadora suave con Dinafitol de Bardana y pH8: estudio realizado en consulta privada / Evaluation of the local application of a mild cleansing solution: study carried out in private consultation

Estudio realizado en consulta privada de los 17 médicos participantes, en 150 pacientes con vulvovaginitis, de los que se reportan 148 casos provenientes de tres principales ciudades del Ecuador (Guayaquil, Quito y Cuenca).Tipo de estudio: Abierto, multicéntrico, no comparativo.Objetivo: Evaluar la eficacia y tolerancia de una solución limpiadora suave con contenido de Bardana, en el período previo al tratamiento específico, como ayuda en el control del prurito y eritema presentes en las vulvovaginitis.Material y método: Se utilizó una solución limpiadora suave con contenido de Dinafitoles de Bardana y nivel de pH 8. Fueron reclutadas 150 pacientes de acuerdo a los criterios de inclusión, no inclusión y exclusión. La sintomatología fue evaluada al inicio y al final del estudio. Se recomendó el uso del producto en higiene local dos veces al día por siete días mientras se esperaba el resultado del examen cito bacteriológico vaginal.Resultados:•98.0% de mejoría y desaparición del prurito.•96.5% de mejoría y desaparición del eritema.En cuanto a la tolerancia al producto utilizado, el 95.3% reportó la calificación de “buena”.Conclusión: Se logró demostrar la utilidad de la solución limpiadora suave con pH8 y contenido de Dinafitol de Bardana, concluyendo que su utilización está justificada en los casos de vulvovaginitis y que, gracias a la tolerancia y aceptación de las pacientes se puede recomendar también su uso cotidiano en la higiene íntima y corporal. Por los resultados obtenidos, podemos considerar el uso de esta solución limpiadora como de primera elección en el manejo de las patologías relacionadas con el prurito y eritema y como un excelente coadyuvante en el tratamiento etiológico de las vulvovaginitis en las que con frecuencia advertimos la presencia de esta sintomatología.

Study carried out in the private consultation of 17 doctors selected to participate in the study that included 150 patients with vulvovaginitis, of which 148 cases are reported from in the three main cities of the Ecuador, (Guayaquil, Quito and Cuenca). Type of study: Open, multicentral, not comparative. Objective: To evaluate the effectiveness and tolerance of a mild cleansing solution, containing Bardana, during the period prior to a specific treatment, in order to help the control of pruritus and erythema present in the vulvovaginitis. Material and method: A mild cleansing solution with a pH level 8 was used. 150 patients were recruited according to the inclusion and exclusion criteria of the study. The symptoms were evaluated at the beginning and at the end of the study. The use of the product was recommended twice a day for seven days while expecting the results of the bacteriological vaginal exam.Results:•98.0% of improvement and disappearance of pruritus.•96.5% of improvement and disappearance of erythema. As for the tolerance to the use of product, 95.3% of the patients reported it as “good”. Conclusion: It was possible to demonstrate the how important is the use of the mild cleansing solution with a pH 8. We conclude that its use is justified in the case of vulvovaginitis and that thanks to its tolerance and the patients' acceptance, it may also be recommended to be used daily in the intimate and corporal hygiene. With the reported results, one can consider the use of this mild cleansing solution as the first election in the handling of pathologies related with pruritus and erythema and as an excellent help for etiological treatment of the vulvovaginitis in those that frequently notice the presence of this symptoms.