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This work analyzes the evolution of the large shifting dune included in the Corrubedo Natural Park from 1956 until the present day. The analysis was carried out using aerial images, orthophotographs, topographic surveys and LiDAR (Light Detection and Ranging) data. Variations were analyzed in terms of four different aspects: evolution of pathways in each period, changes in the position of the mobile dune front and the degree of vegetation cover, all between 1956 and 2017; and variations in elevation and volume of the dune system between 2001 and 2015. To analyze these aspects, geospatial and geostatistical techniques were employed, which revealed that the dune front had undergone two different phases: one until the 1980s, with a mean seaward advance of 32 m and another one between the 1980 s and 2017, when the front prograded to the continent, with an approximate mean advance of 82 m. Loss of volume, related to the expansion of the mobile dune towards the north, was confirmed in this sector. It is evident that these changes are closely linked to anthropic influence, due to sand extraction until the early 1990s and, more recently, due to an increase in the number of visitors to the Natural Park. The results obtained highlight the need to carry out detailed studies to understand the evolution of this system and to prevent further damage in the future. Moreover, based on these analyses, a strategy to improve coastal and environmental management in the Corrubedo Natural Park could be designed. [ABSTRACT FROM AUTHOR]

The Natura 2000 network is an ambitious European project aimed at nature conservation. Nevertheless, the identification and delimitation of habitats is a complex task and simultaneously essential for correct ecosystem management. In this study we compared the current habitat delimitation and designation and the results produced by Geographic Information Systems (GIS) and geochemical proxies for the categorization of four coastal lakes in Galicia (NW Iberian Peninsula). The findings reveal important errors in the delimitation/designation. The first error is the designation of all four lakes as Coastal lagoons (habitat 1150), when geochemical data indicate that two of these lakes were always freshwater lakes and should consequently be classified as Natural eutrophic lakes (habitat 3150). Another error is of conceptual origin, because the lakes comprise a unique functional system composing of different environmental units (e.g., open water or aquatic vegetation). Subdivision into different habitats is therefore meaningless for units of negligible surface area. In addition, the designation of some habitats is very dubious according to the available data. Finally, notable changes in relation to the temporal changes of wetlands were observed. Thus, the area occupied by aquatic macrophytes increased greatly at the expense of open waters, and the increase was also reflected in the alluvial forest. This last finding indicates the importance of updating the state of Natura 2000 network in Galicia to improve habitat management. [ABSTRACT FROM AUTHOR]

Due to the limited number of studies on phytoremediation using native tree species in tropical soils, the aim was to identify new phytoremediator species from tropical climate with the purpose of promoting an increase in the diversity of tropical native trees used in phytoremediation projects. Seven native tree species from Brazil were selected: Cedrela fissilis, Handroanthus serratifolius, Copaifera langsdorffii, Hymenaea courbaril, Mimosa caesalpiniifolia, Cecropia sp. and Myracrodruon urundeuva. Seedlings of these species were planted in pots with an unpolluted Arenosol, and then spiked with 60, 100 and 500 mg kg−1 Cu. Height and stem diameters were measured over 60 days. Biomass and total Cu concentration were determined in leaves, stem and roots. Copper in bulk soils and rhizospheres was analyzed by a sequential extraction method. All species accumulated high concentration of Cu in roots (>300 mg kg−1), so they could be used as phytostabilizators for this metal. Copper mobilization increased in the rhizospheres, but it was mostly absorbed by roots. Cecropia sp., M. urundeuva and C. langsdorffii are hyperaccumulators of Cu (>300 mg kg−1 in shoots), so they are potential phytoextractor species. This study evidence the potential of seven tree species native from tropical regions for phytostabilizing copper-polluted soils. [ABSTRACT FROM AUTHOR]

The minerals of the clay fraction in estuarine plains are mainly detrital, being a mixture of marine and continental sediments, but can also be authigenic. Because of the importance of mangrove ecosystems in tropical estuarine areas and the relatively few existing studies of the mineralogical composition of soils in these environments, the aim of this study was to determine the mineralogical assemblage and identify potential contrasts along the coast of the State of São Paulo. Soils from 11 mangroves distributed along the coastal plain of the State of São Paulo were sampled at depths of 0 to 20 and 60 to 80 cm, and samples of suspended sediments from the Ribeira do Iguape River were collected for analysis. Mineralogical analyses were performed on the clay and silt fractions by x-ray diffraction (XRD) and transmission electron microscopy, and fresh soil samples were analyzed by scanning electron microscopy-energy dispersive spectrometry and suspended sediments by XRD. The silt fraction contained quartz, feldspars, gibbsite, kaolinite, illite, and vermiculite, and the clay fraction contained smectite, kaolinite, illite, gibbsite, quartz, and feldspars. Locally, vermiculite, biotite, anatase, halloysite, and goethite may occur because of recent transport of sediments to the system. Pyrite was identified in fresh samples. The allochthonous minerals found either were terrestrial and transported by rivers or had originated from the continental platform by past transgressive events. We suggest that the neoformation of smectite and kaolinite occurs in mangrove soils. Different geomorphological settings along the São Paulo coast appear to regulate mineral distribution in mangrove soils. [ABSTRACT FROM AUTHOR]

Pore-water and solid-phase analysis was undertaken to study the effects of different environmental conditions on redox processes in mangrove soils on the southern coast of Brazil. Three Rhizophora mangle (L.) mangrove forests were studied in different physiographic positions-riverine, fringe, and basin forest-and substrate compositions. Our results indicate different geochemical conditions in soils from different physiographic positions. In the fringe soils, the low acid-volatile sulfide and pyrite Fe contents, associated with high values of Fe2+ in pore water, indicate oxic and suboxic conditions in surface layers (0-10 cm). Below this depth, anoxic conditions prevail and sulfate reduction becomes the dominant process of organic matter decay, as indicated by higher concentrations of dissolved HS and pyrite Fe. In the basin forest, long periods of tidal flooding and low rates of litter export maintained anoxic conditions and high organic matter contents, necessary for anoxic respiration to take place, as shown by the low Fe2+ and HS- concentrations in pore water, along with high degree of Fe pyritization values and high concentrations of pyrite Fe. In the riverine soils, the lowest concentrations of pyrite Fe and the highest concentrations of HSin pore water were obtained in response to low availability of reactive Fe (0-10cm, 31.8 ± 8.0 mmol kg-1; 20-30 cm, 43.2 ± 32.3 mmol kg-1) due to its sandy texture, which limits pyrite synthesis. Our results indicate that the participation and intensity of each process may vary within different physiographic positions because of the effects on the frequency and duration of tidal flooding and soil composition. Our results also show that R. mangle is present on substrates with different geochemical conditions (oxic, suboxic, and anoxic). [ABSTRACT FROM AUTHOR]

Concentrations of Fe, Mn, Ni, Cu, Cr and Zn in their total, silicate, organic, reactive and pyrite fractions were determined in soils collected from the Ortigueira saltmarshes (Esteiro, Ladrido and Mera, NWIberian Peninsula), from sediments of the Landoi and Esteiro Rivers,and from sludge generated by a nearby dunite mine. The Esteiro saltmarsh presented clear enrichments of the four metals studied (first 10cm), especially of Ni and Cr, whose concentrations were among the highest. It is proposed that the elevated Cr and Ni levels found in theEsteiro saltmarsh were derived from recent contributions of the mine, which are partially discharged into the Landoi River. Total Cu and Zn concentrations were lower than the corresponding ones for Cr and Ni. Under suboxic conditions, Ni, Cr, Cu and Zn were mainly associatedwith the reactive fraction. Under anoxic conditions, Cu and Ni were associated mainly with the pyrite phase. Pyritic Zn and Cr concentrations were relatively low and similar in all three saltmarshes; however, where anoxic/sulfidic conditions prevailed these two metals were mainly associated with the reactive and organic fractions. [ABSTRACT FROM AUTHOR]

The mobilisation of potentially harmful chemical constituents in wildfire ash can be a major consequence of wildfires, posing widespread societal risks. Knowledge of wildfire ash chemical composition is crucial to anticipate and mitigate these risks. Here we present a comprehensive dataset on the chemical characteristics of a wide range of wildfire ashes (42 types and a total of 148 samples) from wildfires across the globe and examine their potential societal and environmental implications. An extensive review of studies analysing chemical composition in ash was also performed to complement and compare our ash dataset. Most ashes in our dataset had an alkaline reaction (mean pH 8.8, ranging between 6 and 11.2). Important constituents of wildfire ash were organic carbon (mean: 204 g kg -1 ), calcium, aluminium, and iron (mean: 47.9, 17.9 and 17.1 g kg -1 ). Mean nitrogen and phosphorus ranged between 1 and 25 g kg -1 , and between 0.2 and 9.9 g kg -1 , respectively. The largest concentrations of metals of concern for human and ecosystem health were observed for manganese (mean: 1488 mg kg -1 ; three ecosystems > 1000 mg kg -1 ), zinc (mean: 181 mg kg -1 ; two ecosystems > 500 mg kg -1 ) and lead (mean: 66.9 mg kg -1 ; two ecosystems > 200 mg kg -1 ). Burn severity and sampling timing were key factors influencing ash chemical characteristics like pH, carbon and nitrogen concentrations. The highest readily dissolvable fractions (as a % of ash dry weight) in water were observed for sodium (18 %) and magnesium (11.4 %). Although concentrations of elements of concern were very close to, or exceeded international contamination standards in some ashes, the actual effect of ash will depend on factors like ash loads and the dilution into environmental matrices such as water, soil and sediment. Our approach can serve as an initial methodological standardisation of wildfire ash sampling and chemical analysis protocols., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Seabird colonies exert a strong influence on coastal ecosystems, increasing soil nitrogen bioavailability and modifying plant communities. Previous studies have evidenced that increased N in soils leads to changes in plant cell wall composition; however, this effect has not been assessed in seabird colonies. The main objective of this study was to determine the influence of seabird colonies on nitrogen, cellulose and lignin content in cell walls. For this purpose, analyses were performed on droppings, soils and three native plant species (Armeria pubigera, Armeria pungens and Corema album) growing in yellow-legged gull colonies. The results showed that N excreted by yellow-legged gull is assimilated by plants, increases N content in plant tissues and reduces cellulose and lignin synthesis, therefore potentially altering plant resistance against phytoparasites., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Seabirds form large colonies during the reproductive period, producing substantial changes in coastal ecosystems. The present study quantifies the amount of N and P deposited in colonies of yellow-legged gull (Larus michahellis) in the Atlantic Islands of Galicia National Park (AINP). Based on the composition of droppings, the amount of total N (TN), total P (TP) and bioavailable P (Pbio) deposited directly on the area occupied by the colony was determined. In addition, the amount of NH 3 released into the atmosphere was also estimated by applying a bioenergetic model. The results indicated that 5.35 t total N, 3.35 t total P and 1.24 t bioavailable P are deposited in the colony annually. The archipelagos that received the greatest amount of nutrients were the Cíes Islands (2.37 t TN y -1 , 1.48 t TP y -1 , 0.55 t Pbio y -1 ), Sálvora (1.94 t TN y -1 , 1.22 t TP y -1 , 0.55 t Pbio y -1 ) and Ons (1.04 t TN y -1 , 0.65 TP y -1 , 0.24 t Pbio y -1 ). Rainwater from the colonies showed higher values of nutrients than in the control plot, possibly also due to gull influence. Therefore, the yellow-legged gull colony seems to be the most important source of nutrients at a local level, exerting a clear influence on the N and P cycles in this National Park. Another aspect worth taking into consideration is that increased N and P bioavailability may have a negative effect on the conservation of rare or threatened habitats and species by promoting the expansion of non-native ruderal species., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The Ría de Ortigueira is an environmentally well conserved; however, the sediments show high concentrations of toxic elements. In some zones, the concentrations of Ni (60-1080 mg kg -1 ) and Cr (9-567 mg kg -1 ) were extremely high, while the concentrations of other toxic elements were within normal ranges. PCA revealed that metal enrichment was due to dumping of waste sludge from a peridotite mine. The study of marine currents showed that the exit of the contaminated waste towards the external zone is restricted by the low energy of the residual currents, and the sludge therefore remains trapped in the internal zones. The potential ecological risk was moderate for all areas of the ría, reaching high values close to the mouth of the river Landoi. Finally, geochemical fractioning showed that most of the metals are associated with Fe oxyhydroxides which can become unstable and release adsorbed or coprecipitated metals, especially Ni., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Technosols created to reclaim degraded soils is a promising solution that needs further research. The objectives of the study were: i) to create a Technosol with a very high capacity to immobilize copper from mining, ii) to assess the capacity of the Technosol to immobilize copper after planting two tropical native tree species, and iii) to analyse the capacity of the native trees for extracting copper from polluted soils. Myracrodruon urundeuva (aroeira) and Cedrela fissilis (pink cedar) were planted in pots with Technosol spiked with copper at concentrations of 125, 1525 and 3050 mg Cu kg -1 . Height and stem diameter were measured over 90 days. Biomass and Cu concentration in leaves, stem and roots were determined. Copper was analysed in soils by sequential extraction, as well as in leached water. The Technosol showed a very high capacity to immobilize copper, since 60-80% of the added copper was strongly retained in the soil, mainly by bentonite and carbonates. The Technosol with trees showed the same capacity to immobilize copper as the control, since concentration in shoots was higher than 300 mg Cu kg -1 and concentration in roots was even higher. These results show that Technosol and both species are useful tools to immobilize copper in polluted soils. Further studies are necessary to determine the total capacity of these trees to immobilize and/or extract copper in the long term and under field conditions., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Marine-derived nutrients are known accumulate in seabird breeding colonies due to the deposition of nutrient-rich biological materials, thus greatly altering the functioning and dynamics of these terrestrial ecosystems. Here we present the results of a sampling survey carried out during three years in yellow-legged gull colonies in the Atlantic Islands of Galicia National Park (NW Spain) with the aim of evaluating the influence of the colonies on the accumulation of trace elements, including micronutrients (Cu, Zn, Se, Co, Mo, Ni) and toxic elements (Cr, Cd, Hg, Pb, As, Ag), in the surrounding environments. For this purpose, we analysed samples of biological materials produced by the seabirds (pellets, excrement, feathers, eggs) and of soil, plants and inland water from several different subcolonies and control zones without seabirds. The concentrations of most of the elements were higher in excrement and pellets (mean values: Zn: 152, As: 50 mg kg -1 , Cd: 6, Co: 5 mg kg -1 ) than in feathers and eggs. The flow of trace elements into the breeding colonies, considering only the excrement, revealed a very high level of trace element deposition for a supposedly pristine environment (Zn: 2667, Cd: 70, Cu: 315, As: 64 g ha -1 ). The total concentrations of trace elements in soil were consistent with the long-term impact of the seabirds. Thus, the values in areas which this impact was greatest were significantly higher than in the control zones, particularly considering the most labile geochemical fractions of the soil. The concentrations of some elements (i.e. Co, As, Cd) were also higher in the inland waters in the colonies than in control zones. Finally, the concentration of trace elements in plants varied depending on the species and element considered., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Seabird colonies drastically transform the sites that they inhabit. Although the influence of seabirds on nutrient cycling has been investigated in numerous studies, the effects on trace elements has scarcely been considered. In this study, we determined the total contents of 9 trace elements in biomaterials (excrement, pellets, feathers and eggs) and soils in relation to the presence the Yellow-legged gull Larus michahellis. The concentrations of Zn, Cu and As were particularly high in the pellets and excrement. The total contents of the trace elements were significantly higher in the soils in the sub-colonies in which Yellow-legged gulls predominate than in soil from the control zone (with no gulls). The difference was even higher for the most reactive geochemical fractions. We observed that the oxidizable fraction was the most relevant fraction for almost all trace elements, indicating the importance of organic matter in trace element retention in sandy soils., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Mangrove forests play an important role in biogeochemical cycle of C, storing large amounts of organic carbon. However, these functions can be controlled by the high spatial heterogeneity of these intertidal environments. In this study were performed an intensive sampling characterizing mangrove soils under different type of vegetation (Rhizophora/Avicennia/dead mangrove) in the Venezuelan coast. The soils were anoxic, with a pH~7; however other soil parameters varied widely (e.g., clay, organic carbon). Dead mangrove area showed a significant lower amounts of total organic carbon (TOC) (6.8±2.2%), in comparison to the well-preserved mangrove of Avicennia or Rhizophora (TOC=17-20%). Our results indicate that 56% of the TOC was lost within a period of 10years and we estimate that 11,219kgm -2 of CO 2 was emitted as a result of the mangrove death. These results represent an average emission rate of 11.2±19.17tCO 2 ha -1 y -1 ., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Geogenic arsenic (As) can accumulate and reach high concentrations in rice grains, thus representing a potential threat to human health. Ecuador is one of the main consumers of rice in South America. However, there is no information available about the concentrations of As in rice agrosystems, although some water bodies are known to contain high levels of the element. We carried out extensive sampling of water, soil, rice plants and commercial rice (obtained from local markets). Water samples were analysed to determine physico-chemical properties and concentrations of dissolved arsenic. Soil samples were analysed to determine total organic C, texture, total Fe and amorphous Fe oxyhydroxides (Fe Ox ), total arsenic (tAs) and the bioavailable fraction (As Me ). The different plant parts were analysed separately to determine total (tAs), inorganic (iAs) and organic arsenic (oAs). Low concentrations of arsenic were found in samples of water (generally <10μgl -1 ) and soil (4.48±3mgkg -1 ). The tAs in the rice grains was within the usual range (0.042-0.125mgkg -1 dry weight, d.w.) and was significantly lower than in leaves (0.123-0.286mgkg -1 d.w.) and stems (0.091-0.201mgkg -1 d.w.). The Fe Ox and tAs and also As Me in flood water were negatively correlated with tAs in the plants. However, the concentrations of As in stems and leaves were linearly correlated with tAs in the soil and flood water. The relationship between tAs and arsenic in the grain fitted a logarithmic function, as did that between tAs in the grain and the stem. The findings seem to indicate that high concentrations of arsenic in the environment (soil or water) or in the rice stem do not necessarily imply accumulation of the element in the grain. The iAs form was dominant (>80%) in all parts of the rice plants., (Copyright © 2016 Elsevier B.V. All rights reserved.)

During the period 1980-2000, the yellow-legged gull population underwent exponential growth due to an increase in the availability of anthropogenic food resources. The aim of this study was to highlight the effect of the gull colonies on the P soil cycle and the associated effects on coastal ecosystems. Samples of soil, water and faecal material were collected in a colony of yellow-legged gulls (Cíes Islands) and in a control area. Four sampling plots were installed in the study areas, and samples were collected in summer and winter in 1997 and 2011. Sample analysis included soil characterization and determination of the total P content (TP), bioavailable-P and fractionated-P forms in the soils and faecal material. The (31)P NMR technique was also used to determine organic P forms. Clear differences between the gull colony soils and the control soil were observed. The TP was 3 times higher in the gull colony soil, and the bioavailable P was 30 times higher than in the control soil. The P forms present at highest concentrations in the faecal material (P-apatite, P-residual and P-humic acid) were also present at high concentrations in the colony soil. The absence of any seasonal or annual differences in P concentration indicates that the P has remained stable in the soil over time, regardless of the changes in the gull population density. The degree of P saturation indicated that soils are saturated with P due to the low concentration of Fe/Al-hydroxides, which is consistent with a high P concentration in the run-off from the colonies. The P output from the colony soils to coastal waters may cause eutrophication of a nearby lagoon and the disappearance of a Zostera marina seagrass meadow. Similarly, the enrichment of P concentration in dune system of Muxieiro may induce irreversible changes in the plant communities., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The trace elements present at highest concentrations were Cr and Zn, which probably originated from the dumping of effluent from a tanning factory. High proportions of these two elements were associated with the residual fraction. Biodeposits and sediments showed high concentrations of Cd and Pb in the reactive fraction, with a high proportion of the concentration in the reactive fraction being associated with carbonates. Nickel showed a higher degree of pyritization than the previous elements, although most of the Ni was associated with the residual and reactive fractions. Arsenic, Hg and Cu showed high degrees of pyritization, particularly below a depth of 5 cm. The results demonstrate that those elements with a high degree of pyritization may be released into the water through oxidation of the metal sulphides that they form when in suspension in oxic sea water, with the subsequent risk of increased bioavailability to benthic fauna.

The reported prevalence rate of anti-hepatitis C virus (HCV) antibodies in patients with oral lichen planus shows wide geographical variation and ranges from 0 to 65%. Certain characteristic clinical features have been attributed to oral lichen planus associated to HCV infection. The purpose of this investigation has been to assess hypothetical clinical differences, as well as differences in the intensity of the subepithelial inflammatory infiltrate between oral lichen planus-HCV +ve patients and oral lichen planus-HCV -ve patients. A total of sixty-two patients entered the study. Their mean age was 63.5 +/- 14.49 years, and 48.4% of them were men and 51.6% women. Patients were classified according to their serum HCV positivity. Age, sex, clinical presentation (reticular or atrophic-erosive), extension of the lesions, location of the lesions, number of locations affected, intensity of the inflammatory infiltrate and Candida albicans colonization were recorded for each patient. Reticular lichen planus was the most frequent clinical presentation in both HCV +ve (57.1%) and HCV -ve patients (63.6%). C. albicans colonization ranged from 42.8% in HCV +ve and 41.7% in HCV -ve patients. HCV + ve patients showed certain oral locations more frequently affected than HCV -ve ones: lip mucosa, 28.6% versus 7.3%; tongue, 57.1% versus 29.1%; and gingiva, 71.4% versus 23.6%. The number of affected intraoral locations was higher in HCV +ve patients (71.4%) than among HCV -ve ones (20.4%; chi2 = 8.34; P < 0.011). No statistically significant differences could be established in terms of density of subepithelial inflammatory infiltrate between the groups. Our results reinforce the need for liver examination in all patients with oral lichen planus, particularly those showing lesions on the gingiva with multiple intraoral locations affected, as no pathological differences could be identified between HCV + ve and HCV -ve patients.

The relation between the potassium concentration in the vitreous humor, [K+], and the postmortem interval has been studied by several authors. Many formulae are available and they are based on a correlation test and linear regression using the PMI as the independent variable and [K+] as the dependent variable. The estimation of the confidence interval is based on this formulation. However, in forensic work, it is necessary to use [K+] as the independent variable to estimate the PMI. Although all authors have obtained the PMI by direct use of these formulae, it is, nevertheless, an inexact approach, which leads to false estimations. What is required is to change the variables, obtaining a new equation in which [K+] is considered as the independent variable and the PMI as the dependent. The regression line obtained from our data is [K+] = 5.35 + 0.22 PMI, by changing the variables we get PMI = 2.58[K+] - 9.30. When only nonhospital deaths are considered, the results are considerably improved. In this case, we get [K+] = 5.60 + 0.17 PMI and, consequently, PMI = 3.92[K+] - 19.04.

One of the most active topics in the growth hormone-IGF-1 field is that of the so-called growth hormone secretagogues (GHS). At a time when the isolation of GHRH had not occurred, the GHS were developed as artificial tools to release GH. The interest in these groups of compounds was rekindled when it was realized that they were not surrogates of GHRH nor were they acting through the modulation of the release of either GHRH or somatostatin. With the subsequent cloning of the specific receptor of GHS, and today of the natural ligand for that receptor, named ghrelin, it soon become clear that GHS and the GHS-receptor were part of a new physiological system involved in GH regulation. The dual control of GH secretion became a trinity. GHS releases GH when administered by any route--oral, iv, sc, and even transdermally-with a surprising potency and reproductivity. In addition, GHS when administered together with GHRH exert a synergistic action on GH secretion and that combined administration is the most potent GH releaser to date. Clinical studies have demonstrated that the GHS-GHRH administration may be considered the new "gold standard" test of GH reserve in humans, as the GH secretion so elicited is not altered by gender, adiposity, or age. The combined administration of GHRH plus GHS is able to discriminate between healthy subjects and patients with adult GH deficiency, suggesting a considerable utility in the clinical setting.

Concentrations of Fe, Mn, Ni, Cu, Cr and Zn in their total, silicate, organic, reactive and pyrite fractions were determined in soils collected from the Ortigueira saltmarshes (Esteiro, Ladrido and Mera, NW Iberian Peninsula), from sediments of the Landoi and Esteiro Rivers, and from sludge generated by a nearby dunite mine. The Esteiro saltmarsh presented clear enrichments of the four metals studied (first 10 cm), especially of Ni and Cr, whose concentrations were among the highest. It is proposed that the elevated Cr and Ni levels found in the Esteiro saltmarsh were derived from recent contributions of the mine, which are partially discharged into the Landoi River. Total Cu and Zn concentrations were lower than the corresponding ones for Cr and Ni. Under suboxic conditions, Ni, Cr, Cu and Zn were mainly associated with the reactive fraction. Under anoxic conditions, Cu and Ni were associated mainly with the pyrite phase. Pyritic Zn and Cr concentrations were relatively low and similar in all three saltmarshes; however, where anoxic-sulfidic conditions prevailed these two metals were mainly associated with the reactive and organic fractions.

Background: Withdrawal of the drug(s) that cause severe cutaneous adverse reactions is usually recommended without proof that it alters the course of those reactions., Objective: To determine whether the timing of causative drug withdrawal is related to the prognosis of patients with toxic epidermal necrolysis (TEN) or Stevens-Johnson syndrome (SJS)., Design: A 10-year observational study (January 1, 1987, through October 30, 1997) of patients admitted to a dermatological intensive care unit, using binary logistic regression analysis., Setting: A single referral unit in a university hospital., Patients: Consecutive sample of 203 patients with TEN or SJS. Exclusion criteria included causative drug undetermined, lack of information on disease evolution, the date of causative drug(s) withdrawal, or the date when the first definite sign of TEN or SJS appeared., Main Outcome Measure: Death before hospital discharge., Results: One hundred thirteen patients were included; 74 had TEN and 39 had SJS; 20 died. The drug causing TEN or SJS was withdrawn early in 64 patients and late (after the first definite sign of TEN or SJS) in 49 patients. After adjustment for confounding variables (age, maximum extent of detachment, admission year, human immunodeficiency virus status), our model showed that the earlier the causative drug was withdrawn, the better the prognosis (odds ratio, 0.69 for each day; 95% confidence interval, 0.53-0.89). Patients exposed to causative drugs with long half-lives had an increased risk of dying (odds ratio, 4.9; 95% confidence interval, 1.3-18.9). The variables did not interact., Conclusions: Prompt withdrawal of drug(s) that are suspected to cause SJS or TEN may decrease mortality. Prompt withdrawal of causative drugs should be a priority when blisters or erosions appear in the course of a drug eruption.

Antifungal susceptibility tests are influenced by a number of technical variables, including inoculum size, temperature, medium formulation and duration of incubation. In this study, we have compared the in vitro susceptibility of 20 strains de Trichophyton rubrum against clotrimazole and terbinafine, and studied the influence of incubation time on MICs of both drugs. The assay was performed by agar dilution, the medium used was Saboraud glucose agar without an antibiotic. The MIC was evaluated at 15, 30 and 45 days' incubation. The MICs ranges of terbinafine were 0.002 to 0.0975 microg/ml, 0.0975 to 0.39 microg/ml and 0.195 to 0.39 microg/ml at 15, 30 and 45 days' incubation, respectively. The MICs ranges of clotrimazole at 15, 30 and 45 days' incubation were 3.125 to 50 microg/ml. T. rubrum was markedly more susceptible to terbinafine than to clotrimazole (p<0.001). In addition, we observed that an increase of incubation time causing an increase in the MIC value of terbinafine (p<0.001), but MIC values for clotrimazole remained constant with time (p=0.464). In conclusion, the MIC is dependent on reading time and the antifungal compound.

To correct for the effect of reporting delay on incidence data relating to AIDS, three methods of estimation have been analysed: Poisson log-linear; log-linear logistic mixed regression (log-logit), and truncation. The first two methods transform the data in a contingency table. The difference between them is the hypothesis of delay stationarity, which is only assumed by the former. A correction is proposed for the first method to improve its asymptotic properties. The truncation method is based on the product-limit estimator. A simulation study was carried out to examine the behaviour (means, variances and mean squared errors) of the three methods. All were applied to data from the National Commission on AIDS (Spain), showing an improvement in reporting efficiency.