Densidad escanográfica de los senos venosos en pacientes sanos a 2600 metros sobre el nivel del mar / Computed Tomography Density of the Venous Sinuses in Healthy Patients at 2600 Meters Above Sea Level

Introducción: Existe relación entre la densidad escanográfica de las estructuras vasculares medida en unidades Hounsfield (UH) y el hematocrito, el cual se incrementa en las personas que viven a mayor altitud sobre el nivel del mar. Se ha descrito que una densidad de 70 UH es el valor límite superior de normalidad de densidad de los senos venosos en personas sin trombosis venosa que habitan a una altitud de 1.000 m s. n. m.; sin embargo, no se ha establecido esta medida en personas que habitan en altitudes geográficas mayores. En este estudio se determinó dicho valor para personas sin trombosis de senos venosos que viven a 2.600 m s. n. m. Objetivo: Este estudio tiene como propósito caracterizar la densidad normal de los senos venosos en pacientes que habitan en altitudes geográficas de 2.600 m s. n. m. Metodología: Se analizaron las densidades escanográficas de los senos venosos longitudinal superior y de los sitios de unión entre los senos transversos y senos sigmoides de 240 sujetos que habitan a 2.600 m s. n. m., quienes asistieron a la institución entre enero de 2008 y junio de 2016. Estas personas consultaron por cefalea, convulsiones, alteración del estado de conciencia o focalización neurológica. A estos pacientes se les realizó inicialmente un estudio escanográfico de cráneo simple, hemoglobina y hematocrito con diferencia no mayor a 3 días entre el estudio escanográfico y el hemograma, así como estudios confirmatorios de positividad o ausencia de trombosis de senos intracraneales mediante resonancia magnética simple o angiorresonancia. Resultados: La media de UH fue de 59,8 con un rango entre 43,2 y 74,9, para pacientes normales. Se encontró una correlación positiva de 0,49 entre el hematocrito y las UH como es ampliamente conocido en la literatura. Conclusión: El rango en UH de los pacientes sin trombosis de senos venosos es amplio y supera por 4 puntos el informado en la literatura. Esto puede ser atribuible al aumento del hematocrito en individuos que viven a 2.600 m s. n. m. Para establecer normalidad en los pacientes con valores superiores a 70 UH se sugiere tomar en cuenta la simetría de la densidad escanográfica con respecto al seno venoso contralateral, así como evaluar la morfología del borde anterior del seno venoso y la adecuada localización del ROI (Region of Interest) para medir la densidad venosa.

Introduction: There is a relationship between the intravascular density measured in Hounsfield units (HU) in computed tomography (CT) and the hematocrit levels, which increases in people who live above sea level. The expected density in venous sinuses is lower than 70 HU in healthy people living at 1000 meters above sea level. However, this measure has not been established in people living at higher geographic altitudes. In this study, this value was determined for normal people living at 2,600 meters above sea level. Objective: The purpose of this study is to characterize the normal density of the venous sinuses in patients who live at geographical altitudes of 2,600 m above sea level. Methodology: We measured the density on CT at the superior longitudinal venous sinus and at the junction between the transverse sinus and sigmoid sinus of 240 subjects living at 2600 meters above sea level from January 2008 to June 2016. These patients consulted for headache, seizures, altered state of consciousness or neurological focus. Initially, all participants had a non-enhanced CT brain, hemoglobin and hematocrit levels with a difference of no more than 3 days between the CT study and the hemogram, as well as confirmatory studies of positivity or absence of intracranial sinus thrombosis by non-enhanced MR or MRA. Results: The mean HU was 59.8 with a range between 43.2 and 74.9, for normal patients. A positive correlation of 0.49 was found between hematocrit and HU, as is widely known in the literature. Conclusion: We obtained a wide range in the HU of healthy patients compared to the values reported in other papers, and exceeds the highest value by 4 points. This may be attributable to the increased hematocrit in healthy patients living at 2,600 meters above sea level. In order to establish whether patients with venous sinus densities greater than 70 HU have venous thrombosis, our suggestion is to evaluate the symmetry of the density compared to the contralateral venous sinus, as well as to evaluate the morphology and the location of the ROI used to measure venous density.

Non-neoplastic cholangiopathies: an algorithmic approach.

Cholangiopathies are chronic diseases that affect the bile ducts, comprising a heterogeneous group of progressive and potentially fatal entities. The diagnosis of these diseases is a great challenge for radiologists because of the overlapping of their clinical, biochemical, and imaging findings. Nevertheless, identifying the precise etiology is crucial, given that the therapeutic options are distinct and influence the prognosis of the patient. The purpose of this review article is to discuss some of the non-neoplastic causes of cholangiopathies and to provide a useful diagnostic algorithm.

As colangiopatias são doenças crônicas que afetam as vias biliares, constituindo um grupo heterogêneo de doenças progressivas e potencialmente fatais. O seu diagnóstico configura um grande desafio para os radiologistas, uma vez que seus aspectos clínicos, laboratoriais e de imagem se sobrepõem. Apesar disso, a busca etiológica é crucial, tendo em vista que as opções terapêuticas são distintas e influenciam o prognóstico do paciente. O objetivo deste artigo de revisão é discutir algumas das causas não neoplásicas de colangiopatias e fornecer um algoritmo útil na abordagem diagnóstica.

Non-neoplastic cholangiopathies: an algorithmic approach / Colangiopatias não neoplásicas: uma abordagem algorítmica

Abstract Cholangiopathies are chronic diseases that affect the bile ducts, comprising a heterogeneous group of progressive and potentially fatal entities. The diagnosis of these diseases is a great challenge for radiologists because of the overlapping of their clinical, biochemical, and imaging findings. Nevertheless, identifying the precise etiology is crucial, given that the therapeutic options are distinct and influence the prognosis of the patient. The purpose of this review article is to discuss some of the non-neoplastic causes of cholangiopathies and to provide a useful diagnostic algorithm.

Resumo As colangiopatias são doenças crônicas que afetam as vias biliares, constituindo um grupo heterogêneo de doenças progressivas e potencialmente fatais. O seu diagnóstico configura um grande desafio para os radiologistas, uma vez que seus aspectos clínicos, laboratoriais e de imagem se sobrepõem. Apesar disso, a busca etiológica é crucial, tendo em vista que as opções terapêuticas são distintas e influenciam o prognóstico do paciente. O objetivo deste artigo de revisão é discutir algumas das causas não neoplásicas de colangiopatias e fornecer um algoritmo útil na abordagem diagnóstica.

Hepatic neuroendocrine neoplasm: imaging patterns.

Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors with distinct morphological and biological manifestations, the liver being the main organ affected by its metastases. However, primary hepatic involvement is quite rare. Hepatic NENs can have a variety of radiological presentation forms and can therefore mimic other lesions, making their diagnosis challenging. Nonetheless, certain imaging aspects allow NENs to be included among the main differential diagnoses of hepatic lesions and can guide the search for an extrahepatic primary site when the probable diagnosis is metastases.

As neoplasias neuroendócrinas (NNEs) são um grupo heterogêneo de tumores com manifestações morfológicas e biológicas distintas, sendo o fígado o principal órgão acometido por suas metástases. Por outro lado, o acometimento primário deste órgão é muito raro. Podem-se observar as mais diversas formas de apresentação radiológica das NNEs hepáticas primária e secundária e, em razão dessa variedade e por mimetizar outras lesões, o seu diagnóstico pode se revelar um desafio. No entanto, alguns desses aspectos permitem incluir as NNEs entre os principais diagnósticos diferenciais de lesões hepáticas e, nos casos de metástases, orientar na busca de um eventual sítio primário extra-hepático.

Hepatic neuroendocrine neoplasm: imaging patterns / Neoplasia neuroendócrina hepática: padrões de imagem

Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors with distinct morphological and biological manifestations, the liver being the main organ affected by its metastases. However, primary hepatic involvement is quite rare. Hepatic NENs can have a variety of radiological presentation forms and can therefore mimic other lesions, making their diagnosis challenging. Nonetheless, certain imaging aspects allow NENs to be included among the main differential diagnoses of hepatic lesions and can guide the search for an extrahepatic primary site when the probable diagnosis is metastases.

As neoplasias neuroendócrinas (NNEs) são um grupo heterogêneo de tumores com manifestações morfológicas e biológicas distintas, sendo o fígado o principal órgão acometido por suas metástases. Por outro lado, o acometimento primário deste órgão é muito raro. Podem-se observar as mais diversas formas de apresentação radiológica das NNEs hepáticas primária e secundária e, em razão dessa variedade e por mimetizar outras lesões, o seu diagnóstico pode se revelar um desafio. No entanto, alguns desses aspectos permitem incluir as NNEs entre os principais diagnósticos diferenciais de lesões hepáticas e, nos casos de metástases, orientar na busca de um eventual sítio primário extra-hepático.

Clinical management and outcome of patients with advanced NSCLC carrying EGFR mutations in Spain.

BACKGROUND: Although the benefit of first-line epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitors (TKIs) over chemotherapy has been demonstrated in several clinical trials, data from clinical practice is lacking and the optimal EGFR TKI to be used remains unclear. This study aims to assess the real-life diagnostic and clinical management and outcome of patients with advanced non-small-cell lung cancer (NSCLC) carrying EGFR mutations in Spain. METHODS: All consecutive patients recently diagnosed with advanced or metastatic NSCLC from April 2010 to December 2011 in 18 Spanish hospitals and carrying EGFR mutations were retrospectively evaluated. RESULTS: Between March and November 2013, a total of 187 patients were enrolled (98.3% Caucasian, 61.9% female, 54.9% never-smokers, 89.0% adenocarcinoma). Mutation testing was mainly performed on biopsy tumour tissue specimens (69.0%) using a qPCR-based test (90%) (47.0% Therascreen EGFR PCR Kit). Common sensitising mutations were detected in 79.8% of patients: 57.1% had exon 19 deletions and 22.6% exon 21 L858R point mutations. The vast majority of patients received first-line therapy (n = 168; 92.8%). EGFR TKIs were the most commonly used first-line treatment (81.5%), while chemotherapy was more frequently administered as a second- and third-line option (51.9% and 56.0%, respectively). Of 141 patients who experienced disease progression, 79 (56.0%) received second-line treatment. After disease progression on first-line TKIs (n = 112), 33.9% received chemotherapy, 8.9% chemotherapy and a TKI, and 9.8% continued TKI therapy. Most patients received first-line gefitinib (83.0%), while erlotinib was more frequently used in the second-line setting (83.0%). Progression-free survival (PFS) and overall survival (OS) in patients harbouring common mutations were 11.1 months and 20.1 months respectively (exon 19 deletions: 12.4 and 21.4 months; L858R: 8.3 and 14.5 months), and 3.9 months and 11.1 months respectively for those with rare mutations. CONCLUSION: EGFR TKIs (gefitinib and erlotinib) are used as the preferred first-line treatment while chemotherapy is more frequently administered as a second- and third-line option in routine clinical practice in Spain. In addition, efficacy data obtained in the real-life setting seem to concur with data from EGFR TKI phase III pivotal studies in NSCLC.

Effect of the essential oils from Melaleuca alternifolia, Melaleuca quinquenervia and Backhousia citriodora on the synthesis of ochratoxin A by Aspergillus niger and Aspergillus carbonarius isolated from tropical wine grapes.

The influence of essential oils (EOs) extracted from the leaves of Melaleuca alternifolia, Melaleuca quinquenervia and Backhousia citriodora on ochratoxin A (OTA) synthesis by fungi was studied. The extraction of EOs was performed by hydrodistillation (Clevenger apparatus) over a 2-h period and subsequently analyzed by GC-MS and GC-FID. The toxigenic activity of the essential oils (31.25; 15.62 and 7.81 µg mL-1) was evaluated by inhibiting the production of OTA by Aspergillus niger and Aspergillus carbonarius in Czapek agar medium culture. The quantification of the toxin was performed by HPLC. The production of OTA was dependent on the fungal species, incubation temperature (15 and 25 °C) and the presence of the essential oils. In tests carried out at 15 °C, the oils caused a reduction in OTA synthesis that ranged from 57.60 to 76.93% and from 54.78 to 98.68% for the fungal species A. carbonarius and A. niger, respectively. At 25 °C, reductions ranged from the 38.66 to 75.93% and from 17.94 to 71.79% for the respective fungi. The study concluded that natural products could be potential biocontrol agents against OTA contamination in food.

Estimation of design and construction costs of third level health centers in colombia / Estimativa de custos de construção e desenho de centros de saúde de terceiro nível na colômbia

Resumen En este artículo se presenta el costo promedio por metro cuadrado en Colombia para el diseño y construcción de hospitales de tercer nivel de complejidad mediante la comparación del costo de diseño y construcción por metro cuadrado obtenido en otros países y en proyectos nacionales. Debido al total de la población colombiana y al número de camas disponibles existe un déficit del 42.3%, teniendo 1.5 camas por cada mil habitantes. De acuerdo con lo recomendado por la Organización Mundial de la Salud (OMS) este debe ser de 2.6 camas por cada mil habitantes. Por consiguiente, se requieren más proyectos de diseño y construcción de hospitales en los próximos años.

Abstract This article states the average cost per square meter in Colombia for the design and construction of third level complexity hospitals by comparing the design and construction square meter cost obtained in other countries and national projects. Due to the Colombian population and the number of beds there is a deficit of 42.3%, having 1.5 beds per thousand habitants. As recommended by the World Health Organization (WHO) which is 2.6 beds per thousand inhabitants. Therefore, more hospital design and construction projects are required in years to come.

Resumo Neste artigo obtém-se o custo promédio por metro quadrado na Colômbia para o desenho e construção de hospitais de terceiro nível de complexidade, mediante a comparação do custo de desenho e construção por metro quadrado obtido em outros países e em projetos nacionais. Devido à população Colombiana e ao número de camas há um déficit de 42.3%, tendo 1.5 camas por cada mil habitantes. De acordo com o recomendado pela OMS que é 2.6 camas por cada mil habitantes. Pelo que se requerem mais projetos de desenho e construção de hospitais nos próximos anos.

Modulatory effect of the exudates released by the brown kelp Lessonia spicata on the toxicity of copper in early developmental stages of ecologically related organisms.

Lessonia spicata is a key dominant species along the Pacific coast of South America, providing a habitat for many organisms. However, this role can be affected by abiotic stress, such as metals. To counteract the toxic effect, L. spicata, among other seaweeds, releases exudates that bind metals. In this study, tolerances to copper of organisms related to the kelp forest (spores of Ulva lactuca (Chlorophyceae) and L. spicata (Phaeophyceae) and Zoea I of Taliepus dentatus (Milne-Edwards, Crustacea)) were studied; then, exudates are assessed by their protective effect. Exudates increase the 48-h 50% effective concentration (EC50) of the germination of spores from 8 to 23 µg Cu L-1 for U. lactuca and from 119 to 213 µg Cu L-1 for L. spicata and the survival of the larvae Zoea I 48-h 50% of lethal concentration (LC50) from 144 to 249 µg Cu L-1. Results indicated that exudates had a protective effect. Each species is specifically sensitive to copper. Crab larvae Zoea I were able to support higher doses, and exposure before hatching increased their tolerance.

Abundance and diversity of copper resistance genes cusA and copA in microbial communities in relation to the impact of copper on Chilean marine sediments.

Microorganisms have developed copper-resistance mechanisms in order to survive in contaminated environments. The abundance of the copper-resistance genes cusA and copA, encoding respectively for a Resistance Cell Nodulation protein and for a P-type ATP-ase pump, was assessed in copper and non-copper-impacted Chilean marine sediment cores by the use of molecular tools. We demonstrated that number of copA and cusA genes per bacterial cell was higher in the contaminated sediment, and that copA gene was more abundant than cusA gene in the impacted sediment. The molecular phylogeny of the two copper-resistance genes was studied and reveals an impact of copper on the genetic composition of copA and cusA genes.

Composition dynamics of epilithic intertidal bacterial communities exposed to high copper levels.

Copper has a dual role for organisms, both as micronutrient and toxic element. Copper mining activities have an enormous ecological impact because of the extraction process and the consequent release of copper-containing waste materials to the environment. In northern Chile, mainly in the Chañaral coastal area, this phenomenon is clearly evident. The released waste material has caused a strong modification of the area, and copper enrichment of beaches and rocky shores has provoked a decrease in the richness and diversity of many species of macroorganisms. However, the effects that copper enrichment has on microbial (e.g. bacterial epilithic) communities associated with the rocky shore environment are poorly understood. Using a culture-independent molecular approach, field sampling and laboratory microcosm experiments, we determined the effects of copper enrichment on bacterial communities inhabiting the rocky shore environment. Field samples showed a strong effect of copper on the structure of the natural bacterial epilithic communities, and microcosm experiments demonstrated rapid changes in bacterial community when copper is added, and reversibility of this effect within 48 h after copper is removed.

Uso do protocolo Spikes no ensino de habilidades em transmissão de más notícias / Using the Spikes protocol to teach skills in breaking bad news

O termo "má notícia" designa qualquer informação transmitida ao paciente ou a seus familiares que implique, direta ou indiretamente, alguma alteração negativa na vida destes. Por ser uma tarefa tão estressante, muitos médicos a evitam ou a realizam de maneira inadequada. Esse fato traz inúmeras consequências negativas para o paciente e seus familiares. Embora seja objeto de estudo em diversos cursos de Medicina em nível internacional, o tema ainda é pouco abordado por professores e estudantes no contexto brasileiro. O protocolo Spikes descreve de maneira didática seis passos para comunicar más notícias. Esses passos foram utilizados em aula para alunos do terceiro semestre do curso de Medicina da Universidade Estadual do Ceará. Em seguida, os alunos avaliaram o método por meio de perguntas abertas. De maneira geral, foi considerado um modelo válido, apesar de serem consideradas possíveis limitações, como a necessidade de ser individualizado e adaptado a cada situação.

The term "bad news" refers to any information transmitted to patients or their families that directly or indirectly involves a negative change in their lives. Since breaking bad news is a stressful task, many physicians either avoid it or perform it inadequately. This situation has numerous negative consequences for patients and their families. Although the topic has been the object of study in various medical schools around the world, it has still received little attention by faculty and students in Brazil. The SPIKES protocol provides a didactic six-step approach for breaking bad news. These steps were used in the classroom by third-semester medical students at the State University of Ceará, Brazil. The students then evaluated the method using open-ended questions. The method was generally considered valid, despite possible limitations like the need for individualization and adaptation to each specific situation.

Changes in epiphytic bacterial communities of intertidal seaweeds modulated by host, temporality, and copper enrichment.

This study reports on the factors involved in regulating the composition and structure of bacterial communities epiphytic on intertidal macroalgae, exploring their temporal variability and the role of copper pollution. Culture-independent, molecular approaches were chosen for this purpose and three host species were used as models: the ephemeral Ulva spp. (Chlorophyceae) and Scytosiphon lomentaria (Phaeophyceae) and the long-living Lessonia nigrescens (Phaeophyceae). The algae were collected from two coastal areas in Northern Chile, where the main contrast was the concentration of copper in the seawater column resulting from copper-mine waste disposals. We found a clear and strong effect in the structure of the bacterial communities associated with the algal species serving as host. The structure of the bacterial communities also varied through time. The effect of copper on the structure of the epiphytic bacterial communities was significant in Ulva spp., but not on L. nigrescens. The use of 16S rRNA gene library analysis to compare bacterial communities in Ulva revealed that they were composed of five phyla and six classes, with approximately 35 bacterial species, dominated by members of Bacteroidetes (Cytophaga-Flavobacteria-Bacteroides) and α-Proteobacteria, in both non-polluted and polluted sites. Less common groups, such as the Verrucomicrobiae, were exclusively found in polluted sites. This work shows that the structure of bacterial communities epiphytic on macroalgae is hierarchically determined by algal species > temporal changes > copper levels.

The effect of organic ligands exuded by intertidal seaweeds on copper complexation.

Copper complexation in marine systems is mainly controlled by organic matter, partially produced by micro- and macroalgae that release exudates with the capacity to bind metals. This feature is important as it influences bioavailability, bioaccumulation, toxicity, and transport of copper through biological membranes. The release of Cu-complexing ligands by seaweeds cultured under copper excess was studied in the laboratory. Five macroalgae belonging to different functional groups were used, including the filamentous Chaetomorphafirma (Chlorophyta), the foliose Ulvalactuca (Chlorophyta) and Porphyra columbina (Rhodophyta), the corticated Gelidium lingulatum (Rhodophyta), and the leathery Lessonia nigrescens (Phaeophyceae). The concentration of ligands and their copper-binding strength (logK') of exudates released by each species was determined by anodic stripping voltammetry (ASV). The selected algae released exudates in a wide range of concentration (42-117 nM) after 48h of culture, and addition of 157nM copper increased the production of ligands up to 8 times. A relationship between structural complexity or thallus thickness and the amount of ligands released was not observed. The binding strength (logK') varied among species from 7.6 to 8.9, a response that was not modified by exposure to sub-lethal copper excess. The kelp L. nigrescens showed a fast response to copper excess, releasing ligands that reduced toxicity of the metal in hours. Results suggest that intertidal and shallow subtidal macroalgae might have been overlooked regarding their role as producers of organic ligands and, therefore, as modulators of metal complexing capacity in coastal waters.

Changes in bacterial community structure associated with coastal copper enrichment.

Marine bacterial communities isolated from the water column, sediment, the rock surface, and the green seaweed Ulva compressa were studied in an intertidal ecosystem. The study area included a coastal zone chronically affected by copper mine waste disposals. Bacterial community composition was analyzed by terminal restriction fragment length polymorphism (T-RFLP) of 16S rRNA genes, and multivariate analyses of T-RFLP data sets were used for comparisons. Results showed that diversity and richness indexes were not able to detect differences among compartments. However, comparisons within the same compartment clearly showed that copper enrichment was associated with changes in the composition of the bacterial communities and revealed that the magnitude of the effect depends on the compartment being considered. In this context, communities from sediments appeared as the most affected by copper enrichment. The present study also demonstrated that intertidal bacterial communities were dominated by Gammaproteobacteria, Firmicutes, and Actinobacteria and the changes in these communities were mainly due to changes in their relative abundances.

Mediastinal extravasation of doxorubicin.

A 48-year-old woman with a diagnosis of breast carcinoma was treated with adjuvant chemotherapy through a central venous catheter with subcutaneous reservoir (Port-A-Cath). While doxorubicin was administered, the patient presented thoracic pain and breathing distress due to superior vena cava perforation by the central catheter and subsequent extravasation of the drug into the mediastinum. The patient recovered without sequelae with conservative therapy. Cytostatic extravasation via central catheter is an uncommon complication in clinical practice. In this paper we present the first doxorubicin extravasation through a central catheter in adults and review the only ten cases found in the literature.

Mediastinal extravasation of doxorubicin

A 48-year-old woman with a diagnosis of breast carcinoma was treated with adjuvant chemotherapy through a central venous catheter with subcutaneous reservoir (Port-A-Cath). While doxorubicin was administered, the patient presented thoracic pain and breathing distress due to superior vena cava perforation by the central catheter and subsequent extravasation of the drug into the mediastinum. The patient recovered without sequelae with conservative therapy. Cytostatic extravasation via central catheter is an uncommon complication in clinical practice. In this paper we present the first doxorubicin extravasation through a central catheter in adults and review the only ten cases found in the literature (AU)

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Effects of copper on early developmental stages of Lessonia nigrescens Bory (Phaeophyceae).

Copper effects on the early developmental gametophytic and sporophytic stages of the kelp Lessonia nigrescens were tested in gradients of increasing concentrations of ASV-labile copper. The results demonstrated a high sensitivity to copper of all life-history stages of the alga, where even the lowest tested concentration affected spore release as well as their subsequent settlement. More significant, concentrations higher than 7.87 microg L(-1) totally interrupted the development of the spores after they settle. This effect led to a failure in the formation of male and female gametophytes and, as a consequence, to a complete disruption of the normal life cycle of the kelp. Thus, we suggest that the absence of L. nigrescens from copper-enriched environments results from the high sensitivity of its early life cycle stages, which limits growth and maturation of the gametophytic microscopic phase and, as a consequence, prevents development of the macroscopic sporophytic phase.

Cadmium--copper antagonism in seaweeds inhabiting coastal areas affected by copper mine waste disposals.

Cadmium and copper accumulation by macroalgae was studied in a coastal area exposed to upwelling events and high levels of Cu, the latter resulting from mine disposals. Eight species were studied, and all had very high concentrations of Cd outside of the Cu-contaminated area. Cu in algal tissues was much higher in contaminated than in reference sites. High Cu appeared to suppress Cd bioaccumulation; Cd in algal tissues was much lower in the Cu-contaminated area than in the reference sites. Transplant experiments with Lessonia nigrescens revealed a depuration of Cd in individuals transplanted to areas with high Cu. However, Cd depuration occurs more slowly than Cu uptake. These differences suggest that while Cd and Cu are linked mechanistically, itis nota simple substitution. Overall, the work confirms that macroalgae are useful indicators of metal contamination and may be used as in situ biomonitors for labile forms of metals, like free Cu2+. However, antagonistic relationships between metals must be clearly understood in order to properly interpret their concentrations in macroalgae.