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Arthropod biomass is a key element in ecosystem functionality and a basic food item for many species. It must be estimated through traditional costly field sampling, normally at just a few sampling points. Arthropod biomass and plant productivity should be narrowly related because a large majority of arthropods are herbivorous, and others depend on these. Quantifying plant productivity with satellite or aerial vehicle imagery is an easy and fast procedure already tested and implemented in agriculture and field ecology. However, the capability of satellite or aerial vehicle imagery for quantifying arthropod biomass and its relationship with plant productivity has been scarcely addressed. Here, we used unmanned aerial vehicle (UAV) and satellite Sentinel-2 (S2) imagery to establish a relationship between plant productivity and arthropod biomass estimated through ground-truth field sampling in shrub steppes. We UAV-sampled seven plots of 47.6-72.3 ha at a 4-cm pixel resolution, subsequently downscaling spatial resolution to 50 cm resolution. In parallel, we used S2 imagery from the same and other dates and locations at 10-m spatial resolution. We related several vegetation indices (VIs) with arthropod biomass (epigeous, coprophagous, and four functional consumer groups: predatory, detritivore, phytophagous, and diverse) estimated at 41-48 sampling stations for UAV flying plots and in 67-79 sampling stations for S2. VIs derived from UAV were consistently and positively related to all arthropod biomass groups. Three out of seven and six out of seven S2-derived VIs were positively related to epigeous and coprophagous arthropod biomass, respectively. The blue normalized difference VI (BNDVI) and enhanced normalized difference VI (ENDVI) showed consistent and positive relationships with arthropod biomass, regardless of the arthropod group or spatial resolution. Our results showed that UAV and S2-VI imagery data may be viable and cost-efficient alternatives for quantifying arthropod biomass at large scales in shrub steppes. The relationship between VI and arthropod biomass is probably habitat-dependent, so future research should address this relationship and include several habitats to validate VIs as proxies of arthropod biomass.

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Geographical distribution of parasite species can provide insights into the evolution and diversity of parasitic communities. Biogeography of marine parasites is poorly known, especially because it requires an understanding of host-parasite interactions, information that is rare, especially over large spatial scales. Here, we have studied the biogeographical patterns of dactylogyrid parasites of chaetodontids, one of the most well-studied fish families, in the tropical Indo-west Pacific region. Dactylogyrid parasites were collected from gills of 34 butterflyfish species (n=560) at nine localities within an approximate area of 62millionkm2. Thirteen dactylogyrid species were identified, with richness ranging from 6 to 12 species at individual localities. Most dactylogyrid communities were dominated by Haliotrema angelopterum or Haliotrema aurigae, for which relative abundance was negatively correlated (ρ=-0.59). Parasite richness and diversity were highest in French Polynesia and the Great Barrier Reef (Australia) and lowest in Palau. Three biogeographic regions were identified based on dactylogyrid dissimilarities: French Polynesia, characterised by the dominance of H. angelopterum, the western Pacific region dominated by H. aurigae, and Ningaloo Reef (Australia), dominated by Euryhaliotrema berenguelae. Structure of host assemblages was the main factor explaining the dissimilarity (turnover and nestedness components of the Bray-Curtis dissimilarity and overall Bray-Curtis dissimilarity) of parasite communities between localities, while environment was only significant in the turnover of parasite communities and overall dissimilarity. Spatial structure of localities explained only 10% of the turnover of parasite communities. The interaction of the three factors (host assemblages, environment and spatial structure), however, explained the highest amounts of variance of the dactylogyrid communities, indicating a strong colinearity between the factors. Our findings show that spatial arrangement of chaetodontid dactylogyrids in the tropical Indo-west Pacific is primarily characterised by the turnover of the main Haliotrema spp., which is mainly explained by the structure of host assemblages.

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Secondary metabolites play a crucial role in marine invertebrate chemical ecology. Thus, it is of great importance to understand factors regulating their production and sources of variability. This work aimed to study the variability of the bromotyrosine derivatives in the Mediterranean sponge Aplysina cavernicola, and also to better understand how biotic (reproductive state) and abiotic factors (seawater temperature) could partly explain this variability. Results showed that the A. cavernicola reproductive cycle has little effect on the variability of the sponges' secondary metabolism, whereas water temperature has a significant influence on the production level of secondary metabolites. Temporal variability analysis of the sponge methanolic extracts showed that bioactivity variability was related to the presence of the minor secondary metabolite dienone, which accounted for 50 % of the bioactivity observed. Further bioassays coupled to HPLC extract fractionation confirmed that dienone was the only compound from Aplysina alkaloids to display a strong bioactivity. Both dienone production and bioactivity showed a notable increase in October 2008, after a late-summer warming episode, indicating that A. cavernicola might be able to induce chemical changes to cope with environmental stressors.

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Protein kinase Cα (PKCα) can phosphorylate the epidermal growth factor receptor (EGFR) at threonine 654 (T654) to inhibit EGFR tyrosine phosphorylation (pY-EGFR) and the associated activation of downstream effectors. However, upregulation of PKCα in a large variety of cancers is not associated with EGFR inactivation, and factors determining the potential of PKCα to downregulate EGFR are yet unknown. Here, we show that ectopic expression of annexin A6 (AnxA6), a member of the Ca(2+) and phospholipid-binding annexins, strongly reduces pY-EGFR levels while augmenting EGFR T654 phosphorylation in EGFR overexpressing A431, head and neck and breast cancer cell lines. Reduced EGFR activation in AnxA6 expressing A431 cells is associated with reduced EGFR internalization and degradation. RNA interference (RNAi)-mediated PKCα knockdown in AnxA6 expressing A431 cells reduces T654-EGFR phosphorylation, but restores EGFR tyrosine phosphorylation, clonogenic growth and EGFR degradation. These findings correlate with AnxA6 interacting with EGFR, and elevated AnxA6 levels promoting PKCα membrane association and interaction with EGFR. Stable expression of the cytosolic N-terminal mutant AnxA6(1-175), which cannot promote PKCα membrane recruitment, does not increase T654-EGFR phosphorylation or the association of PKCα with EGFR. AnxA6 overexpression does not inhibit tyrosine phosphorylation of the T654A EGFR mutant, which cannot be phosphorylated by PKCα. Most strikingly, stable plasma membrane anchoring of AnxA6 is sufficient to recruit PKCα even in the absence of EGF or Ca(2+). In summary, AnxA6 is a new PKCα scaffold to promote PKCα-mediated EGFR inactivation through increased membrane targeting of PKCα and EGFR/PKCα complex formation.

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Overexpression of epidermal growth factor receptor (EGFR) is associated with enhanced activation of wild-type (hyperactive) Ras in breast cancer. Little is known about the regulation of Ras inactivation and GTPase-activating proteins (GAPs), such as p120GAP, in cells with hyperactive Ras. Recently, we showed that in EGFR-overexpressing A431 cells, which lack endogenous Annexin A6 (AnxA6), ectopic expression of AnxA6 stimulates membrane recruitment of p120GAP to modulate Ras signalling. We now demonstrate that, AnxA6 is downregulated in a number of EGFR-overexpressing and estrogen receptor (ER)-negative breast cancer cells. In these cells, AnxA6 overexpression promotes Ca(2+)- and EGF-inducible membrane targeting of p120GAP. In ER-negative MDA-MB-436 cells, overexpression of p120GAP, but not CAPRI or a p120GAP mutant lacking the AnxA6-binding domain inhibits Ras/MAPK activity. AnxA6 knockdown in MDA-MB-436 increases Ras activity and cell proliferation in anchorage-independent growth assays. Furthermore, AnxA6 co-immunoprecipitates with H-Ras in a Ca(2+)- and EGF-inducible manner and fluorescence resonance energy transfer (FRET) microscopy confirmed that AnxA6 is in close proximity of active (G12V), but not inactive (S17N) H-Ras. Thus, association of AnxA6 with H-Ras-containing protein complexes may contribute to regulate p120GAP/Ras assembly in EGFR-overexpressing and ER-negative breast cancer cells.

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Introducción. Es necesario tener mayor información sobre la medida de la presión arterial (PA) en el domicilio de los pacientes diagnosticados de hipertensión arterial (HTA), lo que incluye considerar el registro por personas ajenas a los propios pacientes. El objetivo de este estudio fue analizar las diferencias de PA en domicilio según se mida ésta por el propio paciente o por un familiar. Material y métodos. Estudio transversal y multicéntrico realizado en Atención Primaria en una muestra consecutiva de pacientes hipertensos mayores de 17 años tratados con dieta o con fármacos antihipertensivos al menos desde 6 semanas antes de su inclusión. Los pacientes y sus familiares fueron entrenados en la automedida de PA (AMPA) con un monitor electrónico validado para realizar medidas en su domicilio durante 5 días de la misma semana. Los días primero, tercero y quinto la medición la realizaba el propio paciente y los días segundo y cuarto un familiar. Cada día se midió la PA por la mañana y por la noche (promedio de dos tomas separadas 5 minutos). Para el análisis de los datos se excluyeron las medidas del primer día. Resultados. Se incluyeron 243 pacientes (53,8 por ciento mujeres) con una edad media (DE) de 58,6 (12,9) años. Los valores medios de la PA sistólica (PAS) registrados por los pacientes fueron de 137,9 ñ 17,4 mmHg y los registrados por los familiares de 137,9ñ16,9 mmHg (p=0,953). Los valores medios de PA diastólica (PAD) registrados por los pacientes fueron de 82,7ñ9,1 mmHg y los registrados por los familiares de 82,3 ñ 9,1 mmHg (p = 0,095). No se encontraron diferencias cuando se compararon las medidas tomadas por un familiar o por el paciente en cada sexo, diabéticos, obesos, fumadores, hipercolesterolémicos, pacientes con antecedentes de enfermedad cardiovascular o tratamiento con o sin fármacos antihipertensivos. Conclusiones. En pacientes hipertensos de Atención Primaria entrenados para realizar AMPA los valores de la PA obtenidos en el domicilio por los propios pacientes no son diferentes a los registrados por los familiares (AU)

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OBJECTIVES: To identify features of health care centers valued by health care workers as positive, to group features into dimensions, and to determine their relative importance. DESIGN: Qualitative phase: focus groups and content analysis. Quantitative phase: survey with a questionnaire developed from the features identified in the qualitative phase. SETTING: Primary care services in Reus and Tarragona (Catalonia, northeastern Spain). PARTICIPANTS: Managers, medical care providers and admissions staff. A total of 33 workers took part in focus groups, and 136 questionnaires were distributed for the survey, with a 78.6% response rate. MAIN MEASURES: Identification by focus groups of the features to be evaluated. Features were grouped into dimensions at different levels by content analysis. Survey to determine the relative importance of different features. RESULTS: We identified 133 features to be evaluated by workers: 36 related with structural features of the center (architecture, staffing and equipment), 33 with organization (accessibility, team functioning), 23 with workers (knowledge and attitudes) 20 with the services provided (needs and information management, care services provided) and 21 with management. The most highly valued dimensions were workers´ attitudes and management. CONCLUSIONS: Relations with patients and colleagues, and management issues, were valued most highly by workers. Some problematic features such as shared decision-making, team work and minority cultures revealed different levels of awareness and sensitivity within the health care system.

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OBJECTIVES: To identify the factors valued by users of health centres; to weigh the relative importance of each factor. DESIGN: Qualitative stage (4 focus groups) to identify the factors valued. Quantitative stage (questionnaire to 225 people) to weigh their relative importance. SETTING: Primary care. PARTICIPANTS: Citizens from middle-high and middle-low social classes, urban, rural and over 65, were chosen through key informants for their interest in the health services. They were recruited with the assistance of various residents' associations and town councils. METHOD: The factors valued were identified through focus groups and classified in categories. Their relative importance was weighed through a questionnaire and a factorial analysis to identify the main components was run. RESULTS: 60 factors that could be valued by patients were identified. Eight of these referred to the centre and concrete assets, nine to organisation and acessibility, 18 to relationship with the health professionals, and 25 to the services available. The most highly valued factor was: "The centre has sufficient material available for cures, minor surgery, bandages, etc." The factorial analysis confirmed the categories established. Organisation and accessibility, and relationship with professionals were the most highly valued dimensions. CONCLUSIONS: The combination of qualitative and quantitative methods seems very fitting for this kind of study. Although many of the factors were to be expected, other little-expected ones emerged. In addition, users seem to value certain factors in a different way from how the professionals do.

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Objetivos. Identificar los aspectos que valoran los pacientes en los centros de salud. Ponderar la importancia relativa de cada uno de ellos. Diseño. Fase cualitativa (4 grupos focales) para identificar los aspectos que se valoran. Fase cuantitativa (encuesta a 225 ciudadanos) para ponderar su importancia relativa. Emplazamiento. Atención primaria. Participantes. Ciudadanos de clase social media-alta, media-baja, urbanos, rurales y mayores de 65 años, seleccionados a través de informantes clave por su interés en los servicios sanitarios. Se reclutaron con la colaboración de diferentes asociaciones de vecinos y ayuntamientos. Método. Mediante grupos focales se identificaron los aspectos que se valoran, y se clasificaron en categorías. Mediante encuesta se ponderó la importancia relativa de los mismos y se realizó un análisis factorial para identificar los componentes principales. Resultados. Se identificaron 60 aspectos valorables por los pacientes. De ellos, 8 se referían al centro y eran tangibles, 9 a organización y accesibilidad, 18 a relación con los profesionales y 25 a servicios disponibles. El aspecto más valorado fue: "el centro dispone de suficiente material para curas, pequeña cirugía, vendajes, etc.". El análisis factorial confirmó las categorías que se habían establecido. La organización y accesibilidad y las relaciones con los profesionales parecen ser las dimensiones más valoradas. Conclusiones. La combinación de métodos cualitativos y cuantitativos parece muy adecuada para este tipo de estudios. Aunque muchos de los aspectos eran de esperar, aparecen otros poco previsibles. Además, los clientes parecen valorar ciertos aspectos de manera distinta a como lo harían los profesionales (AU)

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La transmisión del virus de la inmunodeficiencia humana (VIH), el virus de la hepatitis B (VHB) o el virus de la hepatitis C (VHC), desde un paciente portador a un trabajador sanitario, puede ocurrir a través de pinchazos accidentales con agujas o heridas con instrumentos cortantes. Aunque poco frecuente, la trascendencia médica y legal que una exposición ocupacional puede tener para el personal sanitario es importante. Dado el riesgo de transmisión de enfermedades infecto-contagiosas de elevada morbimortalidad, y la necesidad de tener perfectamente establecida una secuencia de actuación, hacen que estas recomendaciones de profilaxis postexposición deban ser conocidas y estar al alcance de todos los profesionales sanitarios que realicen una labor asistencial. Con este fin realizamos esta revisión y puesta al día de la "actitud a seguir en caso de accidente biológico", primando la practicidad de aplicación dentro de la amplitud que un tema tan interesante conlleva. (AU)

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The net absorption of amino acids (AA) in young pigs fed a barley-based control diet (C) and diets where barley was replaced by 200 g/kg fresh weight of dried lucerne (Medicago sativa; L20), white clover (Trifolium repens; W20) or perennial ryegrass (Lolium perenne; PR20) meal was studied. Castrated male pigs were fitted with permanent catheters in the hepatic portal vein and mesenteric artery, and the hepatic portal net absorption of AA was estimated from the porto-arterial plasma concentration differences and the hepatic portal-vein blood flow. In general, the essential AA (EAA) concentrations in the hepatic portal vein reached peak levels 90 min after feeding and thereafter exhibited a transient decline. Maximum porto-arterial differences were reached between 1 and 3 h postprandially for most of the AA. The cumulative net absorption of non-essential AA (NEAA) and EAA did not differ significantly between the barley-based diet and diets W20 and PR20. Due to a lower intake of AA on diet L20, the cumulative net absorption of NEAA and EAA was significantly (P < 0.05) lower than diet C. With the exceptions of the EAA arginine, cystine and valine, and the NEAA glutamic acid + glutamine and glycine, there were no significant differences in the absorption coefficients for the EAA and NEAA between the diets. In addition, the pattern of the total EAA in the mixture absorbed postprandially did not differ significantly between the diets. The present study gives support to the contention that the replacement of barley AA with forage meal AA in a barley-based diet for growing pigs should be expected to result in minor differences in the net portal flux of AA.

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Two experiments were performed with post-valve T-cannulated growing pigs, using five animals in each experiment in a change-over design to evaluate the effect of inclusion of four different dried forage meals on ileal crude protein (CP) and amino acid (AA) digestibilities. The control diets (C1 and C2) were barley-based and the experimental diets were formulated by replacing the barley with 100 or 200 g/kg of either lucerne (Medicago sativa) or white clover (Trifolium repens) meal in Expt 1 and red clover (Trifolium pratense) or perennial ryegrass (Lolium perenne) meal in Expt 2. A decrease (P < 0.05) in the apparent ileal digestibility of CP and most of the essential and nonessential AA was found with the inclusion of luceme, white clover and perennial ryegrass meal in the barley-based diets. When red clover meal was included, only the apparent ileal digestibilities of CP, leucine, phenylalanine, tyrosine and glutamic acid were found to decrease (P < 0.05). The estimated apparent ileal digestibilities of most essential AA in the forage meals were lower than in the barley-based diets. The ileal flow of glucosamine and ornithine was found to increase (P < 0.05) with increasing proportion of fibre in the diet, suggesting an increase in endogenous N secretions and small-intestinal microbial activity. With the minor changes found for ileal essential AA digestibilities with forage meal inclusion in the diet the present data confirm the potential of forage meals as a source of protein in pig diets.

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A high-performance liquid chromatographic method for measuring amino acids in pig plasma has been developed by using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate as a precolumn derivatization reagent. With the method presented here it was possible to separate 24 amino acids in pig plasma within one single run in 45 min, while only 18 amino acids were properly separated with the original AccQ.Tag conditions used for analysis of hydrolysate samples. The recovery was above 90% for most amino acids, and the mean coefficient of variation of the retention times below 0.30%. The within- and between-assay reproducibility for the determination of plasma amino acids showed C.V.s below 2.2% and 4.5%, respectively, for most amino acids analyzed. In the present work, most of the plasma amino acids were assayed with high sensitivity, accuracy and good reproducibility in a relatively short time and on very small amounts of sample.

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Young pigs were fed diets to which 0, 2.5, or 5 mg/kg of purified nivalenol (NIV) had been added. The exposure continued for 3 weeks without any signs of feed refusal, vomiting, or change in clinical appearance, and there were no changes in body or organ weights due to the exposure. However, the concluding macroscopic examination revealed gastrointestinal erosions and signs of nephropathy in most of the exposed pigs. There were no differences in total or differential blood leukocyte counts between control and exposed pigs in blood samples collected after 0, 1, or 3 weeks, nor in the number of thymocytes at the end of the trial. Spleen cell numbers showed a dose-dependent decrease after 3 weeks of exposure that was statistically different from controls in pigs exposed to 5 mg NIV/kg. Flow cytometric analysis of lymphocytes revealed decreased numbers of both the CD4+ and the CD8+ subpopulations in the spleen at this point in time, reflecting the lower numbers of splenocytes; but no proportional changes were seen. In blood, exposure to NIV caused a transient decrease in the proportion of CD4+ cells after 1 week of exposure. Analysis of IgG and IgA in plasma showed a time-dependent tendency of increasing plasma concentrations of IgA and decreasing concentrations of IgG in the 2.5 mg/kg group, but differences in Ig levels between experimental groups and controls were not observed at any time. No differences were seen in the mitogen-induced proliferation by lymphocytes from blood, spleen, or thymus. In conclusion, exposure of young pigs to NIV in the diet caused pathological alterations in the kidneys and gastrointestinal tract and reduced the number of splenocytes. The results also indicated that exposure to NIV caused a time-dependent increase in IgA production in the 2.5 mg/kg group.

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