Prácticas de análisis estadístico de datos geoquímicos con el programa R

Son muchas las materias de carácter geológico como geoquímica, prospección geoquímica, petrología, recursos minerales, mineralogía ambiental, etc., donde el análisis estadístico de datos geoquímicos es una herramienta básica y necesaria. La toma de datos en el campo o en el laboratorio, el análisis, representación e interpretación de datos que proceden de un laboratorio analítico son tareas comunes en la toma de decisiones o explicación de procesos geoquímicos y petrogenéticos, detección de anomalías geoquímicas, procedencia de aguas, etc. En dichos estudios se suelen realizar análisis químicos de suelos, sedimentos y/o aguas, que incluyen más de una docena de elementos (variables) y varios puntos de muestreo (casos).Este trabajo está enmarcado dentro de la Red de Investigación en Docencia Universitaria (2899) y el Grupo de Innovación Tecnológico-Educativa (GITE-11013-UA: Petrología y Geoquímica) de la Universidad de Alicante

Phytochemical analysis and biological potential of Argentinian plant essential oils and extracts

Our aim is to characterize the chemical composition, antimicrobial, antioxidant and anti-inflammatory potentials of the essential oils (EOs) and ethanolic extracts (EEs) of five northwest native plants in Argentina. The EOs and EEs were obtained from Lippia turbinata, Clinopodium gilliesii, Lippia integrifolia, Zuccagnia punctata, and Senecio subulatus var. salsus. EOs and EEs phytochemical composition were determined by GC-MS analysis and spectrophotometric methods. Antibacterial activity was assessed against Gram-negative and -positive pathogenic bacteria. Antioxidant activity was evaluated by DPPH radical scavenging assay and anti-inflammatory potential was determined by cyclooxygenase (COX-2) inhibition assay. EOs and EEs of all assayed plant species showed weak antibacterial effect. The EEs had stronger scavenging activity than the EOs. The best results were achieved for Z. punctata EE followed by L. turbinata and C. gilliesii EEs. The EOs exhibited greater inhibitory activity towards the COX-2 than EEs. C. gilliesii and L. integrifolia EOs showed the highest COX-2 inhibitory activity. These results would indicate that antioxidant activity is concentrated in the non-volatile fraction of the plants whether the anti-inflammatory activity is in the volatile one. This work contributes to knowledge of biological properties of plants from our region and could help to discover compounds with potential therapeutic uses.Fil: Barbieri, Natalia Paola del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Chilecito. Departamento de Ciencias Basicas y Tecnologicas; Argentina. Instituto de Ambiente de Montaña y Regiones Áridas; ArgentinaFil: Gilabert Valero, José Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Benavente, Alba María del Valle. Universidad Nacional de Chilecito. Departamento de Ciencias Basicas y Tecnologicas; Argentina. Instituto de Ambiente de Montaña y Regiones Áridas; Argentin

Characterization of glycoproteins by capillary electrophoresis electrospray mass spectrometry (CE-ESI-MS). Applications to diagnosis in biomedicine

Glycosylation is the most common posttranslational modification in proteins and the carbohydrates participate in many biological processes. The number and type of glycoforms for a certain glycoprotein may change as a consequence of pathological processes. In our work a method for the separation of transferrin sialoforms has been developed, that permits the diagnostic of Congenital Disorders of Glycosylation (CDG) using a polybrene-dextran sulphate coating and CE-ESI-TOF methodologies. In order to improve the sensitivity the use of solid-phase extraction coupled on-line to CE-ESI-MS is studied and the SPE-CE-ESI-MS developed methods are applied for the characterization of rHuEPO glycoforms. The achieved separation and the high mass-resolving power of flight (TOF) mass detection allows to establish the most probable rHuEPO glycoforms

Determination of acidity constants and prediction of electrophoretic separation of amyloid beta peptides

In this paper we describe a strategy to estimate by CE the acidity constants (pKa) of complex polyprotic peptides from their building peptide fragments. CE has been used for the determination of the pKas of five short polyprotic peptides that cover all the sequence of amyloid beta (Aβ) peptides 1-40 and 1-42 (Aβ fragments 1-15, 10-20, 20-29, 25-35 and 33-42). First, the electrophoretic mobility (me) was measured as a function of pH of the background electrolyte (BGE) in the pH range 2-12 (bare fused silica capillary, I=25mM and T=25ºC). Second, the mes were fitted to equations modelling the ionisable behaviour of the different fragments as a function of pH to determine their pKas. The accuracy of the pKas was demonstrated predicting the electrophoretic behaviour of the studied fragments using the classical semiempirical relationships between me and peptide charge-to-mass ratio (me vs. q/Mr1/2, classical polymer model, q=charge and Mr=relative molecular mass). Separation selectivity in a mixture of the fragments as a function of pH was evaluated, taking into account the influence of the EOF at each pH value, and a method for the simple and rapid simulation of the electropherograms at the optimum separation pH was described. Finally, the pKas of the fragments were used to estimate the pKas of the Aβ peptides 1-40 and 1-42 (tC and D 3.1, E 4.6 and Y 10.8 for acidic amino acids and tN-D 8.6, H 6.0, K 10.6 and R 12.5 for basic amino acids), which were used to predict their behaviour and simulate their electropherograms with excellent results. However, as expected due to the very small differences on q/Mr1/2 values, separation resolution of their mixtures was poor over the whole pH range. The use of poly(vinyl alcohol) (PVA) coated capillaries allowed reducing the electroosmotic flow (EOF) and a slight improvement of resolution

Accurate determination of the milk protein allergen β-lactoglobulin by on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry

An on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry (AA-SPE-CE-MS) method was developed to purify, preconcentrate, separate, and characterize the milk allergenic protein β-lactoglobulin (β-LG) in food samples. The sorbent to pack into the SPE microcartidges was prepared by immobilizing an aptamer against β-LG onto magnetic bead particles. After optimizing the SPE-CE-MS method, the sample (ca. 75 µL) was loaded in separation background electrolyte (BGE, 2 M acetic acid pH 2.2), while a solution of 100 mM NH4OH (pH 11.2) (ca. 100 nL) was used for the protein elution. The linearity of the method ranged between 0.1 and 20 µg·mL-1 and the limit of detection (LOD) was 0.05 µg·mL-1, which was 200 times lower than by CE-MS. The method was repeatable in terms of relative standard deviation (RSD) for migration times and peak areas (< 0.5 % and 2.4 %, respectively) and microcartridge lifetime was more than 25 analyses. The applicability of the method for the determination of low levels of β-LG was shown by analyzing milk-free foods (i.e. a 100 % cocoa dark chocolate, a hypoallergenic formula for infants, and a dairy-free white bread) and milk-containing white breads. Results were satisfactory in all cases, thus demonstrating the great potential of the developed method for accurate food safety and quality control

Determination of a lectin protein allergen in food by on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry

An aptamer affinity sorbent was prepared for clean-up, preconcentration, separation and characterization of a food allergen protein by on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry (AA-SPE-CE-MS). SPE microcartridges were packed with a sorbent based on magnetic bead particles modified with an aptamer against the target lectin protein concanavalin A (Con A). After optimization of several parameters of the SPE-CE-MS method, the sample (ca. 30 µL) was loaded in separation background electrolyte (BGE, 2 M acetic acid pH 2.2), while the retained protein was eluted with 100 mM NH4OH (pH 11.2) (ca. 100 nL). The developed method was linear between 0.5 and 20 mg·L-1 and the limit of detection (LOD) was 0.25 mg·L-1, which was 100 times lower than by CE-MS. The repeatability of the method was satisfactory, with relative standard deviations (RSD) for migration times and peak areas below 1.9 and 8.1%, respectively. In addition, the microcartridges could be reused more than 25 analyses without significant loss of extraction efficiency. Finally, the applicability and versatility of the developed method were demonstrated by analyzing low levels of Con A in different food matrices (i.e. white beans, as well as chickpea, lentils, and wheat flours), leading to satisfactory results, with recoveries between 87 and 115%

Groundwater-Surface Water Interactions in “La Charca de Suárez” Wetlands, Spain

La Charca de Suárez (LCS) is a Protected Nature Reserve encompassing 4 lagoons located 300 m from the Mediterranean coast in southern Spain. LCS is a highly anthropized area, and its conservation is closely linked to the human use of water resources in its surroundings and within the reserve. Different methodologies were applied to determine the hydrodynamics of the lagoons and their connection to the Motril-Salobreña aquifer. Fieldwork was carried out to estimate the water balance of the lagoon complex, the groundwater flow directions, the lagoons-aquifer exchange flow and the hydrochemical characteristics of the water. The study focussed on the changes that take place during dry-wet periods that were detected in a 7-month period when measurements were collected. The lagoons were connected to the aquifer with a flow-through functioning under normal conditions. However, the predominant inlet to the system was the anthropic supply of surface water which fed one of the lagoons and produced changes in its flow pattern. Sea wave storms also altered the hydrodynamic of the lagoon complex and manifested a future threat to the conservation status of the wetland according to predicted climate change scenarios. This research presents the first study on this wetland and reveals the complex hydrological functioning of the system with high spatially and temporally variability controlled by climate conditions and human activity, setting a corner stone for future studies.This study was supported by grant CGL2016-77503-R from the Ministry of Economy and Competitiveness (MINECO), cofounded by the European Regional Development Fund (ERDF) of the European Union (EU), and the RNM-369 research group of the regional government of Andalusia

Hereditary primary lateral sclerosis and progressive nonfluent aphasia

Objective: to report a kindred with an association between hereditary primary lateral sclerosis (PLS) and progressive nonfluent aphasia. Patients and methods: six members from a kindred with 15 affected individuals spanning three generations, suffered from spasticity without muscle atrophy or fasciculation, starting in the lower limbs and spreading to the upper limbs and bulbar musculature, followed by effortful speech, nonfluent language and dementia, in 5 deceased members. Disease onset was during the sixth decade of life, or later. Cerebellar ataxia was the inaugural manifestation in two patients, and parkinsonism, in another. Results: neuropathological examination in two patients demonstrated degeneration of lateral corticospinal tracts in the spinal cord, without loss of spinal, brainstem, or cerebral motor neurons. Greater loss of corticospinal fibers at sacral and lumbar, rather than at cervical or medullary levels was demonstrated, supporting a central axonal dying-back pathogenic mechanism. Marked reduction of myelin and nerve fibers in the frontal lobes was also present. Argyrophilic grain disease and primary age-related tauopathy were found in one case each, and considered incidental findings. Genetic testing, including exome sequencing aimed at PLS, ataxia, hereditary spastic paraplegia, and frontotemporal lobe dementia, triplet-repeated primed polymerase chain reaction aimed at dominant spinocerebellar ataxias, and massive sequencing of the human genome, yielded negative results. Conclusion: a central distal axonopathy affecting the corticospinal tract, exerted a pathogenic role in the dominantly inherited PLS-progressive nonfluent aphasia association, described herein. Further molecular studies are needed to identify the causative mutation in this disease

Heterogeneity of the Vega de Granada aquifer in the Granada urban area (Spain)

Datos hidrodinámicos obtenidos en 5 sondeos situados en la ciudad de Granada y en su área periurbana corroboran la heteroge-neidad horizontal y vertical en la conductividad hidráulica del acuí-fero aluvial de la Vega de Granada (AVG) en su extremo oriental. También ponen de manifiesto la existencia de un nivel colgado bajo uno de los puntos estudiados (FC) y caracterizan su vaciado desde 2001. Se confirma la respuesta hidrodinámica más efectiva frente a la recarga en el extremo SE del sector estudiado. Se propone un mo-delo conceptual que integra nuestros resultados en el contexto de la evolución piezométrica ligada al incremento de bombeos en la mitad este del AVG desde aproximadamente 1970.Hydrodynamic data in 5 wells located in the city of Granada and in its peri-urban area asses the horizontal and vertical heterogeneity in the hydraulic conductivity of the Vega de Granada alluvial aqui-fer (AVG) at its eastern part. They also indicate the existence of a perched level in one of the studied points (FC) and characterize its lowering since 2001. It is confirmed that the hydrodynamic response to recharge is more effective in the SE of the studied sector. A con-ceptual model is proposed that integrates our results in the context of the piezometric evolution linked to the increase in pumping in the eastern half of the AVG since approximately 197