[Maintenance of chest compressions skill in cardiopulmonary resuscitation in primary health care professionals: Quasi-experimental study]. / Mantenimiento de la habilidad de las compresiones torácicas en reanimación cardiopulmonar en profesionales de la atención primaria de salud: estudio cuasiexperimental.

OBJECTIVE: To validate the efficacy of brief CPR training with dual feedback to maintain the ability to perform quality chest compressions. MATERIALS AND METHODS: Quasi-experimental study with two groups to evaluate a brief theoretical training followed by a practice with manikin with feedback; Participants: 155 health and non-health professionals from 5 primary care health centers of urban area (43 losses); Main measurements: Characteristics of compressions that were measured before and after the brief training and their maintenance at 3 and 6 months according to the study group. The effect of training and maintenance of skills were analyzed using multiple linear regression models. RESULTS: 155 participants were included, mean age 39.7 years (SD=12.0) with 82.7% female. The training effect had an improvement in mean compression depth (pre-post difference: 3.5, P<.001), total compressions with adequate depth (pre-post difference: 0.2, P<.001) and Total Compressions with Adequate Rhythm (pre-post difference: 0.4, P<.001). The second phase was completed by 112 participants (72.2%). Compression skills declined at 3 months and were lower at 6 months, although the loss of skills was not statistically significant between the two groups. CONCLUSIONS: An individualized, brief training action with feedback immediately improves the quality of compressions. The progressive loss of skills from 3 to 6 months is not relevant.

Healthy dietary pattern and their corresponding gut microbiota profile are linked to a lower risk of type 2 diabetes, independent of the presence of obesity.

BACKGROUND: Prediabetes and old age are both high risk factors for developing Type 2 Diabetes (T2D), while obesity is one of the most important factors triggering the disease. Nutritional interventions are the most effective tool for preventing T2D, as they improve different biochemical and anthropometric outcomes and growth-promoting/inhibiting gut microbiota populations. However, to date there are no specific dietary recommendations to stop the development of T2D in elderly groups, for whom hypocaloric diets and other commonly used weight-loss programs could be considered dangerous. The objective of our study, thus, was to understand the impact of dietary patterns on T2D risk as related to gut microbiota profile in obese and non-obese elderly prediabetic subjects. METHODS: A cross-sectional study was performed in 182 subjects ≥65 years old with prediabetes, divided into obese (OB) or non-obese (NOB) subgroups, and their risk of developing T2D was measured according to FINDRISK score and biochemical parameters. Also, clusters into different dietary patterns in each group by PCA analysis was related with gut microbiota, which was analyzed from stool samples by qPCR. The creation of clusters was used to re-evaluate T2D risk. RESULTS: OB was at higher risk of developing T2D and showed worse metabolic outcomes. Unhealthier and healthier dietary pattern clusters were observed for both OB (OB-6 and OB-5 respectively) and NOB (NOB-2 and NOB-3 respectively) groups. Results obtained from the gut microbiota showed that only Prevotella was higher in NOB, but when comparisons were made between clusters, a clear relation with dietary pattern was observed; showing in healthier dietary clusters a decrease in Prevotella, an increase of Faecalibacterium prausnitzii and an increase in lactic acid bacteria. T2D risk was greater in the obese group between unhealthier dietary clusters. No difference between healthier dietary clusters was observed. CONCLUSION: A healthy dietary pattern and the growth-promoting beneficial and growth-inhibiting disadvantageous gut microbiota populations linked to it provide protection against the development of T2D in an obese population with advanced age and preDM.

Galician consensus on management of cardiotoxicity in breast cancer: risk factors, prevention, and early intervention.

This Galician consensus statement is a joint oncologists/cardiologists initiative indented to establish basic recommendations on how to prevent and to manage the cardiotoxicity in breast cancer with the aim of ensuring an optimal cardiovascular care of these patients. A clinical screening of the patients before treatment is recommended to stratify them into a determined risk group based on their intrinsic cardiovascular risk factors and those extrinsic arose from breast cancer therapy, thereby providing individualized preventive and monitoring measures. Suitable initial and ongoing assessments for patients with low and moderate/high risk and planned treatment with anthracyclines and trastuzumab are given; also, measures aimed at preventing and correcting any modifiable risk factor are pointed out .

Apical negative pressure irrigation versus syringe irrigation: a systematic review of cleaning and disinfection of the root canal system.

The aim of this study was to systematically review and critically analyse the published data on the treatment outcome (primary outcome) and on the cleaning and disinfection of root canals (secondary outcomes) achieved by negative pressure irrigation as compared to syringe irrigation. An electronic search was conducted in EMBASE, LILACS, PubMed, SciELO, Scopus and Web of Knowledge using both free-text keywords and controlled vocabulary. Additional studies were sought through hand searching of endodontic journals and of the relevant chapters of endodontic textbooks. No language restriction was imposed. The retrieved studies were screened by two reviewers according to predefined criteria. Included studies were critically appraised and the extracted data were arranged in tables. The electronic search and hand search retrieved 489 titles. One clinical study and 14 in vitro studies were finally included in the review; none of these studies assessed treatment outcome, four studies assessed the antimicrobial effect, seven studies evaluated the removal of pulp tissue remnants, and four studies investigated the removal of hard tissue debris or both hard tissue debris and pulp tissue remnants. Poor standardization and description of the protocols was evident. Inconclusive results were reported about the cleaning and disinfection accomplished by the two irrigation methods. Negative pressure irrigation was more effective under certain conditions when compared to suboptimal syringe irrigation; however, the variability of the protocols hindered quantitative synthesis. There is insufficient evidence to claim general superiority of any one of these methods. The level of the available evidence is low, and the conclusions should be interpreted with caution.

Función y respaldo a la asociación de pacientes con psoriasis en España según sus miembros: estudio descriptivo transversal / The Spanish psoriasis patients’ association according to its members: cross-sectional descriptive study of members’ opinions of the association’s functions

INTRODUCCIÓN: Las asociaciones de pacientes son un elemento más del sistema sanitario, sin embargo en España se desconoce la funcionalidad y el respaldo que tienen según sus propios asociados. OBJETIVO: Estudiar la funcionalidad de la principal asociación española de pacientes y familiares afectados por la psoriasis según sus propios socios. MATERIAL Y MÉTODOS: Estudio mediante un cuestionario autoadministrado a una muestra de socios y/o simpatizantes (población total = 26.349 personas). Se estudió la credibilidad, confianza y satisfacción y se comparó con otros agentes sanitarios. El cuestionario de funcionalidad se analizó con un modelo de Rasch, y se examinó si había diferencias entre grupos de participantes con la prueba de ANOVA. RESULTADOS: Participaron 746 socios y/o simpatizantes (tasa de respuesta 2,83%). La credibilidad de la asociación se situó tras la de los especialistas que tratan la psoriasis. El respaldo medio a la función de la asociación fue notable (7,53 en una escala de 0 a 10). Según los socios las funciones mejor puntuadas se relacionaban con acciones colectivas para sensibilizar a la sociedad sobre el problema de la psoriasis, en cambio, tuvieron una menor valoración las acciones relacionadas con los servicios de atención personalizada. Solo hubo diferencias significativas (p < 0,05) en el respaldo a la asociación en función del nivel académico de los participantes. CONCLUSIONES: Las asociaciones son unas instituciones que contribuyen a la difusión de información de la enfermedad, que cuidan y representan a los pacientes. Los profesionales de salud e instituciones deberían tenerlas en cuenta para afrontar la psoriasis y diseñar políticas de salud efectivas

INTRODUCTION: Patient associations form part of health care systems, but little is known about how their members' view the functionality of these associations and whether they endorse their goals and activities. OBJECTIVE: To study how the members of the leading Spanish association of patients with psoriasis and their relatives view the group's functioning. MATERIAL AND METHODS: Survey study using a self-administered questionnaire answered by members of the association (total membership, 26 349 persons). The credibility of the association and respondents' confidence in and satisfaction with it were studied and compared with their attitudes toward other agents in the health care system. A Rasch model was used to analyze respondents' ranking of functions. Analysis of variance was used to study between-group differences. RESULTS: A total of 746 members participated (response rate 2.83%). The association's credibility was rated in second place, after that of specialists who treat psoriasis. Support for the association functions was good (7.53 on a scale of 0 to 10). The function the members rated highest was the raising of societal awareness of psoriasis and its problems. Rated lowest were functions related to personal services for members. Educational level was the only participant factor associated with significant differences in evaluations (P < .05). CONCLUSIONS: The psoriasis association contributes by disseminating information about the disease and patient care, and it serves to represent patients. Health professionals and institutions should take the association into account in their efforts to deal with the disease and in designing effective policies

The Spanish Psoriasis Patients' Association According to Its Members: Cross-Sectional Descriptive Study of Members' Opinions of the Association's Functions. / Función y respaldo a la asociación de pacientes con psoriasis en España según sus miembros: estudio descriptivo transversal.

INTRODUCTION: Patient associations form part of health care systems, but little is known about how their members' view the functionality of these associations and whether they endorse their goals and activities. OBJECTIVE: To study how the members of the leading Spanish association of patients with psoriasis and their relatives view the group's functioning. MATERIAL AND METHODS: Survey study using a self-administered questionnaire answered by members of the association (total membership, 26 349 persons). The credibility of the association and respondents' confidence in and satisfaction with it were studied and compared with their attitudes toward other agents in the health care system. A Rasch model was used to analyze respondents' ranking of functions. Analysis of variance was used to study between-group differences. RESULTS: A total of 746 members participated (response rate 2.83%). The association's credibility was rated in second place, after that of specialists who treat psoriasis. Support for the association functions was good (7.53 on a scale of 0 to 10). The function the members rated highest was the raising of societal awareness of psoriasis and its problems. Rated lowest were functions related to personal services for members. Educational level was the only participant factor associated with significant differences in evaluations (P<.05). CONCLUSIONS: The psoriasis association contributes by disseminating information about the disease and patient care, and it serves to represent patients. Health professionals and institutions should take the association into account in their efforts to deal with the disease and in designing effective policies.

Strains of Enterococcus faecalis differ in their ability to coexist in biofilms with other root canal bacteria.

AIM: To investigate the relationship between protease production and the ability of Enterococcus faecalis strains to coexist in biofilms with other bacteria commonly recovered from infected root canals. METHODOLOGY: Biofilms with bacteria in mono-, dual- and four-species communities were developed in flow chambers. The organisms used were Lactobacillus salivarius, Streptococcus gordonii and Actinomyces naeslundii and E. faecalis strains, GUL1 and OG1RF. Biovolume and species distribution were examined using 16S rRNA fluorescence in situ hybridization in combination with confocal microscopy and image analysis. The full proteome of the E. faecalis strains was studied using two-dimensional gel electrophoresis. Spots of interest were identified using tandem mass spectroscopy and quantified using Delta 2D software. RESULTS: All bacteria formed biofilms and an anova analysis revealed that the biofilm biomass increased significantly (P ≤ 0.01) between 6 and 24 h. L. salivarius, S. gordonii and A. naeslundii formed mutualistic biofilm communities, and this pattern was unchanged when E. faecalis GUL1 was included in the consortium. However, with OG1RF, L. salivarius and S. gordonii were outcompeted in a 24-h biofilm. Proteomic analysis revealed that OG1RF secreted higher levels of proteases, GelE (P = 0.02) and SprE (P = 0.002) and a previously unidentified serine protease (P = 0.05), than GUL1. CONCLUSIONS: Different strains of E. faecalis can interact synergistically or antagonistically with a consortium of root canal bacteria. A possible mechanism underlying this, as well as potential differences in virulence, is production of different levels of proteases, which can cause detachment of neighbouring bacteria and tissue damage.

Conflictos de intereses en investigación clínica en el área de atención primaria de salud / Conflicts of interests in clinical research in primary health care

En investigación biomédica los conflictos de intereses entre profesionales y pacientes pueden ser un problema ético. Ninguna de las normas legales vigentes en España menciona si el investigador debe clarificar a los participantes de un estudio clínico todos los motivos por los que le es propuesto participar. En este artículo, los conflictos de intereses en investigación se analizan en el contexto de atención primaria y se clarifica la importancia de tenerlos en cuenta. En esta área clínica los conflictos de intereses pueden afectar a la confianza terapéutica y alterar la función social que tiene. Finalmente, se sugieren algunas estrategias de carácter práctico que pueden facilitar a los participantes tomar la decisión de participar en un estudio clínico con mayor voluntariedad y autonomía (AU)

Conflicts of interests between professionals and patients in biomedical research, is an ethical problem. None of the laws in Spain mention whether the clinical researcher has to clarify to participants the reasons why it proposes them to participate in a clinical trial. In this article, conflicts of interests in research are discussed in the context of primary healthcare. In this area conflicts of interests might alter the confidence between patients and healthcare professionals. Finally, we suggest some practical strategies that can help participants make the decision to participate in a clinical trial more willingly and freely (AU)

[Conflicts of interests in clinical research in primary health care]. / Conflictos de intereses en investigación clínica en el área de atención primaria de salud.

Conflicts of interests between professionals and patients in biomedical research, is an ethical problem. None of the laws in Spain mention whether the clinical researcher has to clarify to participants the reasons why it proposes them to participate in a clinical trial. In this article, conflicts of interests in research are discussed in the context of primary healthcare. In this area conflicts of interests might alter the confidence between patients and healthcare professionals. Finally, we suggest some practical strategies that can help participants make the decision to participate in a clinical trial more willingly and freely.

Una bioética clínica para la atención primaria de salud / Clinical bioethics for primary health care

El modelo de toma de decisiones éticas en el área de atención primaria difiere de otras áreas asistenciales. Desde la perspectiva ética es relevante incorporar estas particularidades al método de deliberación. El presente artículo justifica la necesidad de un procedimiento de deliberación ética propio para la atención primaria y realiza una propuesta metodológica. Este proceso de decisión es flexible y requiere un sistema de salud participativo. Esta propuesta tiene la finalidad de facilitar la adquisición de responsabilidad sobre la salud personal y colectiva, e implica a profesionales y ciudadanos de igual manera (AU)

The clinical decision making process with ethical implications in the area of primary healthcare differs from other healthcare areas. From the ethical perspective it is important to include these issues in the decision making model. This dissertation explains the need for a process of bioethical deliberation for Primary Healthcare, as well as proposing a method for doing so. The decision process method, adapted to this healthcare area, is flexible and requires a more participative Healthcare System. This proposal involves professionals and the patient population equally, is intended to facilitate the acquisition of responsibility for personal and community health (AU)

A device to record ultra-rapid cooling profiles.

This work deals with the construction and performance of a measuring system capable of estimating temperature at sufficiently high speed (up to 1000 samples per sec). Due to its simple design and the utilization of standard materials, it could serve to recording the cooling profile of ultra-rapid procedures. An immersion device was also developed with the purpose of normalize the penetration speed of the sample in the LN2. The device allows also the comparative analysis of different cooling profiles. The system consists of an immersion device of the sample in the cooling agent, a temperature measurement system developed by Kleihans F and a laptop computer. To test the system, we recorded the cooling profiles of 10 uL of distilled water and 6 M glycerol solution, obtaining a cooling rate of 8732 C/min and 4441 C/min respectively. Also we determine a cooling rate of 204.012 C/min during the immersion of the thermocouple assembly in LN2. Although, the same device, with small technical modifications related to the handling of the sample, could be used to evaluate the recovery from LN2 temperature to room temperature (re-warming).

[Clinical bioethics for primary health care]. / Una bioética clínica para la atención primaria de salud.

The clinical decision making process with ethical implications in the area of primary healthcare differs from other healthcare areas. From the ethical perspective it is important to include these issues in the decision making model. This dissertation explains the need for a process of bioethical deliberation for Primary Healthcare, as well as proposing a method for doing so. The decision process method, adapted to this healthcare area, is flexible and requires a more participative Healthcare System. This proposal involves professionals and the patient population equally, is intended to facilitate the acquisition of responsibility for personal and community health.

Resonancia magnética de mama: cambios en la imagen del cáncer tratado con neoadyuvancia. Correlación con subtipos moleculares / Breast MR imaging changes after neoadjuvant chemotherapy: correlation with molecular subtypes

Objetivo. La RM es la técnica de imagen que mejor valora la respuesta a la quimioterapia neoadyuvante en el cáncer de mama localmente avanzado. Los objetivos son: primero, cuantificar la respuesta en los subtipos moleculares; segundo, describir las variaciones morfológicas y dinámicas, y tercero, valorar si el fenotipo molecular se modifica tras la quimioterapia. Material y métodos. Estudio retrospectivo de 75 carcinomas, en 69 pacientes con quimioterapia neoadyuvante. Se realizó RM pre y post-tratamiento. La respuesta se clasificó en: respuesta completa; respuesta parcial mayor; respuesta parcial menor y sin respuesta, cuantificando cada una en cada subtipo molecular (luminal A, luminal B, Herb2+ y triple negativo). Los cambios morfológicos fueron: reducción concéntrica, fragmentación, realce ductal y necrosis. Los cambios dinámicos afectaron al pico de intensidad máxima y al realce post-inicial. Resultados. En los 4 subtipos moleculares se observaron los 4 tipos de respuesta. El triple negativo tuvo 84,6% de buenas respuestas, seguido del luminal B (76,9%), luminal A (75,6%), y Herb 2+ (69,2%). El cambio morfológico que predominó fue la reducción concéntrica en el 75% y el dinámico fue la disminución del pico de intensidad máxima, < 100%, en el 64,2%, con predominio de curvas tipo I y II en el 85,7%. Conclusiones. El subtipo triple negativo es el que mejor respondió a la quimioterapia neoadyuvante. Los cambios más frecuentes fueron la reducción concéntrica y la disminución del pico de intensidad máxima con menos curvas de lavado. El cambio del fenotipo molecular fue del 12,2%, entre la muestra al diagnóstico y el estudio final (AU)

Objective. MRI is the imaging technique that is best suited to evaluating the response to neoadjuvant chemotherapy for locally advanced breast cancer. We aimed to a) quantify the response in the molecular subtypes, b) describe the morphological and dynamic variation, and c) determine whether the molecular phenotype changes after chemotherapy. Material and methods. This is a retrospective study of 75 carcinomas in 69 patients who underwent MRI both before and after neoadjuvant chemotherapy. The response to treatment was classified as a) complete response, b) major partial response, c) minor partial response, or d) no response. We quantified the response in each molecular subtype (Luminal A, Luminal B, Her2+, and triple negative). The morphological changes were classified as a) concentric reduction, b) fragmentation, c) ductal enhancement, or d) necrosis. The dynamic changes affected the maximum intensity peak and the post-initial enhancement. Results. In the 4 molecular subtypes, the 4 types of response were seen. The response was good in 84.6% of the triple negative subtype, in 76.9% of the Luminal B subtype, in 75.6% of the Luminal A subtype, and in 69.2% of the Her2+ subtype. The predominant morphological change was concentric reduction (75%). The predominant dynamic change was a decrease in the maximum intensity peak (<100% in 64.2%), and type I or II curves were seen in 85.7%. Conclusions. The triple negative subtype responded best to neoadjuvant chemotherapy. The most common changes were concentric reduction and a decrease in the maximum intensity peak, with fewer washout curves. We observed a change in the molecular phenotype between the specimen at diagnosis and the final study in 12.2% of cases (AU)

Regulation of bacteriocin production and cell death by the VicRK signaling system in Streptococcus mutans.

The VicRK two-component signaling system modulates biofilm formation, genetic competence, and stress tolerance in Streptococcus mutans. We show here that the VicRK modulates bacteriocin production and cell viability, in part by direct modulation of competence-stimulating peptide (CSP) production in S. mutans. Global transcriptome and real-time transcriptional analysis of the VicK-deficient mutant (SmuvicK) revealed significant modulation of several bacteriocin-related loci, including nlmAB, nlmC, and nlmD (P < 0.001), suggesting a role for the VicRK in producing mutacins IV, V, and VI. Bacteriocin overlay assays revealed an altered ability of the vic mutants to kill related species. Since a well-conserved VicR binding site (TGTWAH-N(5)-TGTWAH) was identified within the comC coding region, we confirmed VicR binding to this sequence using DNA footprinting. Overexpression of the vic operon caused growth-phase-dependent repression of comC, comDE, and comX. In the vic mutants, transcription of nlmC/cipB encoding mutacin V, previously linked to CSP-dependent cell lysis, as well as expression of its putative immunity factor encoded by immB, were significantly affected relative to the wild type (P < 0.05). In contrast to previous reports that proposed a hyper-resistant phenotype for the VicK mutant in cell viability, the release of extracellular genomic DNA was significantly enhanced in SmuvicK (P < 0.05), likely as a result of increased autolysis compared with the parent. The drastic influence of VicRK on cell viability was also demonstrated using vic mutant biofilms. Taken together, we have identified a novel regulatory link between the VicRK and ComDE systems to modulate bacteriocin production and cell viability of S. mutans.

Breast MR imaging changes after neoadjuvant chemotherapy: correlation with molecular subtypes.

OBJECTIVE: MRI is the imaging technique that is best suited to evaluating the response to neoadjuvant chemotherapy for locally advanced breast cancer. We aimed to a) quantify the response in the molecular subtypes, b) describe the morphological and dynamic variation, and c) determine whether the molecular phenotype changes after chemotherapy. MATERIAL AND METHODS: This is a retrospective study of 75 carcinomas in 69 patients who underwent MRI both before and after neoadjuvant chemotherapy. The response to treatment was classified as a) complete response, b) major partial response, c) minor partial response, or d) no response. We quantified the response in each molecular subtype (Luminal A, Luminal B, Her2+, and triple negative). The morphological changes were classified as a) concentric reduction, b) fragmentation, c) ductal enhancement, or d) necrosis. The dynamic changes affected the maximum intensity peak and the post-initial enhancement. RESULTS: In the 4 molecular subtypes, the 4 types of response were seen. The response was good in 84.6% of the triple negative subtype, in 76.9% of the Luminal B subtype, in 75.6% of the Luminal A subtype, and in 69.2% of the Her2+ subtype. The predominant morphological change was concentric reduction (75%). The predominant dynamic change was a decrease in the maximum intensity peak (<100% in 64.2%), and type I or II curves were seen in 85.7%. CONCLUSIONS: The triple negative subtype responded best to neoadjuvant chemotherapy. The most common changes were concentric reduction and a decrease in the maximum intensity peak, with fewer washout curves. We observed a change in the molecular phenotype between the specimen at diagnosis and the final study in 12.2% of cases.

Chitosan nanoparticles affect the acid tolerance response in adhered cells of Streptococcus mutans.

In this study we evaluated the effect of chitosan nanoparticles on the acid tolerance response (ATR) of adhered Streptococcus mutans. An ATR was induced by exposing S. mutans to pH 5.5 for 2 h and confirmed by exposing the acid-adapted cells to pH 3.5 for 30 min, with the majority of cells appearing viable according to the LIVE/DEAD® technique. However, when chitosan nanoparticles were present during the exposure to pH 5.5, no ATR occurred as most cells appeared dead after the pH 3.5 shock. We conclude that the chitosan nanoparticles tested had the ability to hinder ATR induction in adhered S. mutans.

In situ analysis of multispecies biofilm formation on customized titanium surfaces.

Many studies to identify surfaces that enhance the incorporation of dental implants into bone and soft-tissue have been undertaken previously. However, to succeed in the clinical situation, an implant surface must not support development of microbial biofilms with a pathogenic potential. As a first step in investigating this, we used two-species and three-species biofilm models with 16S ribosomal RNA fluorescence in situ hybridization and confocal laser scanning microscopy to examine the effect of surface characteristics on biofilm formation by species that can colonize titanium implants in vivo: Streptococcus sanguinis, Actinomyces naeslundii and Lactobacillus salivarius. Surfaces blasted with Al(2) O(3) (S(a) = 1.0-2.0 µm) showed a seven-fold higher bacterial adhesion after 2 h than turned surfaces (S(a) = 0.18 µm) whereas porous surfaces, generated by anodic oxidation (S(a) = 0.4 µm), showed four-fold greater adhesion than turned surfaces. Hence, increased roughness promoted adhesion, most likely through protection of bacteria from shear forces. Chemical modification of the blasted and oxidized surfaces by incorporation of Ca(2+) ions reduced adhesion compared with the corresponding non-modified surfaces. After 14 h, biofilm growth occurred in the three-species model but not in the two-species consortium (containing S. sanguinis and A. naeslundii only). The biofilm biovolume on all surfaces was similar, suggesting that the influence of surface characteristics on adhesion was compensated for by biofilm development.

Response of intertidal macrobenthic communities to long term human induced changes in the Eo estuary (Asturias, Spain): implications for environmental management.

Long term macrobenthos data together with physical habitat parameters were analysed to investigate spatial and temporal changes at an estuary under different anthropogenic pressures, mainly increasing shellfish farming. The aim was to assess the possible impacts of these pressures on the macrobenthic communities by comparing a period before and after changes in these pressures. Benthic samples were seasonally collected in 1990 (before major anthropogenic changes), 2000 and 2005 at the same sampling stations located on three different habitats in the Eo estuary (Northern Spanish coast). Multivariate and univariate methods were used to assess spatial variability of benthic assemblages and to compare community changes over time. Data from 1990 was assumed as the reference situation to appraise the subsequent impacts. We observed a significant spatial variability of the benthic assemblages in the system as a function of habitat heterogeneity in relation to sediment composition, presence/absence and density of seagrasses, and hydrodynamic regime. Changes were detected in the community composition at all sites during this 15 year period. The extent of changes was related to initial community conditions, rather than the intensity of the pressure. The results suggest that the responses of the benthic communities to human induced perturbations occurring in the system are largely dependent on its intrinsic buffer capacity, and that these communities have been able to cope with an increasing environmental stress (organic enrichment). In conclusion, to keep shellfish farming at a sustainable level without undesirable impacts, the disturbance intensity must be kept below the system carrying capacity. This will allow natural communities to cope with pressures and thus avoid further deterioration in ecological quality.

Ecological status assessment in the lower Eo estuary (Spain). The challenge of habitat heterogeneity integration: a benthic perspective.

The implementation of the European Water Framework Directive (WFD) requires evaluation of the ecological status (ES) of benthic communities in coastal and transitional water systems, and the intercalibration of assessment methodologies therefore becomes a research challenge. Our aim was to test the suitability of applying the M-AMBI index to assess the status of the Eo estuary (northern coast of Spain). Our results showed that M-AMBI was influenced by the natural variability of benthic communities, and presented an apparent dependence on habitat characteristics. Consequently, the definition of homogeneous areas in transitional water systems should be based on the salinity gradient combined with other factors. To achieve an accurate ES assessment, habitat-specific reference conditions should then be defined prior to the application of M-AMBI; this necessitates dividing an estuary into several sections, which may be classified as different ESs. From this perspective, a novel approach to integrate habitat heterogeneity in a global ES assessment was tested.