Clinical presentation and recurrence of pituitary neuroendocrine tumors: results from a single referral center in Colombia.

INTRODUCTION: Pituitary neuroendocrine tumors (PitNETs) represent 15-18.2% of all intracranial tumors. Their clinical presentation can range from chronic headache, visual defects, hypopituitarism to hormone excess syndromes. PitNETS are commonly classified as functioning neuroendocrine tumors (F-PitNETs) and non-functioning neuroendocrine tumors (NF-PitNETs). At the moment, new classification has emerged based on cell lineages. Almost 50% of all patients with PitNETs require surgical intervention, and about 25% of these have residual and persistent disease that may require additional management. SUBJECTS AND METHODS: A retrospective cohort of medical records of patients with PitNETs, aiming to describe the incidence of recurrence of patients who received surgical treatment over a 12 month follow up period at San Jose Hospital (SJH) in Bogotá, Colombia, over an observation period of 10 years. Furthermore, clinical presentation, biochemical characteristics and immunohistochemistry, postoperative complications are detailed. RESULTS: Eight hundred and eighty-seven patients with pituitary tumors were included in the cohort; 83% (737/887) had a diagnosis of PitNET. Of these, 18.9% (140) received surgical management. The majority 58% (98/140) had nonfunctional-PitNETs (NF-PitNETs), followed by growth-hormone-secreting pituitary adenoma (22.1%; 33/140), adrenocorticotropic- hormone-secreting pituitary adenoma (9.3%; 13/140), and prolactinomas (9.3%; 13/140). A recurrence was found in 45.71% (64/140), subclassified as biochemical in 15.71% (22/140), controlled with medications in 20% (28/140), and remission occurred in 18.57% (26/140). CONCLUSION: Clinical presentation and incidence of recurrence in patients with PitNETs in a referral center in Colombia are similar to other surgical cohorts with low cure rates and high recurrence.

[Features of patients admitted with COVID-19 to a Chilean regional hospital during the first stages of the pandemic]. / COVID-19 en adultos en el Hospital de Puerto Montt en la primera etapa de la pandemia.

BACKGROUND: The COVID-19 pandemic posed a great strain in health services. AIM: To describe the epidemiological and clinical features of patients with SARS-CoV-2 admitted to a regional hospital in southern Chile between April and August 2020. MATERIAL AND METHODS: Clinical records of all hospitalized patients with RT-PCR (+) for SARS-CoV-2 were retrospectively analyzed. RESULTS: During the study period 226 patients aged 55 ± 18 years (55% men) were admitted. The main comorbidities were high blood pressure in 45%, diabetes in 31% and obesity in 21%. The main symptoms were dyspnea in 70%, cough in 69%, fever in 62% and myalgia in 47%. Pneumonia was the main cause of admission in 66%. Images on admission were compatible with pneumonia in 81%, and with a typical COVID-19 pattern in 84%. In 76% there was five-lobe involvement. Eighty-seven cases (39%) were admitted to critical care, with an APACHE score of 10.9 ± 7.1. Invasive mechanical ventilation was used in 16%, 30% required prone position and 13%, a high-flow nasal cannula. The mean stay in critical care was 13.3 days. The mean duration of invasive mechanical ventilation was 14.1 days. Antimicrobials were used in 55% and dexamethasone in 36%. Twenty-two (9.7%) patients aged 71.7 ± 14 died. A Charlson comorbidity index > 3, heart failure and connection to invasive mechanical ventilation were independent risk factors for death. An age > 65 years alone and other comorbidities were not risk factors. CONCLUSIONS: Viral pneumonia is the main cause of hospitalization for COVID-19, usually extensive and bilateral. The greater severity and poor prognosis of these patients are mainly related to comorbidities.

COVID-19 en adultos en el Hospital de Puerto Montt en la primera etapa de la pandemia / Features of patients admitted with COVID-19 to a Chilean regional hospital during the first stages of the pandemic

BACKGROUND: The COVID-19 pandemic posed a great strain in health services. AIM: To describe the epidemiological and clinical features of patients with SARS-CoV-2 admitted to a regional hospital in southern Chile between April and August 2020. MATERIAL AND METHODS: Clinical records of all hospitalized patients with RT-PCR (+) for SARS-CoV-2 were retrospectively analyzed. RESULTS: During the study period 226 patients aged 55 ± 18 years (55% men) were admitted. The main comorbidities were high blood pressure in 45%, diabetes in 31% and obesity in 21%. The main symptoms were dyspnea in 70%, cough in 69%, fever in 62% and myalgia in 47%. Pneumonia was the main cause of admission in 66%. Images on admission were compatible with pneumonia in 81%, and with a typical COVID-19 pattern in 84%. In 76% there was five-lobe involvement. Eighty-seven cases (39%) were admitted to critical care, with an APACHE score of 10.9 ± 7.1. Invasive mechanical ventilation was used in 16%, 30% required prone position and 13%, a high-flow nasal cannula. The mean stay in critical care was 13.3 days. The mean duration of invasive mechanical ventilation was 14.1 days. Antimicrobials were used in 55% and dexamethasone in 36%. Twenty-two (9.7%) patients aged 71.7 ± 14 died. A Charlson comorbidity index > 3, heart failure and connection to invasive mechanical ventilation were independent risk factors for death. An age > 65 years alone and other comorbidities were not risk factors. CONCLUSIONS: Viral pneumonia is the main cause of hospitalization for COVID-19, usually extensive and bilateral. The greater severity and poor prognosis of these patients are mainly related to comorbidities.

Oxidative stress and alterations in the expression of genes related to inflammation, DNA damage, and metal exposure in lung cells exposed to a hydroethanolic coal dust extract.

BACKGROUND: Open cast mining is well known as a concerning source of environmental and public health problems. This work aimed to obtain a hydroethanolic coal dust extract (≤ 38 µm) and to characterize its composition with particular regard to content of organic compounds by GC/MS, as well as describe its toxicity in vitro on Calu-1 after exposure to several concentrations (0-500 µg/mL). MATERIALS AND RESULTS: Cytotoxicity was measured with MTT assay and DCFH-DA probe was employed to estimate the amount of reactive oxygen species (ROS) in Calu-1 cells. RT-PCR was employed to quantify relative expression of genes associated with inflammation, oxidative stress, as well as metals, and lipid metabolism. Seventeen organic compounds were identified in the extract, highlighting undecane, dodecane, pentadecane and benzo[a]anthracene, 6,12-dimethyl-1,2,3,4-tetrahydro-. Cytotoxicity test showed a decrease trend in the cell viability after 24 h hours from the concentration of 62.5 µg/mL. Further, the extract raised intracellular ROS when compared with control. Expression levels of CYP1A1, IL-8, IL-6, MT1X, and NQO1 were up-regulated when cells were exposed to 125 µg/mL of coal dust, whereas PPAR-α was down-regulated, likely involving aryl hydrocarbon receptor regulation. CONCLUSIONS: In short, this study shows that despite hydroethanolic coal dust extract is not cytotoxic to Calu-1 cells, it produces an elevation of intracellular ROS and alters the expression in marker genes of oxidative stress, inflammation, metal transport, xenobiotic and lipid metabolism. These findings suggest that chemicals present in coal dust are biologically active and may interfere key biochemical process in the living organisms.

Spin-orbit coupling prevents spin channel suppression of transition metal atoms on armchair graphene nanoribbons.

We investigate the spin-dependent electronic and transport properties of armchair graphene nanoribbons including spin-orbit coupling due to the presence of nickel and iridium adatoms by using ab initio calculations within the spin-polarized density functional theory and non-equilibrium Green's function formalism. Our results indicate that the intensity of the spin-flip precession is a direct consequence of the relaxed adsorption sites of the adatoms. We point out that d orbitals of Ni and Ir result in strong dependence on the spin-conserved and spin-flip transmission probabilities. In particular, we show that the presence of spin-orbit coupling can lead to an enhancement of the transmission probabilities especially around resonances arising due to weak coupling with specific orbitals.

Portación de Staphylococcus Aureus en manipuladores de alimentos de servicios gastronómicos de Asunción, Paraguay (2017) / Staphylococcus Aureus in food manipulators of gastronomic services of Asunción, Paraguay (2017)

Introducción: El Staphylococcus Aureus constituye un agente etiológico frecuente de intoxicaciones alimentarias y se encuentra asociado a diversos alimentos. Objetivo: Describir la frecuencia de portación de Staphylococcus Aureus en manipuladores de alimentos de restaurantes de Asunción durante el 2017. Metodología: Se realizó un estudio observacional, prospectivo, descriptivo de corte transversal a manipuladores de alimentos de restaurantes de Asunción durante los meses de mayo a junio del 2017. Se realizaron tres hisopados nasales a cada uno de los 30 manipuladores de alimentos para determinar si la portación era intermitente, permanente u ocasional. Al mismo tiempo fueron realizadas encuestas donde se midieron variables demográficas. Resultados: La prevalencia de portación de Staphylococcus Aureus fue del 33,3 % (10), siendo el 40% (4) esporádica e intermitente y el 20% (2) permanente. En cuanto a las características demográficas de los manipuladores,el 56,66% (17) fueron del sexo masculino, eran solteros 43,33% (13) y el 50% (15) contaban con estudios secundarios completos. El promedio de edad de 29 de los manipuladores fue de 39,5 años con un rango comprendido entre 18 y 85 años. El 23,33% (7) utilizaban guantes a la hora de manipular los alimentos. Además, se pudo observar que el 26,66% (8) utilizaba gorros. Llamó la atención que el 30% (9) de los encuestados no presentaban uñas limpias durante la manipulación. Palabras clave: Staphylococcus Aureus; manipuladores; alimentos.

Introduction: Staphylococcus Aureus is a frequent etiologic agent of food poisoning and is associated with various foods. Objective : To describe the frequency of Staphylococcus Aureus in food handlers of restaurants in Asunción during 2017. Methodology: An observational, prospective, descriptive, cross-sectional study was carried out on food handlers in restaurants in Asuncion during the months of May to June 2017. Three nasal swabs were made to each of the 30 food handlers to determine if the carriage was intermittent, permanent or occasional. At thesame time, surveys were carried out where demographic variables were measured. Results: The prevalence of carrying Staphylococcus Aureus was 33.3% (10), being 40% (4) sporadic and intermittent and 20% (2) permanent. Regarding the demographic characteristics of the manipulators, 56.66% (17) were male, were single 43.33% (13) and 50% (15) had complete secondary education. The average age of 29 of the manipulators was 39.5 years with ranger between 18 and 85 years. 23.33% (7) used gloves when handling food. In addition, it was observed that 26.66% (8) used caps. It was noted that 30% (9) of theres pondents did not have clean nails during handling. Keywords: Staphylococcus Aureus; manipulators; food.

Strain and Bond Length Dynamics upon Growth and Transfer of Graphene by NEXAFS Spectroscopy from First-Principles and Experiment.

As the quest toward novel materials proceeds, improved characterization technologies are needed. In particular, the atomic thickness in graphene and other 2D materials renders some conventional technologies obsolete. Characterization technologies at wafer level are needed with enough sensitivity to detect strain in order to inform fabrication. In this work, NEXAFS spectroscopy was combined with simulations to predict lattice parameters of graphene grown on copper and further transferred to a variety of substrates. The strains associated with the predicted lattice parameters are in agreement with experimental findings. The approach presented here holds promise to effectively measure strain in graphene and other 2D systems at wafer levels to inform manufacturing environments.

Severe Hepatopulmonary Syndrome in a Child with Caroli Syndrome.

Hepatopulmonary Syndrome (HPS) is a potential complication of chronic liver disease and is more commonly seen in the adult population. Caroli Syndrome is a rare inherited disorder characterized by intrahepatic ductal dilation and liver fibrosis that leads to portal hypertension. In children with liver disease, HPS should be considered in the differential diagnosis of prolonged, otherwise unexplained, hypoxemia. The presence of HPS can improve patient priority on the liver transplantation wait list, despite their Pediatric End-Stage Liver Disease (PELD) score. We present a 6-year-old girl with Caroli Syndrome and End-Stage Renal Disease who presented with persistent hypoxemia. The goal of this report is to increase awareness of HPS in children.

Clinical, serologic, and immunogenetic characterization (HLA-DRB1) of late-onset lupus erythematosus in a Colombian population.

INTRODUCTION: Late-onset systemic lupus erythematosus (SLE) represents a specific subgroup that is defined as onset after 50 years of age. Late-onset lupus may have a different clinical course and serological findings, which may delay diagnosis and timely treatment. OBJECTIVES: The objective of this paper is to determine the clinical, serologic, and immunogenetic differences among Colombian patients with late-onset SLE versus conventional SLE patients. METHODOLOGY: This was a cross-sectional study in a Colombian population. Patients and their medical records were analyzed from the services of Rheumatology in Bogotá and met the criteria for SLE, according to the American College of Rheumatology (ACR) revised criteria for the classification of SLE.In a reference group of late-onset SLE patients (98 participants, with an onset after 50 years of age) and a group of conventional SLE patients (72 participants, with an onset of age of 49 years or less), multiple clinical variables (age, clinical criteria for lupus, alopecia, weight loss, fever, Raynaud's phenomenon) and multiple serological variables (blood count, blood chemistry profile, autoantibodies) were analyzed. Additionally, the HLA class II (DRB1) of all the patients was genotyped, including an additional group of patients without the autoimmune disease. Statistical analysis was performed using the STATA 10.0 package. RESULTS: In the group of late-onset lupus, there was a higher frequency of pleurisy (p = 0.002), pericarditis (p = 0.026), dry symptoms (p = 0.029), lymphopenia (p = 0.007), and higher titers of rheumatoid factor (p = 0.001) compared with the group of conventional SLE. Late-onset SLE patients had a lower seizure frequency (p = 0.019), weight loss (p = 0.009), alopecia (p < 0.001), and Raynaud's phenomenon (p = 0.013) compared to the conventional SLE group. In late-onset SLE, HLA DR17 (DR3) was found more frequently compared with individuals without autoimmune disease (OR 3.81, 95% CI 1.47 to 10.59) (p = 0.0016). CONCLUSION: In the Colombian SLE population analyzed, there may be a probable association of several clinical and serologic variants, which would allow the differentiation of variables in the presentation of the disease among patients with late-onset SLE vs. conventional SLE.

Potential control of Aedes aegypti (Diptera: Culicidae) with Piper aduncum L. (Piperaceae) extracts demonstrated by chromosomal biomarkers and toxic effects on interphase nuclei.

Dillapiol, a phenylpropanoid isolate from essential oils of leaves of Piper aduncum (Piperaceae), has insecticidal, fungicidal and antimicrobial activities. The insecticidal activity of dillapiol was tested in vivo on the larvae and pupae of Aedes aegypti, the mosquito vector of dengue. Specifically, the effect of dillapiol on the formation of micronuclei and chromosome aberrations was analyzed. Dillapiol treatments comprised two concentrations of 200 and 400 micro dissolved in well water, and a pure well water control used to rear four generations of mosquitoes. Micronuclei occurred in mitotic diploid and tetraploid chromosomes of larvae; nuclear abnormalities also occurred in interphase, metaphase, telophase, and single nucleus cells of pupae. Mortality, oviposition, chromosome breakage, and anaphase bridges were significantly greater in the extract treatments than in controls. The genotoxic effects of dillapiol described here suggest that this natural product may be a useful alternative for the control of A. aegypti.

Management of neuroendocrine tumors: a meeting of experts from Latin America.

A panel of experts from Latin America convened in Brazil, in May of 2007, for consensus recommendations regarding the management of neuroendocrine tumors (NETs) of the gastrointestinal tract and pancreas. The recently introduced World Health Organization classification of NETs represents a step forward, but the former classification of carcinoids into foregut, midgut and hindgut is still likely to be useful in the near future. Macroscopic description of the tumor should be followed by light microscopic examination and immunohistochemical staining, whereas other techniques might not be widely available in Latin America. Surgery remains the mainstay of treatment for patients with potentially curable tumors, and adequate selection is paramount in order to optimize treatment results. Regarding systemic therapy, patients with well-differentiated tumors or islet-cell carcinomas may be categorized as having indolent disease, while patients with poorly differentiated, anaplastic, and small-cell carcinomas, or with atypical carcinoids, may be approached initially as having aggressive disease. Somatostatin analogues play a cytostatic role in indolent tumors, and chemotherapy may play a role against other, more aggressive NETs. Obviously, there is an urgent need for novel therapies that are effective against NETs.

[Long-term results of suture-free cutanous wound closure in head and neck incisions with octylcyanoacrylate topival skin adhesive]. / Ergebnisse des Wundverschlusses mit Octylcyanoacrylat-Gewebekleber im HNO-Bereich.

BACKGROUND: Cyanoacrylate monomers have been developed for use as skin adhesives. So far, little is known about long-term results concerning functional and aesthetic results of wound closure with octylcyanoacrylate in head and neck region. METHODS: In a prospective, non-randomized study we examined in 59 patients who had undergone surgery in the face and the neck in between 04/99 and 05/00 at the ENT-Department, University of Aachen, Germany. The aesthetic and functional outcome of a cutanous wound closure by use of octylcyanoacrylate was evaluated. Patients were seen preoperatively, postoperatively and in a long-term follow-up (average 7.2 months) for wound control, photographs, and evaluation with a standardized questionnary. RESULTS: In 40 cases a complete follow-up was possible. There were 33 patients (82.5 %) satisfied with the aesthetic and the functional results of wound closure. In four patients (10 %) early complications developed but did not have an impact on the cosmetic result. Three patients showed alterations as hypertrophic scar or persisting redness of the scar in the long-term follow-up. CONCLUSION: Octylcyanoacrylate tissue adhesive was found to be an effective method of skin closure in clean head and neck incisions. It is a fast and simple method of wound closure, providing good cosmetic results with a low infection rate.

Coupling between annual and ENSO timescales in the malaria-climate association in Colombia.

We present evidence that the El Niño phenomenon intensifies the annual cycle of malaria cases for Plasmodium vivax and Plasmodium falciparum in endemic areas of Colombia as a consequence of concomitant anomalies in the normal annual cycle of temperature and precipitation. We used simultaneous analyses of both variables at both timescales, as well as correlation and power spectral analyses of detailed spatial (municipal) and temporal (monthly) records. During "normal years," endemic malaria in rural Colombia exhibits a clear-cut "normal" annual cycle, which is tightly associated with prevalent climatic conditions, mainly mean temperature, precipitation, dew point, and river discharges. During historical El Niño events (interannual time scale), the timing of malaria outbreaks does not change from the annual cycle, but the number of cases intensifies. Such anomalies are associated with a consistent pattern of hydrological and climatic anomalies: increase in mean temperature, decrease in precipitation, increase in dew point, and decrease in river discharges, all of which favor malaria transmission. Such coupling explains why the effect appears stronger and more persistent during the second half of El Niño's year (0), and during the first half of the year (+1). We illustrate this finding with data for diverse localities in Buenaventura (on the Pacific coast) and Caucasia (along the Cauca river floodplain), but conclusions have been found valid for multiple localities throughout endemic regions of Colombia. The identified coupling between annual and interannual timescales in the climate-malaria system shed new light toward understanding the exact linkages between environmental, entomological, and epidemiological factors conductive to malaria outbreaks, and also imposes the coupling of those timescales in public health intervention programs.

An integrated malaria control program with community participation on the Pacific Coast of Colombia.

The study focuses on integrated malaria control in 23 communities on the Pacific Coast of Colombia, with several elements of an ecosystem approach to human health, including malaria-related sociopolitical, ecological, and economic factors. The program fostered community participation. The program presented here had 2 components: implementation and research. The first was conducted in 23 communities, 21 of which lacked adequate health services in terms of education, community participation, prompt diagnosis and complete treatment, and vector control. Research focused on specific vector control measures and the current national health services decentralization process. The project: 1) created a malaria prevention culture in the community; 2) avoided deaths from malaria (no fatal cases in the 3-year period, compared to 5-8 deaths a year previously); 3) avoided cases of cerebral malaria (no cases, as compared to 90-110 per year previously); 4) reduced malaria incidence by 45.36%; 5) decreased length of sick leave from 7.52 to 3.7 days; 6) established a permanent network of microscope technicians and 2-way radio communications; 7) integrated work by local, regional, and outside institutions; 8) demonstrated efficacy of insecticide-impregnated bednets to reduce malaria transmission.

[Low-grade malignant peripheral nerve sheath tumor of the neck soft tissues]. / Niedrig-maligner peripherer Nervenscheidentumor der Halsweichteile.

BACKGROUND: Malignant Peripheral Nerve Sheath Tumours (MPNST) either grow sporadically, after radiation or chemotherapy respectively. In many cases they are associated with Neurofibromatosis I. Because of the multiform histologic picture they are often difficult to differentiate from other soft tissue tumours. PATIENT: We present the case of a sporadic MPNST which developed from the vagus nerve of a 39-year-old patient following radiation of the neck 7 years before. After complete excision there has been no recurrence up to now. RESULTS AND CONCLUSIONS: Sporadic MPNST of the head and neck are comparatively rare. With regard to the strong association with Neurofibromatosis I and the difficult differential diagnosis to other soft tissue tumours the emphasis should be put on excluding further manifestations of Neurofibromatosis I and of secondary tumours.

Expression of basic fibroblast growth factor protein and its down-regulation by interferons in head and neck cancer.

BACKGROUND: Angiogenesis is crucial for tumor growth and metastasis. In several tumors, microvascular density has been shown to correlate with metastasis and aggressiveness. Basic fibroblast growth factor (bFGF) has potent angiogenic activity and has been identified in a wide variety of malignancies including head and neck squamous cell carcinomas (HNSCC). Material and Methods Frozen sections of 50 HNSCC were immunostained for von Willebrand factor and bFGF. Microvessels were counted by light microscopy; bFGF expression was studied at the light and electron microscopic level. Laryngeal cancer cell line HlaC79 was incubated with interferon (IFN) alpha and beta. bFGF quantification was performed by ELISA, and antiproliferative effects were determined by BrdU assay. RESULTS: The mean number of blood vessels (77.5 +/- 23.7) is significantly increased in HNSCC compared with controls (17.1 +/- 5.9). bFGF protein expression was detected in all HNSCC but not in control tissue. An correlation between bFGF expression and mean number of microvessels was found (p <.001). However, no correlation between bFGF expression and the main clinicopathologic features was shown. The long-term exposure (144 hr) of HNSCC cells to noncytostatic concentrations of IFN alpha and beta (>10 U/mL) down-regulated the protein production of bFGF. CONCLUSION: bFGF expression and angiogenesis are enhanced in HNSCC. The higher microvessel density in HNSCC with strong bFGF expression supports the importance of bFGF for tumor angiogenesis. IFN alpha and beta treatment leads to a down-regulation of bFGF expression independent of their antiproliferative effects, suggesting that IFN treatment might result in a reduction of angiogenesis in HNSCC.

Predicting high-risk years for malaria in Colombia using parameters of El Niño Southern Oscillation.

The interannual variation in malaria cases in Colombia between 1960 and 1992 shows a close association with a periodic climatic phenomenon known as El Niño Southern Oscillation (ENSO). Compared with other years, malaria cases increased by 17.3% during a Niño year and by 35.1% in the post-Niño year. The annual total number of malaria cases is also strongly correlated (r = 0.62, P < 0.001) with sea surface temperature (SST) anomalies in the eastern equatorial Pacific, a principal parameter of ENSO. The strong relation between malaria and ENSO in Colombia can be used to predict high and low-risk years for malaria with sufficient time to mobilize resources to reduce the impact of epidemics. In view of the current El Niño conditions, we anticipate an increase in malaria cases in Colombia in 1998. Further studies to elucidate the mechanisms which underlie the association are required. As Colombia has a wide range of climatic conditions, regional studies relating climate and vector ecology to malaria incidence may further improve an ENSO-based early warning system. Predicting malaria risk associated with ENSO and related climate variables may also serve as a short-term analogue for predicting longer-term effects posed by global climate change.

Salinity effects on cadmium accumulation in various tissues of the tropical fiddler crab Uca rapax.

Pollution of water and sediments by industrial discharges of heavy metals, mainly cadmium (Cd), threatens the biota of mangrove ecotones around the mouth of the Tuy river, in northern-central Venezuela. Short-term lethal Cd concentrations were determined in adult male Uca rapax collected from a clean site and kept in 75% seawater (SW). The 96-h LC50 obtained, 380 micromol (=43 mg) Cd liter(-1), is remarkably higher than values previously reported for other crustacean, mollusc or fish species. Tissue accumulation of Cd was examined in crabs acclimated to 125, 75 or 25% SW and exposed to sublethal CdCl2 levels ranging from 9.0 to 225 micromol liter(-1) (i.e. 1.0-25 mg Cd liter(-1)). The metal contents of carapace, gills, hepatopancreas, muscle and hemolymph rose pronouncedly at the highest concentration tested and particularly in the crabs treated in dilute (=25%) SW. In the latter, analyses of the relative distribution of whole-body Cd burden showed that about 80% is in the carapace, 2.4% in the gills, 4% in hepatopancreas, 3% in muscle, 9.3 in other viscerae, 1% is bound to the dried solids of hemolymph and ca. 0.2% appears to be in solution in this fluid. Exposure of crabs to Cd in dilute SW enhances the rates of entry or uptake of the metal, possibly mediated by Ca2+ transport mechanisms, and may exceed the detoxifying capacity of organs such as the hepatopancreas. Thus, Cd may be more harmful to crab populations experiencing frequent fluctuations of ambient salinity, such as are usual in mangrove swamps.