Comparison of the High Cycle Fatigue Behavior of the Orthodontic NiTi Wires: An in Vitro Study

Abstract Objective: To compare the high-cycle fatigue behavior of four commercially available NiTi orthodontic wires. Material and Methods: Twelve NiTi orthodontic wires, round, 0.016-in, three per brand, were selected and divided into four groups: G1 - Heat-activated NiTi, G2 - Superelastic NiTi, G3 - Therma-Ti, and G4 - CopperNiTi. The atomic absorption spectrometry method was used to determine the chemical composition of investigated NiTi wires. We also performed a fatigue test at three-point bending using a universal testing machine for 1000 cycles in a 35 °C water bath. For the first and thousandth cycle, the average plateau load and the plateau length were determined in the unloading area of the force versus displacement diagram. In addition, we calculated the difference between the average plateau load of the first and thousandth cycle (∆F), as well as the difference between the plateau length of both cases (∆L). Results: According to our results, there were no significant differences between the average plateau load of the first and thousandth cycles of each group (p>0.05) and in the plateau length of the first and thousandth cycles of the groups (p>0.05). Conclusion: There were no significant differences between the groups changing the superelasticity property after high-cycle fatigue.

Bioconcentración de metales pesados (Zn, Hg, Pb) en tejidos de Ariopsis felis y Diplodus annularis en el río Ranchería, norte de Colombia / Bioconcentration of heavy metals (Zn, Hg, Pb) in tissues of Ariopsis felis and Diplodus annularis in the Ranchería river, Northern Colombia

RESUMEN La contaminación por metales pesados en los ecosistemas acuáticos en el planeta es una de las más severas problemáticas que comprometen la seguridad alimentaria a nivel local, regional y global. En este estudio, se aborda el problema específico de la bioconcentración de mercurio (Hg), plomo (Pb) y Zinc (Zn) en los tejidos orgánicos de 2 de las especies de peces (Ariopsis felis y Diplodus annularis) de mayor importancia alimenticia para los pobladores rivereños del río Ranchería, al norte de Colombia. Las muestras de tejido orgánico se sometieron a una digestión ácida (HNO3 y HClO 4 en relación 3:1) y la cuantificación de los metales se realizó por espectrofotometría de absorción atómica. Adicionalmente, se midieron los niveles de los metales en el sedimento, con el objeto de determinar índices de calidad medioambientales, lo que permitió determinar que los metales pesados no presentan riesgo para los organismos acuáticos que habitan en esta zona. Se encontraron diferentes valores de concentración de metales pesados: en orden decreciente, Zn > Hg > Pb, en sedimento, y Hg > Zn > Pb, en el tejido biológico. Los resultados muestran que las concentraciones de los metales pesados presentes en el tejido de los peces y en el sedimento guardan una correlación positiva y una regresión lineal estadísticamente significativa (p = 0,001, p < 0,05). La presencia de metales pesados en el sedimento del río y de bioconcentrados en los peces podría derivarse de fuentes puntuales y difusas relacionadas con actividades agrícolas, pecuarias, mineras y aguas residuales.

ABSTRACT Heavy metal pollution in aquatic ecosystems in the area is one of the most severe problems that compromise food security at the local, regional and global levels. In this study, the specific problem of the bioconcentration of mercury (Hg), lead (Pb), and Zinc (Zn) in 2 of the higher nutritional importance fish species (Ariopsis felis and Diplodus annularis) for the riverside inhabitants of the Ranchería river, in northern Colombia, is addressed. The organic tissue samples were subjected to acid digestion (HNO3 and HClO4 in a 3:1 ratio), and the quantification of metals was carried out by atomic absorption spectrophotometry. Additionally, the levels of metals in the sediment were measured, in order to determine environmental quality indices. This allow to determine that heavy metals do not present a risk to the aquatic organisms that inhabit this area. Different heavy metal concentration values were found: in decreasing order, Zn> Hg> Pb in sediment, and Hg> Zn> Pb in biological tissue. The results reveal that the concentrations of heavy metals present in fish tissue and sediment show a positive correlation, and a statistically significant linear regression (p = 0,001, p < 0,05). The presence of heavy metals in river sediment and bioconcentrates in fish could derive from point and diffuse sources related to agricultural, livestock, mining and wastewater activities.

Evaluation the Health Impact of Some Heavy Metals in Milk from Markets

This study focuses on the heavy metals concentrations (Fe, Cu, Zn, Pb, and Cd) in certain common milk species are collected from Iraqi markets using Flame Atomic Absorption Spectrophotometer-6300 AA, Shimadzu, Japan, respectively. This study shows the pollution in the environment obtained by heavy metals. The results showed that Cr, Cd, Cu, Zn, and Fe were varying according to the order: Zn>Fe>Cr>Cd>Cu. levels of heavy metals were 0.610(Cr), 0.125(Cd), 0.052(Cu), and 6.902(Zn), and 0.759(Fe). All the heavy metals were observed within maximum limit in milk. Overall, the number of analyzed heavy metals and sample size were limited in present study. Keywords: Heavy metals; Milk; Najaf; Flame atomic absorption; Spectrophotometer This study focuses on the heavy metals concentrations (Fe, Cu, Zn, Pb, and Cd) in certain common milk species are collected from Iraqi markets using Flame Atomic Absorption Spectrophotometer-6300 AA, Shimadzu, Japan, respectively. This study shows the pollution in the environment obtained by heavy metals. The results showed that Cr, Cd, Cu, Zn, and Fe were varying according to the order: Zn>Fe>Cr>Cd>Cu. levels of heavy metals were 0.610(Cr), 0.125(Cd), 0.052(Cu), and 6.902(Zn), and 0.759(Fe). All the heavy metals were observed within maximum limit in milk. Overall, the number of analyzed heavy metals and sample size were limited in present study

Niveles de cobre y zinc en diferentes etapas de la leche materna y la influencia del estado nutricional de madres lactantes / Levels of copper and zinc in different stages of breast milk and the influence of the nutritional state of nursing mothers

RESUMEN La leche humana materna tiene una composición única para proporcionar a los recién nacidos todos los nutrientes esenciales como proteínas, grasas, hidratos de carbono, minerales, vitaminas y otras substancias fisiológicamente activas, con el fin de suplir en cantidad y calidad las necesidades calóricas y nutricionales del lactante. El objetivo fue establecer las concentraciones totales de cobre y zinc en la leche materna en sus distintas etapas: calostro, de transición y madura, determinadas espectrométricamente y la influencia del estado nutricional de madres lactantes; estudio descriptivo transversal en madres entre 18 y 35 años, sanas y no fumadoras; los resultados evidencian una disminución en las concentraciones de cobre y zinc a medida que la lactancia va evolucionando, además, el promedio de índice de masa corporal de las madres en período de lactancia reflejaron sobrepeso. Concluimos que el contenido calórico de los oligoelementos de la leche materna es esencial para el crecimiento de los niños por los beneficios nutricionales e inmunológicos que proporciona, por lo que es importante que la madre se encuentre en un estado nutricional adecuado que permita suministrar los requerimientos adecuados al niño para su crecimiento y desarrollo.

ABSTRACT Human milk has a unique composition and provides newborns with all essential nutrients such as proteins, fats, carbohydrates, minerals, vitamins and other physiologically active substances, in order to supply in quantity and quality the caloric and nutritional needs of the infant. The objective of this study was to establish the total concentration of copper and zinc in breast milk in its different stages: colostrum, transitional and mature milk, determined spectrometrically and the influence of the nutritional status of nursing mothers. We conducted a descriptive cross-sectional study in healthy non-smoking mothers between 18 and 35 years of age. Lower concentrations of copper and zinc as lactation progressed were observed. The average of body mass index of nursing mothers reflected overweight. We concludes that the caloric content of the trace elements of breast milk is essential for the growth of children because of the nutritional and immunological benefits that it provides, so it is important that the mother has an adequate nutritional state that allows to supply the adequate requirements for the child to grow and develop.

Differences in mineral concentrations on hooves of horses, mules and donkeys / Diferenças nas concentrações de minerais nos cascos de equinos, muares e asininos

This study aimed to measure the concentrations of minerals in different regions and pigmentation of horses' hooves, mules and donkeys. A total of 20 Crioulo horses, 20 mules and 20 Pega donkeys were used. They formed two groups: pigmented (dark) or non-pigmented (bright) hooves. All animals were unshod and with adequate foot conformation. Females were non-pregnant and without foal and no animals were in training. Samples were collected from the hooves of all limbs in the regions of wall, sole and frog. The concentrations of calcium, magnesium, copper, iron and zinc were determined by atomic absorption spectrophotometry; sodium and potassium concentrations were determined by atomic emission spectrophotometry. Among the groups it was observed that the wall, sole and frog of donkeys' hooves presented higher concentrations of sodium and calcium and with the exception of the frog that also obtained higher levels of copper in this species. Mules had lower concentrations of zinc in the wall and the horses had higher concentrations of potassium and zinc in the sole and higher magnesium in the frog and wall. There was no difference (P>0.05) in concentrations regarding the pigmentation of the hooves. The different regions of the hooves in each group presented similar concentrations of minerals and it was regardless of the pigmentation. The mineral concentrations may be related to desirable functional properties of the donkeys' hooves. Pigmented and non-pigmented hooves have similar concentrations of minerals.

O objetivo desse trabalho foi mensurar os teores de minerais nas diferentes regiões e pigmentações dos cascos de equinos, muares e asininos. Utilizaram-se 20 equinos da raça Crioula, 20 muares e 20 asininos da raça Pêga. Formaram-se dois grupos conforme os cascos pigmentados (escuros) e não pigmentados (claros). Todos os animais estavam desferrados e com adequada conformação podal e as fêmeas estavam não gestantes e sem potro ao pé e nenhum animal estava em treinamento. Amostras foram coletadas dos cascos de todos os membros nas regiões de parede, sola e ranilha. As concentrações de cálcio, magnésio, cobre, ferro e zinco foram determinadas por espectrofotometria de absorção atômica e as concentrações de sódio e potássio foram determinadas por espectrofotometria de emissão atômica. Entre os grupos observou-se que a parede, sola e ranilha nos asininos apresentaram maiores valores de sódio e cálcio e, exceto para a ranilha, também obteve-se maiores teores de cobre nesta espécie. Os muares apresentaram menores teores de zinco na parede e, os equinos, maiores teores de potássio e zinco na sola e ranilha e de magnésio na ranilha e parede. Não houve diferença (P>0,05) nos teores dos minerais quanto à pigmentação dos cascos. As diferentes regiões dos cascos em cada grupo apresentaram teores similares de minerais e este independeu da pigmentação. As variações dos teores de minerais entre os grupos podem estar relacionados a propriedades funcionais desejáveis dos cascos dos asininos. Cascos pigmentados e não pigmentados apresentam teores similares dos minerais.

Concentración de titanio en tejido respiratorio obtenido de autopsias en residentes de la ciudad de México / Concentration of titanium in respiratory tissue obtained from autopsies in Mexico city residents

RESUMEN Objetivos. Cuantificar la cantidad de titanio (Ti) en tejido respiratorio obtenidas por autopsia en personas que residieron en la Ciudad de México. Materiales y métodos. Se realizó un estudio exploratorio en el cual se obtuvieron 216 muestras de tejido respiratorio de lóbulos pulmonares y nódulos linfáticos peribronquiales, procedentes de autopsias médico legales de 36 cadáveres con antecedente de haber residido un mínimo de dos años en la Ciudad de México. Se realizaron análisis histopatológicos de las muestras y se cuantificó el Ti existente en ellas mediante plasma de inducción acoplado a la espectrofotometría de absorción atómica. Resultados. La cantidad de Ti en tejido respiratorio se distribuyó entre 0 microgramos de Ti en tejido seco (µg Ti/g ts) y 39,7 µg Ti/g ts, se identificó la presencia de Ti distribuido hasta en seis veces mayor cantidad en los nódulos linfáticos que en lóbulos pulmonares. El análisis de conglomerados mostró que la muestra estaba conformada por cuatro grupos de individuos agrupados de acuerdo a la cantidad y distribución del Ti en el tracto respiratorio bajo, a la edad, índice de masa corporal, lugar y tiempo de residencia en la ciudad de México. Conclusiones. Debido al patrón de distribución observado el Ti encontrado en las muestras de tejido respiratorio podría provenir del aire urbano, la cantidad de Ti en conjunto con otros elementos podría ser causante de patologías respiratorias.

ABSTRACT Objetivos. To quantify the levels of titanium (Ti) in respiratory tissue obtained by autopsy in people who resided in Mexico City. Materials and Methods. An exploratory study was conducted in which 216 samples of respiratory tissue from pulmonary lobes and peribronchial lymph nodes were obtained from legal medical autopsies of 36 corpses with a minimum of two years of residence in Mexico City. Histopathological analyses of the samples were performed and the Ti existing in them was quantified by induction plasma coupled to atomic absorption spectrophotometry. Results. The amount of Ti in respiratory tissue was distributed between 0 micrograms of Ti in dry tissue (µg Ti/g ts) and 39.7 µg Ti/g ts; the presence of Ti was identified as distributed in up to six times a higher quantity in the lymph nodes than in pulmonary lobes. Cluster analysis showed that the sample consisted of four groups of individuals grouped according to the amount and distribution of Ti in the lower respiratory tract, age, body mass index, place and time of residence in Mexico City. Conclusions . Due to the distribution pattern observed, Ti found in respiratory tissue samples may come from urban air; the amount of Ti in conjunction with other elements may be the cause of respiratory pathologies.

Identification of Lead Exposure Through Saliva and the Occurrence of Gingival Pigmentation at Fuel Station Indonesian Officers

Objective: To identify the exposure of lead through saliva and the presence of gingival pigmentation in the risk group. Material and Methods: The type of this research is analytic observational with cross-sectional study design. The sample consisted of 40 subjects, who were divided into two groups of 20 each: G1: Gasoline Fuel Station and G2: Officer in Dental Hospital. To determine the level of leads in saliva is measured by atomic absorption spectrophotometry and assessment of the severity of lead-gingival lead line in this study based on the area of the gingival surface based on the number of dental areas. The data were analyzed with the t-test and Chi-square test. The level of significance was set at 5%. Results: The average lead content in saliva group exposed was 6.66 µg / ml and control group 4.72 µg / ml (p≤0.05). There is a correlation between gingival lead line incidence with exposure to lead (OR = 3.33; p = 0.001). Conclusion: The identification of exposure to lead poisoning can be determined by examination in saliva and ginggiva state, it is proven that the risk of gingival lead (Ginggival Lead Line) in the worker group at the gas station station is 3.3 times more risk than the control group. Occupational safety factors are important for workers at high risk of exposure to the element of lead for additional education on the importance of using masks to prevent the severity of the occurrence of lead effects on overall health.

A Comparison of Serum Lead Status among Elderly Osteopaenic Patients, Elderly Osteoporotic Patients and Healthy Controls / Comparación del estado de plomo sérico entre los pacientes osteopénicos mayores de edad, los pacientes osteoporóticos mayores de edad, y los controles sanos

ABSTRACT Objective: It is proposed that in some conditions such as pregnancy and osteoporosis where the bone turnover rate is high, there is mobilization of various minerals including lead (Pb) from bone to blood. This study aimed to determine if there were any differences in serum Pb levels among elderly osteopaenic patients, elderly osteoporotic persons and healthy controls. Methods: Fifty-four elderly persons (26 men and 28 women) from the Amirkola Health and Ageing Project, Iran, were included in this study. The diagnosis of osteopaenia and osteoporosis was based on spine and femur bone mineral density (BMD) measurements. After blood sampling, serum Pb levels were analysed by the method of atomic absorption spectrophotometry. Results: According to the BMD measurements, 19 persons had normal BMD, while 16 had osteopaenia and 19 suffered from osteoporosis. The differences in body mass index in these three groups were statistically significant (p < 0.001). The patients with osteoporosis had the highest levels of alkaline phosphatase and the highest rate of bone turnover. The mean ± standard deviation of the serum Pb levels in these groups were 236.8 ± 98.0, 270.0 ± 81.5 and 258.3 ± 57.5 μg/L, respectively, and the differences were not statistically significant (p = 0.467). Conclusion: No statistically significant differences in serum Pb levels were observed in healthy controls compared with osteopaenic persons and osteoporotic persons. This suggests that mobilization of Pb from bone to blood in this population of elderly osteopaenic patients and elderly osteoporotic patients was similar to that in the healthy controls.

RESUMEN Objetivo: Se postula que en algunas condiciones como el embarazo y la osteoporosis donde el índice de recambio óseo es alto, hay movilización de varios minerales - incluyendo plomo (Pb) - de los huesos a la sangre. Este estudio tuvo como objetivo determinar si hubo diferencias en los niveles de plomo sérico entre los pacientes osteopénicos mayores de edad, los pacientes osteoporóticos mayores de edad, y los controles sanos. Métodos: Se incluyeron en este estudio 54 personas de edad avanzada (26 hombres y 28 mujeres) del Proyecto Amirkola de Salud y Envejecimiento, Irán. La diagnosis de la osteopenia y la osteoporosis se basó en mediciones de la densidad mineral ósea (DMO) de la espina dorsal y del fémur (DMO). Después del muestreo de sangre, los niveles séricos de Pb fueron analizados por el método de espectrofotometría de absorción atómica. Resultados: Según las mediciones de la DMO, 19 personas tenían DMO normal, mientras que 16 tenían osteopenia y 19 padecían osteoporosis. Las diferencias en el índice de masa corporal en estos tres grupos fueron estadísticamente significativas (p < 0.001). Los pacientes con osteoporosis tenían los niveles más altos de fosfatasa alcalina y el índice más alto de recambio óseo. La media ± desviación estándar de los niveles séricos de Pb en estos grupos fue de 236.8 ± 98.0, 270.0 ± 81.5 y 258.3 ± 57.5 μg/L, respectivamente, y las diferencias no fueron estadísticamente significativas (p = 0.467). Conclusión: No se observaron diferencias estadísticamente significativas en los niveles séricos de Pb en los controles sanos en comparación con las personas osteopénicas y las osteoporóticas. Esto sugiere que la movilización de Pb del hueso a la sangre en esta población de pacientes osteopénicos mayores de edad y pacientes osteoporóticos mayores de edad, era similar a la encontrada en los controles sanos.

Avaliação dos níveis de chumbo e mercúrio em população exposta ambientalmente na Região Centro-oeste do Brasil / Evaluación de los niveles de plomo y mercurio en población expuesta ambientalmente en la región centro-oeste de Brasil / Lead and mercury levels in an environmentally exposed population in the Central Brazil

O objetivo foi avaliar o nível de exposição ao chumbo e mercúrio em população do Pantanal Mato-grossense, Brasil. Chumbo no sangue (Pb-S) (n = 119) e mercúrio na urina (Hg-U) (n = 109) de moradores da região foram determinados por espectrometria de absorção atômica. A comparação de médias e correlação entre as variáveis utilizaram o teste ANOVA e a regressão linear, respectivamente, com 95% de confiança. Pb-S médio foi 2,82 ± 1,53µg dL-1. A comparação de Pb-S estratificado por local de coleta (p ≤ 0,01), atividade laboral (p ≤ 0,01) e consumo de leite produzido na região (p ≤ 0,05) mostrou diferenças estatisticamente significativas. Também houve associações positivas entre Pb-S e local de coleta (p ≤ 0,01), profissão dos participantes (p ≤ 0,05), consumo de leite da região (p ≤ 0,01) e origem da água de consumo (p ≤ 0,01). A média de Hg-U foi 1,41 ± 0,98µg L-1. Os teores mostraram diferenças significativas apenas quanto à profissão dos participantes (p ≤ 0,01), e associações positivas surgiram entre Hg-U e atividade profissional (p ≤ 0,01) assim como índice de massa corporal dos sujeitos de estudo (p ≤ 0,01). As amostras apresentaram baixos níveis de chumbo e mercúrio, semelhantes àqueles encontrados em populações também expostas ambientalmente. Apesar dessas baixas concentrações, o conhecimento atual sobre toxicidade desses metais mostra que efeitos à saúde já podem ser sentidos em níveis antes considerados seguros, o que caracteriza o perigo.

El objetivo fue evaluar el nivel de exposición al plomo y mercurio en una población del Pantanal Mato-grossense, Brasil. El plomo en sangre (Pb-S) (n = 119) y mercurio en la orina (Hg-U) (n = 109) de los habitantes de esa región se determinó por espectrometría de absorción atómica. La comparación de medias y la correlación entre las variables utilizaron el test ANOVA y la regresión lineal, respectivamente, con un 95% de confianza. Pb-S medio fue 2,82 ± 1,53µg dL-1. La comparación de Pb-S estratificado por lugar de recogida (p ≤ 0,01), actividad laboral (p ≤ 0,01) y consumo de leche que se produjo en la región (p ≤ 0,05) mostró diferencias estadísticamente significativas. También hubo asociaciones positivas entre Pb-S y el lugar de recogida (p ≤ 0,01), profesión de los participantes (p ≤ 0,05), consumo de leche de la región (p ≤ 0,01) y origen del agua de consumo (p ≤ 0,01). La media de Hg-U fue 1,41 ± 0,98µg L-1. Los porcentajes mostraron diferencias significativas sólo respecto a la profesión de los participantes (p ≤ 0,01), y las asociaciones positivas surgieron entre Hg-U y la actividad profesional (p ≤ 0,01), así como índice de masa corporal de los sujetos de estudio (p ≤ 0,01). Las muestras presentaron bajos niveles de plomo y mercurio, semejantes a aquellos encontrados en poblaciones también expuestas ambientalmente. A pesar de esas bajas concentraciones, el conocimiento actual sobre toxicidad de estos metales muestra que los efectos sobre la salud, ya pueden ser apreciados en niveles antes considerados seguros, lo que caracteriza el peligro.

The objective was to assess the level of exposure to lead and mercury in a population in the Pantanal region in Mato Grosso State, Brazil. Blood lead (PbB) (n = 119) and urinary mercury (HgU) (n = 109) in local residents were measured by atomic absorption spectrometry. Comparison of means and correlations between variables used analysis of variance (ANOVA) and linear regression, respectively, with 95% confidence intervals. Mean PbB was 2.82 ± 1.53µg dL-1. The comparison of PbB stratified by collection site (p ≤ 0.01), work activity (p ≤ 0.01), and consumption of locally produced cow's milk (p ≤ 0.05) showed statistically significant differences. There were also positive associations between PbB and collection site (p ≤ 0.01), participants' profession (p ≤ 0.05), local milk (p ≤ 0.01), and source of drinking water (p ≤ 0.01). Mean HgU was 1.41 ± 0.98µg L-1. The levels only showed significant differences for participants' profession (p ≤ 0.01), and positive associations emerged between HgU and work activity (p ≤ 0.01) and body mass index (p ≤ 0.01). The samples showed low lead and mercury levels, similar to those found in other environmentally exposed populations. Despite these low concentrations, current knowledge on the toxicity of these metals shows that health effects can already be felt at levels that were previously considered safe, thus characterizing a health hazard.

Lead, Mercury, and Cadmium Exposure in the Korean General Population

BACKGROUND: Lead (Pb), mercury (Hg), and cadmium (Cd) are well-known environmental pollutants. They are unnecessary in the biological processes of humans. This study was performed to estimate the representative background exposure levels to the metals by measuring concentrations in whole blood of the Korean general population. METHODS: This population-based cross-sectional study included 4,000 subjects (1,886 males and 2,114 females) 0–83 years of age in 2010 and 2011. Adult subjects (≥ 19 years of age) were collected by sex- and age-stratified probability method, and preschool- and school-aged subjects were recruited by a cluster sampling method. Written consent was provided prior to blood sampling. Pb and Cd blood concentrations were determined by a flameless atomic absorption spectrophotometry, and blood Hg was analyzed by a direct Hg analyzer. RESULTS: The geometric mean, median and 95th percentile of blood Pb was 1.82 µg/dL, 1.83 µg/dL, and 3.78 µg/dL, respectively. The respective values were 2.92 µg/L, 2.87 µg/L, 9.12 µg/L for Hg, and 0.56 µg/L, 0.59 µg/L, 2.20 µg/L for Cd. Blood Pb and Hg were higher in males than in females, but no sex difference was observed, respectively, in subjects 0–4 years of age for Pb and in subjects less than 20 years for Hg. However, blood Cd was higher in females than in males and no sex difference was observed in subjects < 30 years of age. CONCLUSION: This study provides representative data of human exposure to Pb, Hg, and Cd covering whole age groups of the general population in Korea.

Research progress on identification and quality evaluation of glues medicines / 中国中药杂志

Glues medicines is a special kind of traditional Chinese medicine.As the market demand is large, the raw materials are in short supply and lacks proper quality evaluation technology, which causes inconsistent quality of products on the market. Its authentic identification and evaluation stay a problem to be solved. In this paper, the research progress of the methods and techniques of the evaluation of the identification and quality of glues medicines were reviewed. The researches of medicinal glue type identification and quality evaluation mainly concentrated in four aspects of medicinal materials of physical and chemical properties, trace elements, organic chemicals and biological genetic methods and techniques. The methods of physicochemical properties include thermal analysis, gel electrophoresis, isoelectric focusing electrophoresis, infrared spectroscopy, gel exclusion chromatography, and circular dichroism. The methods including atomic absorption spectrometry, X-ray fluorescence spectrometry, plasma emission spectrometry and visible spectrophotometry were used for the study of the trace elements of glues medicines. The organic chemical composition was studied by methods of composition of amino acids, content detection, odor detection, lipid soluble component, organic acid detection. Methods based on the characteristics of biogenetics include DNA, polypeptide and amino acid sequence difference analysis. Overall, because of relative components similarity of the glues medicines (such as amino acids, proteins and peptides), its authenticity and quality evaluation index is difficult to judge objectively, all sorts of identification evaluation methods have different characteristics, but also their limitations. It indicates that further study should focus on identification of evaluation index and various technology integrated application combining with the characteristics of the production process.

Demetallization of Enterococcus faecalis biofilm: a preliminary study

Abstract Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days. The following were used as irrigation solutions: 17% EDTA (pH 3, 7 and 10), 2.5% sodium hypochlorite (NaOCl) combined with 17% EDTA (pH 3, 7 and 10), distilled water (pH 3, 7 and 10), and 2.5% NaOCl. Each solution was kept in the root canal for five minutes. Fifteen uncontaminated root canals were irrigated with 17% EDTA (pH 3, 7 and 10). Six teeth were used as bacterial control. The number of calcium, iron, manganese and zinc ions was determined using flame atomic absorption spectrometry. Mean ± standard deviation (SD) values were used for descriptive statistics. Results Calcium chelation using 17% EDTA at pH 7 was higher than at pH 3 and 10, regardless of whether bacterial biofilm was present. The highest concentration of iron occurred at pH 3 in the presence of bacterial biofilm. The highest concentration of manganese found was 2.5% NaOCl and 17% EDTA at pH 7 in the presence of bacterial biofilm. Zinc levels were not detectable. Conclusions The pH of chelating agents affected the removal of calcium, iron, and manganese ions. The concentration of iron ions in root canals with bacterial biofilm was higher after the use of 17% EDTA at pH 3 than after the use of the other solutions at all pH levels.

Serum selenium and selenoprotein-P levels in autoimmune thyroid diseases patients in a select center: a transversal study

ABSTRACT Objective: Selenium (Se) supplementation has been used to help prevent the progression of Graves' ophthalmopathy (GO) and autoimmune thyroid diseases (AITD) patients. We investigated Se serum and selenoprotein P (SePP) levels in Graves' disease (GD) with and without GO, Hashimoto's thyroiditis (HT) patients and in 27 control individuals (C). Subjects and methods: We studied 54 female and 19 male patients: 19 with GD without GO, 21 GD with GO, 14 with HT and 19 with HT+LT4. Se values were measured using graphite furnace atomic absorption spectrophotometry. Serum SePP levels were measured by ELISA. Results: Median Se levels were similar among all groups; GD patients: 54.2 (46.5-61.1 μg/L), GO: 53.6 (43.5-60.0 μg/L), HT: 51.9 (44.6-58.5 μg/L), HT+LT4 54.4 (44-63.4) and C group patients: 56.0 (52.4-61.5 μg/L); P = 0.48. However, serum SePP was lower in GO patients: 0.30 (0.15-1.05 μg/mL) and in HT patients: 0.35 (0.2-1.17 μg/mL) compared to C group patients: 1.00 (0.564.21 μg/mL) as well as to GD patients: 1.19 (0.62-2.5 μg/mL) and HT+LT4 patients: 0.7 (0,25-1.95); P = 0.002. Linear regression analysis showed a significant relationship between SePP and TPOAb values (r = 0.445, R2 = 0.293; P < 0.0001). Multiple regression analysis found no independent variables related to Se or SePP. Conclusion: A serum Se concentration was lower than in some other countries, but not significantly among AITD patients. The low serum SePP levels in GO and HT patients seems to express inflammatory reactions with a subsequent increase in Se-dependent protein consumption remains unclear.

Dietary determinants of urinary molybdenum levels in Mexican women: a pilot study / Determinantes dietéticos de molibdeno urinario en mujeres mexicanas: un estudio piloto

Abstract: Objective: This study determined the main dietary sources of urinary molybdenum (Mo) concentrations in a sample of 124 pregnant women in Mexico. Materials and methods: Dietary data was collected during pregnancy, through a semi-qualitative food frequency questionnaire, with information of 84 foods. Urine Mo levels were determined by atomic absorption spectrometry, for at least two trimesters of pregnancy. The associations with Mo levels were estimated by generalized mixed effect regression models. Results: Between 5.8 to 12.7% of the samples were above the 95th percentile of urinary Mo distribution reported by National Health and Nutrition Examination Survey (NHANES) 2009-2010 for women (151 μg/L and 148 μg/g creatinine). After bootstrap resampling was conducted, women with high-consumption of hot peppers (β=1.34μg/g; 95% CI: 1.00-1.80; p= 0.05) had marginally higher urinary Mo concentration levels, creatinine adjusted, compared to women with low-consumption. Conclusion. Hot chili pepper consumption may contribute to body burden Mo levels in this population.

Resumen: Objetivo: Determinar las fuentes dietéticas de molibdeno (Mo) urinario en 124 mujeres embarazadas residentes en el estado de Morelos, México. Material y métodos: Mediante un cuestionario de frecuencia de consumo de 84 alimentos, se obtuvo información dietética durante el embarazo. Las concentraciones urinarias de Mo se determinaron por espectrometría de absorción atómica, en al menos dos trimestres del embarazo. La asociación se estimó mediante modelos de efectos mixtos generalizados. Resultados: Entre 5.8 y 12.7% de las muestras superaron el P95 (151 µg/L y 148 µg/g creatinina) de la distribución de Mo urinario reportado para mujeres por la Encuesta Nacional de Nutrición y Salud de Estados Unidos (NHANES) 2009-2010. El mayor consumo de chile (β=1.34μg/g; IC95%: 1.00-1.80; p=0.05) se asoció con concentraciones marginalmente mayores de Mo. Conclusión: Probablemente debido a los fertilizantes o el sistema de riego utilizado en su cultivo, el consumo de chile es una posible fuente de exposición a Mo, en esta población.

Role of Candida species from HIV infected children in enamel caries lesions: an in vitro study

Abstract Objectives This study analyzed the capacity of Candida spp. from dental biofilm of HIV infected (HIV+) children to demineralize primary molar enamel in vitro by Transversal Microhardness (TMH), Polarized Light Microscopy (PLM) and the quantity of calcium ions (Ca2+) released from the enamel. Material and Methods Candida spp. samples were isolated from the supragingival biofilm of HIV+ children. A hundred and forty (140) enamel blocks were randomly assigned to six groups: biofilm formed by C. albicans (Group 1); mixed biofilm formed by C. albicans and C. tropicalis (Group 2); mixed biofilm formed by C. albicans and C. parapsilosis (Group 3); mixed biofilm formed by C. albicans, C. parapsilosis and C. glabrata (Group 4); biofilm formed by C. albicans ATCC (Group 5) and medium without Candida (Group 6). Enamel blocks from each group were removed on days 3, 5, 8 and 15 after biofilm formation to evaluate the TMH and images of enamel were analyzed by PLM. The quantity of Ca2+ released, from Groups 1 and 6, was determined using an Atomic Absorption Spectrophotometer. The SPSS program was used for statistical analysis and the significance level was 5%. Results TMH showed a gradual reduction in enamel hardness (p<0.05) from the 1st to 15th day, but mainly five days after biofilm formation in all groups. The PLM showed superficial lesions indicating an increase in porosity. C. albicans caused the release of Ca2+ into suspension during biofilm formation. Conclusion Candida species from dental biofilm of HIV+ children can cause demineralization of primary enamel in vitro.

Evaluation of pH and calcium ion diffusion from calcium hydroxide pastes and MTA / Evaluación del pH y la difusión de iones calciode pastas de hidróxido de calcio y MTA

The aim of this ex vivo study was to evaluate changes in pH andcalcium ion diffusion through root dentin from calcium hydroxide(Ca (OH)2) and mineral trioxide aggregate (MTA) pastes at 7,30 and 60 days; and the relationship between pH and iondiffusion. Thirty­two human premolars were used. Crowns weresectioned and root canals instrumented and filled in with thefollowing preparations: 1) Ca(OH)2 + distilled water (n=7); 2)Ca(OH)2 + 0.1% chlorhexidine gluconate (n=7); 3) MTA +distilled water (n=7); 4) MTA + 0.1% chlorhexidine gluconate(CHX) (n=7); 5) distilled water (n=2) (control); 6) 0.1%chlorhexidine gluconate (n=2) (control). The apex and coronaryopening were sealed with IRM. Roots were placed in Eppendorftubes with 1 ml distilled water at 37°C and 100% humidity. Atbaseline, 7, 30 and 60 days, pH was measured with pH meter,and calcium ion content in the solution was analyzed by atomicabsorption spectrophotometry. The data were statisticallyanalyzed using ANOVA, simple linear regression analysis andPearson’s correlation test. The highest pH values were achievedwith calcium hydroxide pastes at 60 days (p ≤ 0.05). Calciumions were released in all groups. The calcium hydroxide pastewith distilled water at 60 days had the highest calcium ion value(p ≤ 0.01). There was a positive correlation between calcium andpH values.

El objetivo de este estudio ex vivo fue evaluar los cambios en elpH y la difusión a través de la dentina radicular de iones calcioa partir de pastas de hidróxido de calcio (Ca (OH)2) y trióxidomineral agregado (MTA), durante 7, 30 y 60 días; y la relaciónentre el pH y la difusión de iones. Se utilizaron 32 premolareshumanos. Las coronas fueron seccionadas, los conductos radicu ­lares fueron instrumentados y obturados con las siguientespreparaciones: 1) Ca (OH)2 + agua destilada (n = 7); 2)Ca (OH)2 + gluconato de clorhexidina (CHX) al 0,1% (n = 7);3) MTA + agua destilada (n = 7); 4) MTA + gluconato declorhexidina al 0,1% (n = 7); 5) agua destilada (n = 2) (control);6) gluconato de clorhexidina al 0,1% (n = 2) (control). El ápicey la apertura coronaria se sellaron con IRM. Las raíces secolocaron en tubos Eppendorf con 1 ml de agua destilada a37 °C y 100% de humedad. Se midió el pH inicial y a los 7, 30 y60 días, con pHmetro, y se analizó el contenido de iones calcioen la solución por espectrofotometría de absorción atómica. Losdatos fueron analizados estadísticamente con ANOVA, análisisde regresión lineal y correlación de Pearson. Los valores de pHmás altos se obtuvieron con las pastas de hidróxido de calcio alos 60 días (p ≤ 0,05). Todos los grupos mostraron liberación deiones calcio. La pasta de hidróxido de calcio con agua destiladamostró el valor más alto de iones calcio a los 60 días (p ≤ 0,01).Hubo una correlación positiva entre los valores de pH y calcio.

Evaluation of the physicochemical properties of silicone- and epoxy resin-based root canal sealers

Abstract To assess the physicochemical properties of AH Plus, GuttaFlow 2, GuttaFlow BioSeal, and MM Seal, five samples of each root canal sealer were evaluated to determine their setting time (ST), dimensional change (DC), solubility (SL), flow (FL), and radiopacity (RD) according to American National Standards Institute/American Dental Association (ANSI/ADA) Specification 57. The distilled and deionized water obtained from the SL test were subjected to atomic absorption spectrometry to observe the presence of Ca2+, K+, and Na+ ions. Statistical analysis was performed by using one-way ANOVA and Tukey-Kramer tests (p < 0.05). The following results were obtained: ST (min) (AH Plus 463.6 ± 13.22; GuttaFlow 2 24.35 ± 2.78; GuttaFlow Bioseal 17.4 ± 0.55; MM Seal 47.60 ± 4.39), DC (%) (AH Plus 0.06 ± 0.12; GuttaFlow 2 −26.06 ± 1.24; GuttaFlow Bioseal 2.10 ± 1.47; MM Seal 8.47 ± 2.41), SL (%) (AH Plus 0.41 ± 0.21; GuttaFlow 2 5.13 ± 4.11; GuttaFlow Bioseal 3.03 ± 1.05; MM Seal 0.94 ± 0.17), FL (mm) (AH Plus 36.42 ± 0.40; GuttaFlow 2 36.44 ± 0.05; GuttaFlow Bioseal 35.4 ± 0.03; MM Seal 52.75 ± 0.60), and RD (mmAl) (AH Plus 7.52 ± 1.59; GuttaFlow 2 6.85 ± 0.14; GuttaFlow Bioseal 7.02 ± 0.18; MM Seal 3.32 ± 0.90). ST, DC, SL, FL, and RD showed statistical differences among the root canal sealers (p < 0.05). As AH Plus showed the lowest DC and SL values (p < 0.05), the findings indicate that this sample is the only sealer conforming to ANSI/ADA standards.

Seasonal study of concentration of heavy metals in waters from lower São Francisco River basin, Brazil / Estudo sazonal das concentrações de metais pesados em águas da bacia do submédio rio São Francisco, Brasil

Abstract In this study we determined the concentration of metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in the water lower São Francisco River basin, to evaluate the influence of urbanization and industrialization on environmental changes in the water resource. All samples were analyzed using the IUPAC adapted method and processed in an atomic absorption spectrophotometer. The sampling stations located near the industrial areas were influenced by industrialization because they presented higher concentrations of Cd, Cr, Ni and Cu. The other sampled locations showed changes with regard the trace elements probably originating in the soil, like Fe, Zn and Pb. There was a gradual increase in the concentrations of metals, in general, in the period of highest rainfall of the hydrographic network. Overall, except for Zn and Mn, the trace elements exceeded the maximum allowed value established by national legislation (CONAMA). Lower São Francisco River basin has suffered interference from urbanization and industrialization, so awareness programs should be developed so as to control and lessen future problems.

Resumo Neste trabalho foi determinada a concentração dos metais (Cd, Cr, Cu, Fe, Mn, Ni, Pb e Zn) na água do submédio Rio São Francisco para avaliar a influência da urbanização e da industrialização nas modificações ambientais do recurso hídrico. Todas as amostras foram analisadas usando o método IUPAC adaptado e processados em um espectrofotômetro de absorção atômica. As estações de amostragem localizadas próximas às áreas industriais sofreram influência da industrialização por apresentarem concentrações mais elevadas de Cd, Cr, Ni e Cu. Os demais locais amostrados apresentaram modificações com relação aos elementos traços de provável origem sedimentar como Fe, Zn e Pb. Houve aumento gradativo nas concentrações dos metais, de forma geral, no período de maior pluviosidade da rede hidrográfica. Em geral, com exceção do Zn e Mn, os elementos traços ultrapassaram o valor máximo permitido, estabelecido pela legislação nacional (CONAMA). O submédio Rio São Francisco tem sofrido interferência da urbanização e industrialização, por isso, é preciso que, programas de conscientização sejam estabelecidos, para controlar e amenizar problemas futuros.

Brachiopods, sipunculans, enteropneusts and metals from two estuarine tidal flats, Pacific, Costa Rica / Braquiópodos, sipuncúlidos, enteropneustos y metales en dos planicies estuarinas de marea, Pacífico, Costa Rica

Abstract:Reports on the abundances and on metal concentrations in intertidal estuarine invertebrates from the Eastern Tropical Pacific are rare. Thus, the objectives of this report are to make accessible data on the abundances (1984-1987, 49 dates; 2013, 12 dates) of sipunculans, brachiopods and hemichordates from a sand-mud flat; and on trace metals (1996, 2000) and abundances (2015, 3 dates) of sipunculans and brachiopods at a sand flat in the Gulf of Nicoya estuary (10o N-85o W). Cores (17.7 cm2) were collected at the sand-mud flat, and quadrats (0.2 m2) at the sand flat. The flats contrasted in their sand (65 % vs 90 %) and silt+clay (31.5 % vs 5.6 %) contents. At the sand-mud flat (1984-87: 1.83 m2) the sipunculans were represented by 13 individuals, the brachiopods by 129 and the acorn worms by 185, with estimated maximum densities of: 5.7, 29, and 40 ind./m2, respectively. Trace metal (Fe, Mn, Ni, Cr, Cd, Zn, and Pb) analysis (Atomic Absorption Spectrometry) were conducted in specimens of Sipunculus nudus (Sipuncula) and Glottidia audebarti (Brachiopoda). Maximum mean concentrations in S. nudus were: For non-depurated worms, Fe (16.0 mg/g dw) > Mn (165 µg/g dw) > Zn (81 µg/g dw) > Cu (26 µg/g dw) > Cr (11 µg/g dw) > Ni (10.4 µg/g dw) > Pb (9.3 µg/g dw) > Cd (1.2 µg/g dw). For 72 hour depurated worms: Fe (5.0 mg/g dw) > Mn (61 µg/g dw) > Zn (39 µg/g dw) > Cu (24 µg/g dw) > Ni (8.4 µg/g dw) > Pb (2.7 µg/g dw) > Cd (0.62 µg/g dw). For G. audebarti: Fe (1.6 mg/g dw-soft parts) > Zn (123.5 µg/g dw-soft parts) > Cu (31.4 µg/g dw-pedicles) > Pb (21.0 µg/g dw-shells) > Cd (5.2 µg/g dw-soft parts) > Cr (4.7 µg/g dw-shells). For sediments; Fe (46 mg/g dw) > Mn (41.3 µg/g dw) > Zn (63 µg/g dw) > Cu (36.2 µg/g dw) > Cr (31.5 µg/g dw) > Pb (21.1 µg/g dw) > Ni (16.1 µg/g dw) > Cd (1.1 µg/g dw). These concentrations were expected for a nonindustrialized estuary. At the sand flat (Area sampled: 10.6 m2 ) 76 individuals of G. audebarti, 112 of G. albida, and 366 of S. nudus were collected in 2015, with estimated maximum densities of: 7.1, 10.5, and 31 ind./m2, respectively. Densities of G. audebarti and G. albida were relatively low, while those of S. nudus were relatively high when compared with other reports. The shell lenght of G. audebarti ranged from 9.0 mm to 38.0 mm and from 6.0 mm to 29.0 mm for G. albida. These ranges were within those found for these lingulides elsewhere. The mean length of S. nudus was 41 mm and the maximum weight was 1.6 g, which are small. No brachiopods were found at the sand-mud flat in 2013, nor enteropneusts at the sand flat in 2015. G. audebarti had a relatively stable presence, while G. albida almost vanished from the samples at the end of 2015. The spatial distributions of the three invertebrates were found aggregated at both intertidal flats. Strong ENSO warming events during 1983 and 2015, and red tides in 1985 may have influenced the abundances. Rev. Biol. Trop. 64 (3): 1311-1331. Epub 2016 September 01.

ResumenSon raros los reportes sobre las abundancias y concentraciones de metales en invertebrados estuarinos de la zona de entre-mareas del Pacífico Este Tropical. Los objetivos de este informe son el hacer accesibles datos sobre las abundancias (1984-1987, 49 fechas; 2013, 12 fechas) de sipuncúlidos, braquiópodos y hemicordados en una planicie arenoso-fangosa y sobre metales traza (1996, 2000) y abundancias (2015, 3 fechas) de sipuncúlidos y braquiópodos en una planicie arenosa en el estuario del Golfo de Nicoya (10o N-85o W). Barrenos (17.7 cm2) fueron recolectados en la planicie arenoso-fangosa y cuadrantes (0.2 m2) en la arenosa. Las planicies contrastaron en sus contenidos de arena (65 % vs 90 %) y de limo + arcilla (31.5 % vs 5.6 %). En la planicie arenoso-fangosa (1984-87: 1.83 m2) los sipuncúlidos estuvieron representados por 13 individuos, los braquiópodos por 129 y los hemicordados enteropneustos por 185, con densidades estimadas de: 5.7, 29, y 40 ind. /m2, respectivamente. Análisis de metales traza (Fe, Mn, Ni, Cr, Cd, Zn, y Pb) por Espectrometría de Absorción Atómica (AAS) fueron hechos en especímenes de Sipunculus nudus (Sipuncula) y Glottidia audebarti (Brachiopoda). Concentraciones máximas promedio en S. nudus fueron: para gusanos no-depurados, Fe (16.0 mg/g dw) > Mn (165 µg/g dw) > Zn (81 µg/g dw) > Cu (26 µg/g dw) > Cr (11 µg/g dw) > Ni (10.4 µg/g dw) > Pb (9.3 µg/g dw) > Cd (1.2 µg/g dw). Para gusanos depurados por 72 horas: Fe (5.0 mg/g dw) > Mn (61 µg/g dw) > Zn (39 µg/g dw) > Cu (24 µg/g dw) > Ni (8.4 µg/g dw) > Pb (2.7 µg/g dw) > Cd (0.62 µg/g dw). Para G. audebarti: Fe (1.6 mg/g dw-partes suaves) > Zn (123.5 µg/g dw-partes suaves) > Cu (31.4 µg/g dwpedículos) > Pb (21.0 µg/g dw-conchas) > Cd (5.2 µg/g dw-partes suaves) > Cr (4.7 µg/g dw-conchas). Para sedimentos; Fe (46 mg/g dw) > Mn (41.3 µg/g dw) > Zn (63 µg/g dw) > Cu (36.2 µg/g dw) > Cr (31.5 µg/g dw) > Pb (21.1 µg/g dw) > Ni (16.1 µg/g dw) > Cd (1.1 µg/g dw). Estas concentraciones fueron esperables para un estuario no industrializado. En la planicie arenosa (Area muestreada: 10.6 m2) 76 individuos de G. audebarti, 112 de G. albida y 366 de S. nudus fueron recolectados en el 2015, con densidades estimadas de: 7.1, 10.5, y 31 ind. /m2, respectivamente. Densidades de G. audebarti y G. albida fueron relativamente bajas, mientras que las de S. nudus fueron relativamente altas cuando se les comparó con otros reportes. La longitud de la concha de G. audebarti varió entre 9.0 mm y 38.0 mm y entre 6.0 mm a 29.0 mm la de G. albida. Estos ámbitos estuvieron dentro de los encontrados para estos lingúlidos en otros sitios. La longitud promedio de S. nudus fue 41 mm y el peso máximo fue de 1.6 g que son pequeños. En la planicie arenoso-fangosa no se encontró braquiópodos en el 2013, ni enteropneustos en la planicie arenosa en el 2015. G. audebarti tuvo una presencia relativamente estable, mientras que G. albida casi desapareció de las muestras al final del 2015. La distribución espacial de las tres especies fue de tipo agregado en ambas planicies. Fuertes eventos ENSO durante 1983 y 2015, así como mareas rojas en 1985, pueden haber influenciado las abundancias.

Evaluación genotóxica de sedimentos de la cuenca Matanza-Riachuelo bajo la influence de distintos usos del suelo / Genotoxic evaluation of sludge from Matanza-Riachuelo basin under the influence of different uses of land

El Río Matanza-Riachuelo y sus afluentes atraviesan zonas con diferente grado de contaminación generada por las actividades agrícola-ganaderas, urbana e industrial. Los contaminantes que llegan al agua y son depositados en los sedimentos pueden ser liberados nuevamente al agua generando efectos tóxicos y/o genotóxicos sobre los organismos acuáticos. El objetivo de este trabajo fue analizar la genotoxicidad de muestras de sedimentos de la cuenca Matanza-Riachuelo obtenidas de zonas con diferentes usos del suelo. Se seleccionaron cuatro sitios de muestreo. Se utilizaron 2 métodos de extracción de contaminantes (agitación y sonicación), 2 solventes orgánicos (metanol y diclorometano) y 2 solventes inorgánicos (agua y solución ácida), obteniéndose un total de 5 extractos para cada muestra. Se realizaron mediciones de metales pesados e hidrocarburos aromáticos policíclicos (HAPs) mediante espectrofotometría de absorción atómica y CG/MS, respectivamente. La genotoxicidad se evaluó mediante el test de Ames con 2 cepas de Salmonella typhimurium (TA98 y TA100), con y sin fracción microsomal S9, y el test de Allium cepa. De los cuatro sitios estudiados, los sedimentos del Riachuelo mostraron mayores concentraciones de metales pesados y HAPs. Para el test de Ames, sólo los extractos obtenidos en diclorometano resultaron genotóxicos para la TA100 +S9 mix. Tanto los extractos inorgánicos como los orgánicos fueron citotóxicos y genotóxicos para A. cepa. Se observó una correlación negativa entre algunos compuestos HAPs y la frecuencia de micronúcleos, indicando la presencia de efectos antagónicos con otros compuestos genotóxicos. Los extractos con mayor efecto tóxico y genotóxico fueron los obtenidos con diclorometano y solución ácida. Este estudio mostró que los contaminantes orgánicos e inorgánicos extraídos de muestras de sedimento de la Cuenca Matanza-Riachuelo, con diferente grado de impacto, presentan un potencial riesgo tóxico y genotóxico para el ecosistema acuático.

The Matanza-Riachuelo River and its tributaries traverse areas with different degrees of contamination due to farming, urban and industrial activities. The pollutants entering the water are deposited in sediments, and can be released back into the water producing toxic and/or genotoxic effects on aquatic organisms. The aim of this study was to analyze the genotoxicity of sediment samples from the Matanza-Riachuelo Basin with different land uses. Four sampling sites according to the characteristics of land use were selected. Two methods of extraction (stirring and sonication), two organic solvents (methanol and dichloromethane) and two inorganic solvents (water and acid solution) were used, yielding a total of 5 extracts for each sample. Measurements of heavy metals and polycyclic aromatic hydrocarbons (PAHs) by atomic absorption spectrophotometry and GC/MS, respectively were performed. Genotoxicity was assessed using the Ames test with 2 strains of Salmonella typhimurium (TA98 and TA100) with and without S9 microsomal fraction, and the Allium cepa test. Taking into account the four sites, sediments from Riachuelo showed higher concentrations of heavy metals and PAHs. Only the dichloromethane extracts were genotoxic to the Ames test using the TA100 strain +S9 the mix. Both organic and inorganic extracts were cytotoxic and genotoxic to A. cepa. A negative correlation between some PAHs compounds and micronucleus frequency were observed, indicating the presence of antagonistic effects with other genotoxic compounds in samples. The extracts with high toxic and genotoxic effects were obtained with dichloromethane and acid solution. This study showed that organic and inorganic contaminants extracted from sediment samples from the Matanza-Riachuelo Basin, with varying degrees of impact, have potential toxic and genotoxic risk to the aquatic ecosystem.