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Alpha-synuclein (αsyn) is an intrinsically disordered protein that aggregates in the brain in several neurodegenerative diseases collectively called synucleinopathies. Phosphorylation of αsyn at serine 129 (PSER129) was considered rare in the healthy human brain but is enriched in pathological αsyn aggregates and is used as a specific marker for disease inclusions. However, recent observations challenge this assumption by demonstrating that PSER129 results from neuronal activity and can be readily detected in the non-diseased mammalian brain. Here, we investigated experimental conditions under which two distinct PSER129 pools, namely endogenous-PSER129 and aggregated-PSER129, could be detected and differentiated in the mammalian brain. Results showed that in the wild-type (WT) mouse brain, perfusion fixation conditions greatly influenced the detection of endogenous-PSER129, with endogenous-PSER129 being nearly undetectable after delayed perfusion fixation (30-min and 1-h postmortem interval). Exposure to anesthetics (e.g., Ketamine or xylazine) before perfusion did not significantly influence endogenous-PSER129 detection or levels. In situ, non-specific phosphatase calf alkaline phosphatase (CIAP) selectively dephosphorylated endogenous-PSER129 while αsyn preformed fibril (PFF)-seeded aggregates and genuine disease aggregates (Lewy pathology and Papp-Lantos bodies in Parkinson's disease and multiple systems atrophy brain, respectively) were resistant to CIAP-mediated dephosphorylation. The phosphatase resistance of aggregates was abolished by sample denaturation, and CIAP-resistant PSER129 was closely associated with proteinase K (PK)-resistant αsyn (i.e., a marker of aggregation). CIAP pretreatment allowed for highly specific detection of seeded αsyn aggregates in a mouse model that accumulates non-aggregated-PSER129. We conclude that αsyn aggregates are impervious to phosphatases, and CIAP pretreatment increases detection specificity for aggregated-PSER129, particularly in well-preserved biological samples (e.g., perfusion fixed or flash-frozen mammalian tissues) where there is a high probability of interference from endogenous-PSER129. Our findings have important implications for the mechanism of PSER129-accumulation in the synucleinopathy brain and provide a simple experimental method to differentiate endogenous-from aggregated PSER129.

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Alpha-synuclein (αsyn) is an intrinsically disordered protein that aggregates in the brain in several neurodegenerative diseases collectively called synucleinopathies. Phosphorylation of αsyn at serine 129 (PSER129) was considered rare in the healthy human brain but is enriched in pathological αsyn aggregates and is used as a specific marker for disease inclusions. However, recent observations challenge this assumption by demonstrating that PSER129 results from neuronal activity and can be readily detected in the non-diseased mammalian brain. Here, we investigated experimental conditions under which two distinct PSER129 pools, namely endogenous-PSER129 and aggregated-PSER129, could be detected and differentiated in the mammalian brain. Results showed that in the wild-type (WT) mouse brain, perfusion fixation conditions greatly influenced the detection of endogenous-PSER129, with endogenous-PSER129 being nearly undetectable after delayed perfusion fixation (30-minute and 1-hour postmortem interval). Exposure to anesthetics (e.g., Ketamine or xylazine) before perfusion did not significantly influence endogenous-PSER129 detection or levels. In situ, non-specific phosphatase calf alkaline phosphatase (CIAP) selectively dephosphorylated endogenous-PSER129 while αsyn preformed fibril (PFF)-seeded aggregates and genuine disease aggregates (Lewy pathology and Papp-Lantos bodies in Parkinson's disease and multiple systems atrophy brain, respectively) were resistant to CIAP-mediated dephosphorylation. The phosphatase resistance of aggregates was abolished by sample denaturation, and CIAP-resistant PSER129 was closely associated with proteinase K (PK)-resistant αsyn (i.e., a marker of aggregation). CIAP pretreatment allowed for highly specific detection of seeded αsyn aggregates in a mouse model that accumulates non-aggregated-PSER129. We conclude that αsyn aggregates are impervious to phosphatases, and CIAP pretreatment increases detection specificity for aggregated-PSER129, particularly in well-preserved biological samples (e.g., perfusion fixed or flash-frozen mammalian tissues) where there is a high probability of interference from endogenous-PSER129. Our findings have important implications for the mechanism of PSER129-accumulation in the synucleinopathy brain and provide a simple experimental method to differentiate endogenous-from aggregated PSER129.

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INTRODUCTION: Subjective memory complaints (SMC) are considered predictor of cognitive impairment, but are also associated with other factors; social and lifestyle have been the least studied. AIM: To evaluate SMC and their association with epidemiological, health, social and lifestyle variables. SUBJECTS AND METHODS: Cross-sectional epidemiological study of the randomly selected population of Madrid. Telephone interview. TARGET POPULATION: 1,775 over 55 years of age. We asked about QSM, social, economic, health and lifestyle aspects. The Goldberg General Health Questionnaire (GHQ) and the COOP-Wonca Quality of Life Questionnaire were administered. RESULTS: We found statistically significant association of SMC with age, temporal orientation, all variables related to mental health (depression), anxiety, sleep, mental health/GHQ, and quality of life. Association was found with all pain variables and with loneliness. There was no association with specific diseases, except chronic allergy and those linked to pain. The predictors of the SMC were temporal orientation, multimorbidity, mental health/GHQ, anxiety, pain and feeling lonely. CONCLUSIONS: SMC is a multi-caused symptom. They are associated with lower memory performance, but also with variables related to health, social aspects and lifestyle. When faced with a patient with SMC, which may be due to cognitive impairment because of Alzheimer's disease, these associations should be taken into account to assess this risk and know when follow-up is most needed.

TITLE: Quejas de memoria: salud mental, enfermedades, dolor y soledad. Estudio poblacional en la ciudad de Madrid.Introducción. Las quejas subjetivas de memoria (QSM) se consideran predictoras del deterioro cognitivo, pero se asocian también a otros factores; los sociales y los hábitos de vida han sido los menos estudiados. Objetivo. Valorar las QSM y su asociación con variables epidemiológicas, de salud, sociales y hábitos de vida. Sujetos y métodos. Estudio epidemiológico trasversal de la población de Madrid elegida aleatoriamente según censo. Entrevista telefónica. Población diana: 1.775 mayores de 55 años. Se preguntó sobre QSM, aspectos sociales, económicos, de salud y hábitos de vida. Se administraron el cuestionario de salud general de Goldberg (GHQ) y el cuestionario de calidad de vida COOP-Wonca. Resultados. Encontramos asociación estadísticamente significativa de las QSM con la edad, la orientación temporal, todas las variables relacionadas con la salud mental (depresión), la ansiedad, el sueño, la salud mental/GHQ y la calidad de vida. Se halló asociación con todas las variables que miden el dolor y con sentir soledad. No hubo asociación con enfermedades específicas, excepto con la alergia crónica y las ligadas al dolor. Los predictores de las QSM fueron la orientación temporal, la multimorbilidad, la salud mental/GHQ, la ansiedad, el dolor y el sentir soledad. Conclusiones. Las QSM son un síntoma con múltiples causas. Se asocian a menor rendimiento de la memoria, pero también a variables relacionadas con la salud, los aspectos sociales y el tipo de vida. Ante un paciente con QSM, que pueden deberse al deterioro cognitivo por enfermedad de Alzheimer, deben considerarse estas asociaciones para valorar dicho riesgo y saber cuándo es más necesario un seguimiento.

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Itolizumab is a humanized anti-CD6 monoclonal antibody (mAb) that has previously shown encouraging results, in terms of safety and positive clinical effects, in a 6-week monotherapy clinical trial conducted in rheumatoid arthritis (RA) patients. The current Phase I study evaluated the safety and clinical response for a longer treatment of 12 itolizumab intravenous doses in subjects with active RA despite previous disease-modifying anti-rheumatic drug (DMARD) therapy. Twenty-one subjects were enrolled into four dosage groups (0·1, 0·2, 0·4 and 0·8 mg/kg). Efficacy end-points including American College of Rheumatology (ACR)20, ACR50 and ACR70 response rates and disease activity score in 28 joints (DAS28) were monitored at baseline and at specific time-points during a 10-week follow-up period. Itolizumab was well tolerated up to the highest tested dose. No related serious adverse events were reported and most adverse events were mild. Remarkably, itolizumab treatment did not produce lymphopenia and, therefore, was not associated with infections. All patients achieved a clinical response (ACR20) at least once during the study. Eleven subjects (55%) achieved at least a 20% improvement in ACR just 1 week after the first itolizumab administration. The clinical response was observed from the beginning of the treatment and was sustained during 24 weeks. The efficacy profile of this 12-week treatment was similar to that of the previous study (6-week treatment). These results reinforce the safety profile of itolizumab and provide further evidence on the clinical benefit from the use of this anti-CD6 mAb in RA patients.

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A fast (16min) procedure to assess the bioaccessible metallic fraction of Cd, Cr, Cu, Ni, Pb and Zn simultaneously extracted (SEM) from marine sediments plus an indirect approach to determine acid volatile sulfides (AVS) are presented. For the extraction process magnetic agitation was compared with ultrasonic stirring (using a bath and a probe), and several stirring times were assayed. The proposed SEM procedure uses an ultrasonic probe and 1mL of HCl. It dramatically minimizes the turnaround time and the residues. AVS were evaluated as the difference between the amounts of sulphur in the solid residue after the extraction and total sulphur in the original sample. These procedures are fast, easy to implement and cost-effective to assess the potential risk posed by metals in marine sediments. They were tested using several CRMs and applied to sediments from two Galician Rias (NW Spain); their SEM-AVS differences indicated no biological risk.

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Antecedentes: Los niveles adecuados de vitamina D y calcio en la infancia determinan el desarrollo adecuado de la masa ósea. En la actualidad se ha detectado déficit de vitamina D en determinadas poblaciones infantojuveniles, como en lactantes y adolescentes pero existe información insuficiente respecto al estado de la vitamina D en niños de otras edades. Objetivo: Determinar los niveles séricos de vitamina D en niñas prepuberales sanas de una ciudad del sur de Europa y estudiar el efecto de la exposición solar, la actividad física y la ingesta. Métodos: Se estudiaron 56 niñas caucasianas, sanas y prepúberes entre 7-10 años. Se recogieron datos sobre ingesta nutricional y actividad física. Las muestras de sangre se obtuvieron en diciembre. Resultados: La ingesta de vitamina D fue significativamente menor a las recomendaciones internacionales. Los niveles medios de calcidiol fueron de 40,07 ± 10,49 ng/ ml. Ninguna niña presentó un nivel inferior a 20 ng/ml; un 25% (14 niñas) tenían unos niveles entre 20-30 ng/ml, y un 75 % superiores a 30 ng/ml. No hemos encontrado diferencias en los niveles de vitamina D entre las niñas que realizaban actividad física, y las sedentarias. Conclusión: Los niveles de vitamina D en niñas prepúberes que viven al sur de España al inicio del invierno son adecuados. No obstante, se debe asegurar una ingesta adecuada de vitamina D, así como una exposición solar suficiente y realizar seguimiento en estas edades para evitar deficiencias (AU)

Background: Vitamin D and calcium play an important role in peak bone mass acquisition. Recent studies havesuggested that vitamin D deficiency in children is widespread, mainly during infancy and adolescent years. However, the vitamin D status at others ages is unsufficiently investigated. Objectives: To determine the vitamin D status in prepubertal, healthy South European girls, and to examine the relationship between serum vitamin D concentrations, sun exposure, physical activity and dietary intake. Methods: A cross-sectional observational study was conducted on 56 Caucasian; healthy and prepubertal girls aged 7-10 years. Dietary information, amount of sunlight exposure and activity were estimated. Blood samples were extracted in the first week of December. Results: Vitamin D intake was below the international recommended references. Mean serum vitamin D was 40.07 ± 10.49 ng/ml. No girl presented a level lower than 20 ng/ml; 25% had levels between 20-30 ng/ml and 75% above 30 ng/ml. We have not found differences in vitamin D levels from the girls who did sport and those who were sedentary. Conclusions: Vitamin D status is suitable for prepubertal girls living in the South of Spain at the beginning of winter. However, it is necessary to follow-up girls and check and adequate vitamin D intake, as well as sufficient sun exposure (AU)

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Avaliaram-se o átrio esquerdo (AE) utilizando-se o método bidimensional (2-B) (corte transverso) e a relação átrio esquerdo:aorta (AE:Ao), em um grupo de 40 cães adultos e sadios, entre um, cinco e sete anos de idade e com pesos corpóreos de 3,2kg a 38,3kg, e compararam-se esses valores aos do modo-M convencional. Observou-se diferença entre AE e Ao nos dois métodos e entre os seus respectivos índices. A correlação foi positiva alta entre peso e superfície corpórea e entre AE no modo 2-B (AEB) e AE no modo-M (AEM). Não se observou correlação entre os índices, nos dois métodos, com o peso e a superfície corpórea, isto é, os índices são independentes do peso ou da superfície corpórea. Concluiu-se que o AEB é maior do que o AEM, o índice médio para o AEB:AoB é de 1,379, e o intervalo de confiança de 1,337 a 1,422. O índice no método 2-B é, portanto, superior ao índice no modo-M.

The left atrium (LA) was evaluated through the bidimensional method (2-D) (short axis) and the relation left atrium:aorta (LA:Ao) in a group of 40 healthy adult dogs between 1.5 and 7 years of age and weights ranging from 3.2 to 38.3kg, and these values were compared to those in the conventional M-mode. Comparing the variable LA and Ao with the two methods and their respective indexes, significant statistical difference was observed (P<0,001), high positive correlation between the weight and LA-2D and LAM, between body surface and LA-2D and LAM. A difference between LA and Ao in both methods and these respective indicators were observed. The association was higly positive between weight and body surface area (BSA) and between M- mode LA (LAM) and 2-D mode LA (LA-2D). No correlation was observed between these indicators and weight and BSA, in both methods, so these indicators are weight and BSA-independent. Conclusions: LA-2D is bigger than LAM, the LA-2D:Ao-2D average index is 1,379 and the confidence interval is 1,337 to 1,422. The index in the 2-D method is, therefore, superior to the index in the M-mode.

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BACKGROUND: Vitamin D and calcium play an important role in peak bone mass acquisition. Recent studies have suggested that vitamin D deficiency in children is widespread, mainly during infancy and adolescent years. However, the vitamin D status at others ages is unsufficiently investigated. OBJECTIVES: To determine the vitamin D status in prepubertal, healthy South European girls, and to examine the relationship between serum vitamin D concentrations, sun exposure, physical activity and dietary intake. METHODS: A cross-sectional observational study was conducted on 56 Caucasian; healthy and prepubertal girls aged 7-10 years. Dietary information, amount of sunlight exposure and activity were estimated. Blood samples were extracted in the first week of December. RESULTS: Vitamin D intake was below the international recommended references. Mean serum vitamin D was 40.07 ± 10.49 ng/ml. No girl presented a level lower than 20 ng/ml; 25% had levels between 20-30 ng/ml and 75% above 30 ng/ml. We have not found differences in vitamin D levels from the girls who did sport and those who were sedentary. CONCLUSIONS: Vitamin D status is suitable for prepubertal girls living in the South of Spain at the beginning of winter. However, it is necessary to follow-up girls and check and adequate vitamin D intake, as well as sufficient sun exposure.

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BACKGROUND: In 2007, the Hospital Infantil Los Ángeles (HILA) in Colombia implemented a slightly-modified version of the WHO guidelines for the diagnosis and management of malnutrition during childhood. OBJECTIVE: To evaluate the efficacy of the WHO-HILA protocol in children hospitalized with severe, chronic marasmus and kwashiorkor malnutrition (MS-KWK) in 2007 and 2008. MATERIAL AND METHODS: In this descriptive retrospective study the records of 100 children hospitalized with MSKWK were initially evaluated. Of these, 30 fulfilled the inclusion criteria: children of both sexes with a primary diagnosis of MS-KWK. Patients with any chronic disease liable to cause malnutrition were excluded. Anthropometric parameters, clinical signs and biochemical indicators of malnutrition were assessed upon admission and again at discharge following application of the WHO guidelines. Univariate analysis was performed for each study variable; serum hemoglobin and albumin levels on admission and at discharge were compared, and data were subjected to bivariate analysis. RESULTS: Marasmus was diagnosed in 23.3% of children, kwashiorkor in 73.3% and marasmic kwashiorkor in 3.3%. The major clinical findings were: edema (70%), emaciation (40%), "flag sign" hair (42.86%), low serum albumin (93%) and anemia (80%). Thirteen children following the WHO-HILA protocol showed a significant nutritional status improvement (p<0.05), whereas no improvement was noted in the 17 children not treated according to the protocol. CONCLUSIONS: Application of the WHO-HILA protocol was associated with reduced morbimortality in children with marasmus-kwashiorkor malnutrition. Implementation of this protocol should therefore be considered in all children´s hospitals in countries where this disease is prevalent.

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Background: In 2007, the Hospital Infantil Los Ángeles (HILA) in Colombia implemented a slightly-modified version of the WHO guidelines for the diagnosis and management of malnutrition during childhood. Objective: To evaluate the efficacy of the WHO-HILA protocol in children hospitalized with severe, chronic marasmus and kwashiorkor malnutrition (MS-KWK) in 2007 and 2008. Material and methods: In this descriptive retrospective study the records of 100 children hospitalized with MSKWK were initially evaluated. Of these, 30 fulfilled the inclusion criteria: children of both sexes with a primary diagnosis of MS-KWK. Patients with any chronic disease liable to cause malnutrition were excluded. Anthropometric parameters, clinical signs and biochemical indicators of malnutrition were assessed upon admission and again at discharge following application of the WHO guidelines. Univariate analysis was performed for each study variable; serum hemoglobin and albumin levels on admission and at discharge were compared, and data were subjected to bivariate analysis. Results: Marasmus was diagnosed in 23.3% of children, kwashiorkor in 73.3% and marasmic kwashiorkor in 3.3%. The major clinical findings were: edema (70%), emaciation (40%), "flag sign" hair (42.86%), low serum albumin (93%) and anemia (80%). Thirteen children following the WHO-HILA protocol showed a significant nutritional status improvement (p < 0.05), whereas no improvement was noted in the 17 children not treated according to the protocol.Conclusions: Application of the WHO-HILA protocol was associated with reduced morbimortality in children with marasmus-kwashiorkor malnutrition. Implementation of this protocol should therefore be considered in all children´s hospitals in countries where this disease is prevalent (AU)

Introducción: En 2007, el Hospital Infantil de Los Ángeles (HILA) en Colombia implementó una versión del protocolo-OMS para el diagnóstico y tratamiento de la malnutrición en la infancia. Objetivo: Evaluar la aplicación del protocolo de la OMS-HILA en niños hospitalizados con marasmo y/o kwashiorkor (MS-KWK) durante 2007-2008. Material y métodos: En este estudio retrospectivo, se evaluaron 100 niños hospitalizados con MS-KWK; 30 cumplieron los criterios de inclusión: niños de ambos sexos con MS-KWK primario. Los pacientes con enfermedades crónicas que pudieran causar desnutrición fueron excluidos. Se evaluaron determinados parámetros antropométricos, y signos clínicos y bioquímicos de desnutrición según el protocolo de la OMS, al ingreso y al alta. Se realizó un análisis univariante; los niveles de hemoglobina y albúmina séricas fueron comparados al ingreso y al alta, y los datos fueron sometidos a análisis de dos variables. Resultados: Se diagnosticaron de marasmo al 23,3% de los niños, de kwashiorkor al 73,3% y de kwashiorkor marásmico al 3,3%. Los hallazgos clínicos más importantes fueron: edema (70%), emaciación (40%), "signo de bandera" (42,86%), albúmina baja (93%) y anemia (80%). Trece niños mostraron mejoría significativa del estado nutricional tras aplicar el protocolo OMS-HILA (p < 0,05), mientras que no ocurrió en 17 niños no tratados según el protocolo. Conclusiones: La aplicación del protocolo de la OMSHILA se asoció con una reducción de la morbimortalidad en los niños con desnutrición marasmo-kwashiorkor. La aplicación completa y continuada de este protocolo debe ser considerada en los hospitales infantiles de todos los países donde esta enfermedad es prevalente (AU)

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A set of 34 crude oils was analysed by GC-MS (SIM mode) and a suite of 28 diagnostic ratios (DR) calculated. They involved 18 ratios between biomarker molecules (hopanes, steranes, diasteranes and triaromatic steroids) and 10 quotients between polycyclic aromatic hydrocarbons. Three unsupervised pattern recognition techniques (i.e., principal components analysis, heatmap hierarchical cluster analysis and Kohonen neural networks) were employed to evaluate the final dataset and, thus, ascertain whether the crude oils grouped as a function of their geographical origin. In addition, an objective variable selection procedure based on Procrustes Rotation was undertaken to select a reduced set of DR that comprised for most of the information in the original data without loosing relevant information. A reduced set of four DR (namely; TA21, D2/P2, D3/P3 and B(a)F/4-Mpy) demonstrated to be sufficient to characterize the crude oils and the groups they formed.

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A case study is presented in which advanced chemical fingerprinting and data interpretation techniques are used to characterize and compare the weathering processes of six oil spillages made under controlled conditions (including the heavy oil released after the Prestige tanker sunk off the Galician coast-NW Spain on 2002). A tiered analytical approach using gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS) was applied along with two different approaches for 3-way analyses; namely, generalized Procrustes rotation, and matrix-augmented principal components analysis. Results showed that the two 3-way chemometric techniques leaded to essentially the same conclusions when analyzing three sets of compounds fingerprinting the spilled hydrocarbons (aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs) and a set of diagnostic ratios). A steady evolution on the weathering of the oils was observed with both techniques, but for the diagnostic ratios. The variables involved on the weathering were the lightest aliphatic hydrocarbons and a general combination of the PAHs, which differentiated mostly among the light and the heavy products (fuel oils).

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Identifying petroleum-related products released into the environment is a complex and difficult task. To achieve this, polycyclic aromatic hydrocarbons (PAHs) are of outstanding importance nowadays. Despite traditional quantitative fingerprinting uses straightforward univariate statistical analyses to differentiate among oils and to assess their sources, a multivariate strategy based on Procrustes rotation (PR) was applied in this paper. The aim of PR is to select a reduced subset of PAHs still capable of performing a satisfactory identification of petroleum-related hydrocarbons. PR selected two subsets of three (C(2)-naphthalene, C(2)-dibenzothiophene and C(2)-phenanthrene) and five (C(1)-decahidronaphthalene, naphthalene, C(2)-phenanthrene, C(3)-phenanthrene and C(2)-fluoranthene) PAHs for each of the two datasets studied here. The classification abilities of each subset of PAHs were tested using principal components analysis, hierarchical cluster analysis and Kohonen neural networks and it was demonstrated that they unraveled the same patterns as the overall set of PAHs.

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The capability of single-reflection near-IR (NIR) spectroscopy to differentiate, characterize and monitor the fate of a set of hydrocarbons spilled in the marine environment was compared with that of multiple-reflection horizontal attenuated total reflection mid-IR (ATR-MIR) spectroscopy. Multivariate pattern recognition techniques [principal component analysis (PCA), multivariate polynomial regression, cluster analysis and potential curves] were applied to unravel the major trends of the weathering processes of four generic types of crude oils and two heavy fuel oils spilled under controlled conditions for almost 4 months. A chemical interpretation of the NIR spectra related the weathering processes and the PCA loadings, which had not already been done in the literature. Weathering for both light and heavy products was characterized by a contrast among the linear aliphatic structures (more volatile and easy to degrade) and the branched and aromatic structures (more recalcitrant). Potential curves were applied to model each product and determine objectively whether unknown samples could be classified correctly. Polynomial regression on the PCA scores was employed to evaluate the time elapsed from the oil spillage to its sampling; this represents a new approach to assess the age of a hydrocarbon lump. In general, NIR spectroscopy yielded good results when light crude oils were studied, whereas ATR-MIR spectroscopy led to satisfactory results for both light and heavy products.

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This paper compares the weathering patterns of two similar fuel oils: a fuel oil spilled after a ship accident (Prestige-Nassau, off the Galician coast -NW Spain-) and a fuel designed to cope with the numerous quests for samples to carry out scientific studies (IFO). Comparative studies were made to evaluate the capability of common fingerprinting analytical techniques to differentiate the fuels, as well as their capabilities to monitor their weathering. The two products were spilled under controlled conditions during ca. four months to assess how they evolved on time. Mid-IR spectrometry and gas chromatography (flame ionization and mass spectrometry detectors) were used. IR indexes related to total aromaticity, type of substituents (branched or linear chains) and degree of aromatic substitution reflected well the differences between the fuels during weathering. Regarding the chromatographic measurements, the n-alkanes became highly reduced for both fuel oils and it was found that the PAHs of the synthetic fuel (IFO) were more resistant to weathering. Regarding biomarkers, the different profiles of the steranes, diasteranes and triaromatic steroids allowed for a simple differentiation amongst the two products. The %D2/P2 ratio differentiated both products whereas the %N3/P2 one ordered the samples according to the extent of their weathering.

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A set of 34 worldwide crude oils, 12 distilled products (kerosene, gas oils, and fuel oils) and 45 oil samples taken from several Galician beaches (NW Spain) after the wreckage of the Prestige tanker off the Galician coast was studied. Gas chromatography with flame ionization detection was combined with chemometric multivariate pattern recognition methods (principal components analysis, cluster analysis and Kohonen neural networks) to differentiate and characterize the Prestige fuel oil. All multivariate studies differentiated between several groups of crude oils, fuel oils, distilled products, and samples belonging to the Prestige's wreck and samples from other illegal discharges. In addition, a reduced set of 13 n-alkanes out of 36, were statistically selected by Procrustes Rotation to cope with the main patterns in the datasets. These variables retained the most important characteristics of the data set and lead to a fast and cheap analytical screening methodology.

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Three different approaches for 3-way analyses, namely, Procrustes rotation, parallel factor analysis (PARAFAC) and matrix-augmented principal component analysis, have been compared considering a four-seasons study on soil pollution. Each sampling season comprised 92 roadsoil samples and 12 analytical variables (heavy metals, loss on ignition, pH and humidity). Results show that the three chemometric techniques lead to essentially the same conclusions. Hence, Procrustes rotation, a mathematical technique scarcely applied in analytical chemistry, revealed as a useful tool for 3-way data analysis with potential advantages, including its conceptual simplicity and straightforward interpretation of the results. A novel application of the consensus vectors allowed definition of "consensus scores" so that visualization of the samples and temporal patterns can be made. Results also suggested that the trilinearity assumption imbedded in PARAFAC is essentially fulfilled when studying the temporal evolution of an environmental system where no new pollution sources appear during the course of the study.

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The Environmental Laboratories Automation Software System or PALMA (Spanish abbreviation) was developed by a multidisciplinary team in order to support the main tasks of heterogeneous air quality control networks. The software process for PALMA development, which can be perfectly applied to similar multidisciplinary projects, was (a) well-defined, (b) arranged between environmental technicians and informatics, (c) based on quality guides, and (d) clearly user-centred. Moreover, it introduces some interesting advantages with regard to the classical step-by-step approaches. PALMA is a web-based system that allows 'off-line' and automated telematic data acquisition from distributed inmission stations belonging not only to homogeneous but also to heterogeneous air quality control networks. It provides graphic and tabular representations for a comprehensive and centralised analysis of acquired data, and considers the daily work that is associated with such networks: validation of the acquired data, alerts with regard to (periodical) tasks (e.g., analysers verification), downloading of files with environmental information (e.g., dust forecasts), etc. The implantation of PALMA has provided qualitative and quantitative improvements in the work performed by the people in charge of the considered control network.

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A fast analytical tool based on attenuated total reflectance mid-IR spectrometry is presented to evaluate the origin of spilled hydrocarbons and to monitor their fate on the environment. Ten spectral band ratios are employed in univariate and multivariate studies (principal components analysis, cluster analysis, density functions - potential curves - and Kohonen self organizing maps). Two indexes monitor typical photooxidation processes, five are related to aromatic characteristics and three study aliphatic and branched chains. The case study considered here comprises 45 samples taken on beaches (from 2002 to 2005) after the Prestige carrier accident off the Galician coast and 104 samples corresponding to weathering studies deployed for the Prestige's fuel, four typical crude oils and a fuel oil. The univariate studies yield insightful views on the gross chemical evolution whereas the multivariate studies allow for simple and straightforward elucidations on whether the unknown samples match the Prestige's fuel. Besides, a good differentiation on the weathering patterns of light and heavy products is obtained.

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El Arsénico en el agua de bebida es un importante problema ambiental en amplias zonas de Argentina. El cáncer, especialmente de piel, es uno de los riesgos asociados con el consume crónico de agua con elevados tenores de arsénico. Los valores máximos recomendados por la Organización Mundial de la Salud son de 0.010mg/l. La Ley Provincial Nº 11.220 de 1995 obliga a todos los servicios de agua potable a suministrar agua de bebida con concentraciones de arsénico de 0.050 mg/l (Límite Recomendado) o menores, aunque las normas en vigencia admiten plazos para alcanzar condiciones normales de operación y el límite recomendado, período durante el cual debe el prestador cumplir con el "límite obligatorio" de 0.100 mg/l. Estos valores pueden significar riesgos para la salud de las poblaciones expuestas. Se evalúa el riego relativo para desarrollar cáncer de piel en la población rural de Máximo Paz

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