Hypoplasia of the posterior mitral valve leaflet: Don't forget to look beyond the mitral valve

Hypoplasia of the posterior mitral valve leaflet (PMVL) is a very rare finding in adulthood and can coexist with other congenital heart defects. In this image, a transesophageal echocardiography (TOE) carried out on a 59-year-old woman with a 2-month history of dyspnea revealed a hypoplastic PMVL causing severe mitral regurgitation associated with a secundum-type atrial septal defect (ASD) with left-to-right shunting. This case demonstrates how essential 3-dimensional TOE is for a comprehensive assessment of the mitral valve and to improve the diagnostic accuracy of concomitant congenital heart abnormalities.

Recommendations for the evaluation and management of the anticipated and non-anticipated difficult airway of the Societat Catalana d'Anestesiologia, Reanimació i Terapèutica del Dolor, based on the adaptation of clinical practice guidelines and expert consensus

The Airway Division of the Catalan Society of Anaesthesiology, Intensive Care and Pain Management (SCARTD) presents its latest guidelines for the evaluation and management of the difficult airway. This update includes the technical advances and changes observed in clinical practice since publication of the first edition of the guidelines in 2008. The recommendations were defined by a consensus of experts from the 19 participating hospitals, and were adapted from 5 recently published international guidelines following an in-depth analysis and systematic comparison of their recommendations. The final document was sent to the members of SCARTD for evaluation, and was reviewed by 11 independent experts. The recommendations, therefore, are supported by the latest scientific evidence and endorsed by professionals in the field. This edition develops the definition of the difficult airway, including all airway management techniques, and places emphasis on evaluating and classifying the airway into 3 categories according to the anticipated degree of difficulty and additional safety considerations in order to plan the management strategy. Pre-management planning, in terms of preparing patients and resources and optimising communication and interaction between all professionals involved, plays a pivotal role in all the scenarios addressed. The guidelines reflect the increased presence of video laryngoscopes and second-generation devices in our setting, and promotes their routine use in intubation and their prompt use in cases of unanticipated difficult airway. They also address the increased use of ultrasound imaging as an aid to evaluation and decision-making. New scenarios have also been included, such as the risk of bronchoaspiration and difficult extubation Finally, the document outlines the training and continuing professional development programmes required to guarantee effective and safe implementation of the guidelines.

Muon implantation experiments in films: Obtaining depth-resolved information

Implanted positive muons with low energies (in the range 1-30 keV) are extremely useful local probes in the study of thin films and multi-layer structures. The average muon stopping depth, typically in the order of tens of nanometers, is a function of the muon implantation energy and of the density of the material, but the stopping range extends over a broad region, which is also in the order of tens of nanometers. Therefore, an adequate simulation procedure is required in order to extract the depth dependence of the experimental parameters. Here, we present a method to extract depth-resolved information from the implantation energy dependence of the experimental parameters in a low-energy muon spin spectroscopy experiment. The method and corresponding results are exemplified for a semiconductor film, Cu(In,Ga)Se₂, covered with a thin layer of Al₂O₃, but can be applied to any heterostructure studied with low-energy muons. It is shown that if an effect is present in the experimental data, this method is an important tool to identify its location and depth extent.

Can innovations in traditional pork products help thriving EU untapped pig breeds? A non-hypothetical discrete choice experiment with hedonic evaluation

The EU is supporting measures that stimulate enhanced value-added products in order to conserve local and threatened livestock breeds. Several Traditional Pork Products (TPP) and Innovative Traditional Pork Products (ITPP) with health innovations from four untapped pig breeds in Spain (Porc Negre Mallorquí), Croatia (Turopolje), Italy (Cinta Senese) and Slovenia (Krškopolje) were analysed. Consumers' "Non-hypothetical" willingness to pay (WTP) and hedonic evaluation were investigated. An integrated experimental approach using two Non-Hypothetical Discrete Choice Experiment (NH-DCE) was carried out before and after a hedonic evaluation test. Results showed that the health innovative products (ITPP) received similar and even lower WTP than the "control" products (TPP) from the untapped pig breeds. The TPP outperformed products enriched with healthy ingredients or with reduced undesirable compounds. The potential demand for traditional and "unaltered" product from the rustic pig breeds could contribute to their conservation. A market niche exists, where consumers appreciate these high-quality products and where no "add-ons" are required to enhance their uptake.

Electronic structure and migration of interstitial hydrogen in the rutile phase of TiO2

The formation and migration energies of interstitial hydrogen in rutile TiO₂ are obtained from first principles calculations. The computational approach was based on density functional theory with a semilocal generalised-gradient approximation functional, supplemented with an on-site Hubbard term to account for correlation among the Ti 3d electrons. Charge-transition levels are calculated and compared to previous theoretical studies. The donor character of hydrogen is examined in depth, focusing in particular on the tendency to form polaron-like configurations with the unpaired electron trapped at nearby titanium ions. Distinct minimum-energy paths of hydrogen migration and associated energy barriers were determined by the nudged elastic-band method. The present findings show clearly the strong anisotropy in the energy barriers for migration within the open c channels as opposed to migration crossing adjacent channels of the rutile lattice. For the rate-limiting step which leads to macroscopic diffusion along the c axis the corresponding rate and diffusion coefficient were also determined from transition-state theory. The results are discussed in connection to existing measurements of hydrogen diffusion and recent findings from electron paramagnetic resonance, electron-nuclear double resonance and muonium spectroscopies that probed the spatial localization of the electron spin.

Counterpropagating Radiative Shock Experiments on the Orion Laser

We present new experiments to study the formation of radiative shocks and the interaction between two counterpropagating radiative shocks. The experiments are performed at the Orion laser facility, which is used to drive shocks in xenon inside large aspect ratio gas cells. The collision between the two shocks and their respective radiative precursors, combined with the formation of inherently three-dimensional shocks, provides a novel platform particularly suited for the benchmarking of numerical codes. The dynamics of the shocks before and after the collision are investigated using point-projection x-ray backlighting while, simultaneously, the electron density in the radiative precursor was measured via optical laser interferometry. Modeling of the experiments using the 2D radiation hydrodynamic codes nym and petra shows very good agreement with the experimental results.

Influence of atomic kinetics in the simulation of plasma microscopic properties and thermal instabilities for radiative bow shock experiments

Numerical simulations of laboratory astrophysics experiments on plasma flows require plasma microscopic properties that are obtained by means of an atomic kinetic model. This fact implies a careful choice of the most suitable model for the experiment under analysis. Otherwise, the calculations could lead to inaccurate results and inappropriate conclusions. First, a study of the validity of the local thermodynamic equilibrium in the calculation of the average ionization, mean radiative properties, and cooling times of argon plasmas in a range of plasma conditions of interest in laboratory astrophysics experiments on radiative shocks is performed in this work. In the second part, we have made an analysis of the influence of the atomic kinetic model used to calculate plasma microscopic properties of experiments carried out on magpie on radiative bow shocks propagating in argon. The models considered were developed assuming both local and nonlocal thermodynamic equilibrium and, for the latter situation, we have considered in the kinetic model different effects such as external radiation field and plasma mixture. The microscopic properties studied were the average ionization, the charge state distributions, the monochromatic opacities and emissivities, the Planck mean opacity, and the radiative power loss. The microscopic study was made as a postprocess of a radiative-hydrodynamic simulation of the experiment. We have also performed a theoretical analysis of the influence of these atomic kinetic models in the criteria for the onset possibility of thermal instabilities due to radiative cooling in those experiments in which small structures were experimentally observed in the bow shock that could be due to this kind of instability.

Socio-economics, food habits and the prevalence of childhood obesity in Spain

BACKGROUND

In 2012, the prevalence of obesity and overweight statuses among children in Spain was 9% and 26%, respectively. Concerns about childhood obesity have increased over the past few years, as obesity developed during childhood can persist throughout an individual's lifetime (cohort effect). This study aims to develop a better understanding of the factors influencing the prevalence of obesity in Spain.

METHODS

Microdata from the 2012 National Health Survey are used, and the methodological framework is based on the estimation of a sample selection model.

RESULTS

Results suggest that the prevalence of obesity increases among children who live in households of a lower socio-economic status and households in which parents are obese. Lower levels of childhood physical activity are positively related to the probability of being obese. Finally, there exists a positive relationship between children's body mass index and an inappropriate intake of fresh fruits, fish, pasta and rice, legumes, sweets and soft drinks.

CONCLUSIONS

The methodological framework used in this study is flexible enough to be used in traditional longitudinal studies. Children's and households' lifestyles play a pivotal role in the prevalence of obesity. Policies should be oriented toward changing lifestyles, which would require more multidisciplinary research in the future to reduce childhood obesity.

Mapping natural radioactivity of soils in the eastern Canary Islands

The Canary Islands archipielago (Spain) comprises seven main volcanic islands and several islets that form a chain extending for around 500 km across the eastern Atlantic, between latitudes 27°N and 30°N, with its eastern edge only 100 km from the NW African coast. The administrative province of Las Palmas comprises the three eastern Canary Islands (Lanzarote, Fuerteventura and Gran Canaria). An extensive study of terrestrial gamma dose rates in surface soils has been carried out to cover the entire territory of the province (4093 km²). The average outdoor gamma dose rate in air at 1 m above ground is 73 nGyh^-1 at Gran Canaria, 32 nGyh^-1 at Fuerteventura, and 25 nGyh^-1 at Lanzarote. To complete the radiological characterization of this volcanic area, 350 soil samples at 0-5 cm depth were collected to cover all the geologic typologies of the islands. These samples were measured using high resolution gamma spectrometry to determine the activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K. The average values obtained were 25.2 Bq/kg, 28.9 Bq/kg, and 384.4 Bq/kg, respectively. Maps of terrestrial gamma activity, effective dose, and activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K for the region have been developed through the use of geostatistical interpolation techniques. These maps are in accord with the geology of the islands.

Lessons learnt from the radiological measures performed by the Radiological Emergency Network of Extremadura in the International Emergency Exercise CURIEX 2013

In late 2013 (5th-7th of November), the Cáceres Urgent Response International Exercise (CURIEX 2013) took place to test the Nuclear Emergency Plan of Cáceres (PENCA) with the collaboration of both national and international support teams. The theme of the exercise was the simulation of a nuclear accident at the Almaraz Nuclear Power Plant located in Extremadura (Spain) with release of radioactive plume. From the point of view of radioactive contamination, the CURIEX exercise objective was to assess the capability of the different radiological teams to quantify the radioactive impact that would occur in this environment, a goal in which the Radiological Emergency Network of Extremadura (RARE) is directly implicated. The present paper analyses in detail the environmental radiological and dosimetrical results obtained by the Radiological Emergency Network of Extremadura during the CURIEX exercise. The rapid radioactivity measurement techniques on air and soil samples performed by the RARE's mobile lab involves great uncertainties. However, the results show a relative good effectiveness both in dose rate car-borne measurements and gamma soil spectrometry with uncertainties over 40%. It also shows a good correlation between the dose rate values measured by car-borne apparatus and those calculated from gamma spectrometry measurements. The capability of the RARE's facilities are evaluated in both the measurements, showing whether or not there is a radiological problem, and the transmission of that data to the decision centres in the shortest time. Although the results were highly satisfactory, some shortcomings were detected and therefore some improvements are proposed in the paper, in order to achieve a greater capacity in response to an event with the characteristics simulated in the CURIEX exercise.

Consumers' segmentation based on the acceptability of meat from entire male pigs with different boar taint levels in four European countries: France, Italy, Spain and United Kingdom

Two consumer studies were conducted to know the acceptability of pork with different boar taint levels: test 1 performed in Spain (n=126) and United Kingdom (n=146), and test 2 performed in France (n=139) and Italy (n=140). Each test had 3 types of pork: 'Female meat', 'Low boar tainted meat', and a third type was 'Medium boar tainted meat' or 'High boar tainted meat'. Three main clusters were identified on the basis of 'How delicious do you find this meat?': 1-Pork lovers, 2-Boar meat lovers, 3-Reject boar tainted meat. Additionally, in test 2, a fourth cluster was identified: 'Reject low tainted meat'. A group of 16.2-38.2% of consumers rejected meat from boars, and another group of 12.4-21.7% rated the meat with medium or high levels of boar taint better than the meat from females, identifying a niche for meat from medium and high levels of boar taint, and suggesting the need to select carcasses on the basis of boar taint.

A simple methodology for characterization of germanium coaxial detectors by using Monte Carlo simulation and evolutionary algorithms

The determination in a sample of the activity concentration of a specific radionuclide by gamma spectrometry needs to know the full energy peak efficiency (FEPE) for the energy of interest. The difficulties related to the experimental calibration make it advisable to have alternative methods for FEPE determination, such as the simulation of the transport of photons in the crystal by the Monte Carlo method, which requires an accurate knowledge of the characteristics and geometry of the detector. The characterization process is mainly carried out by Canberra Industries Inc. using proprietary techniques and methodologies developed by that company. It is a costly procedure (due to shipping and to the cost of the process itself) and for some research laboratories an alternative in situ procedure can be very useful. The main goal of this paper is to find an alternative to this costly characterization process, by establishing a method for optimizing the parameters of characterizing the detector, through a computational procedure which could be reproduced at a standard research lab. This method consists in the determination of the detector geometric parameters by using Monte Carlo simulation in parallel with an optimization process, based on evolutionary algorithms, starting from a set of reference FEPEs determined experimentally or computationally. The proposed method has proven to be effective and simple to implement. It provides a set of characterization parameters which it has been successfully validated for different source-detector geometries, and also for a wide range of environmental samples and certified materials.

Microscopic properties of xenon plasmas for density and temperature regimes of laboratory astrophysics experiments on radiative shocks

This work is divided into two parts. In the first one, a study of radiative properties (such as monochromatic and the Rosseland and Planck mean opacities, monochromatic emissivities, and radiative power loss) and of the average ionization and charge state distribution of xenon plasmas in a range of plasma conditions of interest in laboratory astrophysics and extreme ultraviolet lithography is performed. We have made a particular emphasis in the analysis of the validity of the assumption of local thermodynamic equilibrium and the influence of the atomic description in the calculation of the radiative properties. Using the results obtained in this study, in the second part of the work we have analyzed a radiative shock that propagated in xenon generated in an experiment carried out at the Prague Asterix Laser System. In particular, we have addressed the effect of plasma self-absorption in the radiative precursor, the influence of the radiation emitted from the shocked shell and the plasma self-emission in the radiative precursor, the cooling time in the cooling layer, and the possibility of thermal instabilities in the postshock region.

[Exercise-induced left bundle branch block with chest pain related to antimalarial prophylaxis with chloroquine]

Left bundle branch block (LBBB) during exercise can be associated with chest pain. Though this association is mostly correlated with an underlying coronary artery disease, painful LBBB has been described in patients with normal coronary arteries. We report a case of exercise-induced LBBB with typical angina pectoris related to antimalarial prophylaxis with chloroquine in a 66-year old woman with normal coronary arteries, which was reversed after treatment discontinuation. The effect of chloroquine on the electrophysiological properties of nodal cardiac tissue is responsible for this rate-dependent LBBB. Precautions for future antimalarial prophylaxis are also discussed.

Natural radioactivity measurements of beach sands in Gran Canaria, Canary Islands (Spain)

Concentrations of natural radionuclides (226)Ra, (232)Th, (40)K and man-made (137)Cs in most important tourist Gran Canaria beaches have been determined using a high-purity Germanium detector to analyse their radiological hazard. Average values of the activity concentrations of (226)Ra, (232)Th and (40)K were 17.6±1.4, 21.3±1.8 and 480±22 Bq kg(-1), respectively. Observed activity concentration values of (137)Cs were practically negligible from a radiological protection point of view. The results of this paper were compared with others published in the bibliography for beaches and coastal sediments of different countries. The mean external air absorbed dose rate was 43.9±2.8 nGyh(-1), which resulted in an outdoor annual effective dose below the world average. Also, the radium equivalent and the external hazard index were calculated. Results from Gran Canaria beaches showed the low levels of radioactivity, indicating no significant radiological risk related to human activities in the area.

Modeling of population kinetics of plasmas that are not in local thermodynamic equilibrium, using a versatile collisional-radiative model based on analytical rates

We discuss the modeling of population kinetics of nonequilibrium steady-state plasmas using a collisional-radiative model and code based on analytical rates (ABAKO). ABAKO can be applied to low-to-high Z ions for a wide range of laboratory plasma conditions: coronal, local thermodynamic equilibrium or nonlocal thermodynamic equilibrium, and optically thin or thick plasmas. ABAKO combines a set of analytical approximations to atomic rates, which yield substantial savings in computer running time, still comparing well with more elaborate codes and experimental data. A simple approximation to calculate the electron capture cross section in terms of the collisional excitation cross section has been adapted to work in a detailed-configuration-accounting approach, thus allowing autoionizing states to be explicitly included in the kinetics in a fast and efficient way. Radiation transport effects in the atomic kinetics due to line trapping in the plasma are taken into account via geometry-dependent escape factors. Since the kinetics problem often involves very large sparse matrices, an iterative method is used to perform the matrix inversion. In order to illustrate the capabilities of the model, we present a number of results which show that the ABAKO compares well with customized models and simulations of ion population distribution. The utility of ABAKO for plasma spectroscopic applications is also outlined.

Analysis of time-resolved argon line spectra from OMEGA direct-drive implosions

We discuss the observation and data analysis of argon K-shell line spectra from argon-doped deuterium-filled OMEGA direct-drive implosion cores based on data recorded with two streaked crystal spectrometers. The targets were 870 microm in diameter, 27 microm wall thickness plastic shells filled with 20 atm of deuterium gas, and a tracer amount of argon for diagnostic purposes. The argon K-shell line spectrum is primarily emitted at the collapse of the implosion and its analysis provides a spectroscopic diagnostic of the core implosion conditions. The observed spectra includes the He alpha, Ly alpha, He beta, He gamma, Ly beta, and Ly gamma line emissions and their associated He- and Li-like satellites thus covering a broad photon energy range from 3100 to 4200 eV with a spectral resolution power of approximately 500. The data analysis relies on detailed atomic and spectral models that take into account nonequilibrium collisional-radiative atomic kinetics, Stark-broadened line shapes, and radiation transport calculations.

[Left ventricular noncompaction: a cardiomyopathy in young individuals. Description of first cases in Africa]

Left ventricular noncompaction (LVNC) is a recently identified and probably rare congenital cardiomyopathy characterized by changes in the structure of the myocardium secondary to incomplete embryogenesis. The purpose of this report is to describe three cases of LVNC involving African patients. To our knowledge these are the first cases described in Africa. All three patients in this series were men from sub-Saharan Africa ranging in age from 23 to 45 years. The first patient in whom cardiomegaly was recognized on a routine chest x-ray was asymptomatic. The second who presented with exertional dyspnea developed left bundle branch block. The third was admitted to the hospital for acute pulmonary edema. In all three cases transthoracic echocardiography suggested diagnosis. The left ventricle was dilated and hypokinetic and the myocardium exhibited a spongy aspect in association with the presence of prominent trabeculations separated by crypts located at the apex and lateral wall. Color Doppler demonstrated that intratrabecular recesses were filled by intraventricular blood flow. Magnetic resonance imaging (MRI) specifically confirmed this morphological feature. Sudden death due to arrhythmia, cardiac insufficiency, and systemic emboli are the main complications of LVNC. The incidence of LVNC, which is certainly underestimated, is highest in young adults but it can be diagnosed at any age. Echocardiography and MRI are effective tools for detection of the morphologic diagnostic criteria. Recent evidence suggests that LVNC is of genetic origin and the data reported here shows that the underlying mutations are present in sub-Saharan populations. Family screening in African populations is still difficult. Therapeutic management is currently based on symptomatic treatment of cardiac insufficiency and can require techniques not readily available in tropical settings.

[Heart failure due to non-infectious causes in developing countries: etiologic approach and therapeutic principles]

Cardiovascular disease is a major worldwide health problem with a growing impact in developing countries. Heart failure is the clinical manifestation of many advanced cardiac disorders. It can have numerous etiologies and the incidence of non-infectious causes is increasing with socio-economic development, thus illustrating the global nature of this epidemiologic transition. Several of the numerous non-infectious causes of heart failure involve cardiac diseases specific to tropical areas including dilated cardiomyopathy, endomyocardial fibrosis, and peripartum cardiomyopathy. Other widespread disorders are becoming more common as a result of the epidemiologic transition. Cardiovascular risk factors are changing particularly with regard to the incidence of coronary artery disease, ischemic cardiomyopathy, and hypertension-related complications. The purpose of this article is to provide an overview of non-infectious causes of heart failure in terms of frequency, onset, and therapeutic requirements. Symptomatic treatment of heart failure is same as in developing countries but is often delayed due to shortcomings in the care system.

Bronchiolitis due to respiratory syncytial virus in hospitalized children: a study of seasonal rhythm

AIM

The objective of this study was to describe the rhythm of respiratory syncytial virus (RSV) bronchiolitis seasonal outbreaks in hospitalized children.

METHODS

Data was collected from 1324 patients, who were admitted to our hospital with bronchiolitis, over an 11-year period, from 1994 to 2004. The epidemic onset was established according to the epidemic index. Virological diagnosis was made with immunofluorescent assay from nasopharyngeal washings. Rhythm study was carried-out by spectral analysis with the fast-Fourier transformed and cosinor method.

RESULTS

Epidemics begin in September (45%) and October (55%); the highest peak was observed in January, the minimum in August and the end in February (73%), March (18%) and April (9%). When the epidemic outbreak begins sooner, the end is sooner as well. Epidemic onset varies but not its length and the onset was less variable than its conclusion. Spectral analysis showed a 12-months cyclic period along the study years and cosinor analysis demonstrated significant circannual rhythm. When data was segregated by long and short hospital stay, no significant differences were found between the rhythms. Comorbid association among bronchiolitis, otitis and gastroenteritis was very common.

CONCLUSION

Bronchiolitis epidemics onset and conclusion varies along time years in hospitalized infants and showed circannual rhythmicity with a 12-months period.

Pharmacoeconomic analysis of adjuvant therapy with exemestane, anastrozole, letrozole or tamoxifen in postmenopausal women with operable and estrogen receptor-positive breast cancer

OBJECTIVE

To compare the efficiency of adjuvant therapy with aromatase inhibitors or with tamoxifen in postmenopausal women with operable breast cancer and positive estrogen receptors.

MATERIAL AND METHODS

A cost-utility analysis was performed based on a Markov model, from the Spanish National Health Care System perspective, comparing the treatment with exemestane (EXE: 25 mg/day) or tamoxifen (TAM: 20 mg/day) after 2-3 years of monotherapy with TAM; anastrozole (ANA, 1 mg/day) or TAM (20 mg/day) without previous TAM therapy; and letrozole (LET: 2.5 mg/day) or placebo after 5 years of monotherapy with TAM. The follow-up of a hypothetical cohort of women starting treatment at 63 years of age was simulated during 10 and 20 years. The probabilities of transition between health states and quality adjusted life years (QALYs) were obtained from the literature, and the unit costs (euro corresponding to 2004) from a Spanish database.

RESULTS

After 10 and 20 years of follow-up, more QALYs per patient would be gained with the EXE scheme (0.230-0.286 and 0.566-0.708, respectively) than with ANA (0.114 and 0.285) and LET (0.176 and 0.474). The cost of gaining one QALY was lower with the EXE scheme (50,801-62,522 euro and 28,849- 35,371 euro, respectively) than with ANA (104,272 euro and 62,477 euro) and LET (91,210 euro and 49,460 euro). The result was stable for the cost per life-year gained (LYG) and in the sensitivity analysis.

CONCLUSIONS

The EXE scheme after TAM is more cost-effective than the ANA and LET schemes.

[Incidence and risk factors for non-traumatic lower extremity amputation in hemodialysis patients]

BACKGROUND AND AIMS

The purpose of this study was to assess the incidence and risk factors for non-traumatic lower extremity amputation (LEA) in patients on haemodialysis (HD).

METHODS

We investigated our HD population attending our clinic between Jan 1988 and Dec 2002, who had had LEA. Uni- and multivariate analyses were used to determine association of LEA with demographic characteristics such as diabetes, hypertension, smoking, myocardial infarction, stroke, dyslipidaemia, haematocrit, urea, creatinine, calcium, phosphorous, parathyroid hormone (PTH) and albumin levels.

RESULTS

Of 516 patients, 20 (3.9%) underwent 32 amputations; 21 major and 11 minor. The incidence was 1. I amputees/100 p-years. There were 11 (10.8%) diabetics and 9 (2.2%) non-diabetics; incidence of 4.2 and 0.6 amputees/100 p-years, respectively. Non-diabetic amputees were older than non-amputees: 68.9 vs 58.2 years (p = 0.013) and had been on HD longer: 71.4 +/- 44 vs 42 +/- 37 months (p = 0.019). There were 60% deaths within the first year of amputation and the causes were 60% cardiovascular. Univariate analysis indicated significant association of LEA with ageing, diabetes, smoking, myocardial infarction, stroke, high cholesterol, and low PTH levels. Multivariate Cox regression identified independent associations of amputation with diabetes, previous myocardial infarction and stroke and/or transient ischaemic attack.

CONCLUSIONS

The incidence of LEA in HD patients is very high and is associated with diabetes and previous cardiovascular events. Advanced age and longer time on HD are factors related to LEA in non-diabetics. With increasing numbers of diabetics and older people on HD, new strategies are needed for peripheral arterial disease management so as to avoid its progression to critical ischaemia.

Identifying optimal agricultural countermeasure strategies for a hypothetical contamination scenario using the strategy model

A spatially implemented model designed to assist the identification of optimal countermeasure strategies for radioactively contaminated regions is described. Collective and individual ingestion doses for people within the affected area are estimated together with collective exported ingestion dose. A range of countermeasures are incorporated within the model, and environmental restrictions have been included as appropriate. The model evaluates the effectiveness of a given combination of countermeasures through a cost function which balances the benefit obtained through the reduction in dose with the cost of implementation. The optimal countermeasure strategy is the combination of individual countermeasures (and when and where they are implemented) which gives the lowest value of the cost function. The model outputs should not be considered as definitive solutions, rather as interactive inputs to the decision making process. As a demonstration the model has been applied to a hypothetical scenario in Cumbria (UK). This scenario considered a published nuclear power plant accident scenario with a total deposition of 1.7x10(14), 1.2x10(13), 2.8x10(10) and 5.3x10(9)Bq for Cs-137, Sr-90, Pu-239/240 and Am-241, respectively. The model predicts that if no remediation measures were implemented the resulting collective dose would be approximately 36 000 person-Sv (predominantly from 137Cs) over a 10-year period post-deposition. The optimal countermeasure strategy is predicted to avert approximately 33 000 person-Sv at a cost of approximately 160 million pounds. The optimal strategy comprises a mixture of ploughing, AFCF (ammonium-ferric hexacyano-ferrate) administration, potassium fertiliser application, clean feeding of livestock and food restrictions. The model recommends specific areas within the contaminated area and time periods where these measures should be implemented.

A critical evaluation of the strategy project

The STRATEGY project (sustainable restoration and long-term management of contaminated rural, urban and industrial ecosystems; www.strategy-ec.org.uk) addressed the need for a holistic decision framework for the selection of optimal remediation strategies for long-term sustainable management of contaminated areas in Western Europe. The project considered both technical and social aspects of implementing restoration strategies for urban and rural environments. The importance of considering socially relevant objectives in addition to the dose reduction was emphasised. A critical evaluation was carried out on 101 selected countermeasures, (including rural waste disposal options), a model was developed to aid optimising countermeasure strategies and a method of carrying out participatory decision-making suggested. The outputs of the project are described and critically evaluated.

[Acute renal failure secondary to hepatic veno-occlusive disease in a bone marrow transplant patient]

Acute renal failure following bone marrow transplantation is a frequent complication with an incidence ranging 15-30% and with high rates of morbidity and mortality. Numerous potential etiologies can be implicated as chemotherapy regimen, use of nephrotoxic antibiotics, sepsis-induced damage, cyclosporine toxicity and other especific pathologies as graft-v-host disease or veno-occlusive disease of the liver. We report the case of a 41-year-old man who underwent autologous peripheral blood stem cell transplantation and developed and acute renal failure secondary to a fatal veno-occlusive disease of the liver. Incidence, potential predisposing factors, outcome and possibilities of treatment are reviewed.

[Platelet antiaggregation and hemorrhagic risk in hemodialysis]

Although the efficacy of antiplatelet therapy in the prevention of cardiovascular disease in chronic renal failure is not clearly defined, the improvement in cardiovascular disease outcomes in the general population has resulted in its use in dialysis patients. The hemorrhagic risk of hemodialysis patients treated with anti-platelet agents has not been clarified. Our aim was to evaluate the risk of bleeding in hemodialysis patients treated with antiplatelet agents. We assessed haemorrhagic complications (HC) in 190 haemodialysis patients from May 1998 to August 2000. HC was defined an event that required hospitalization and/or blood product transfusion. We evaluated the bleeding events in the haemodialysis patients treated with antiplatelet agents and compare them to those not receiving this therapy to establish the relative risk of bleeding. Uni- and multivariate analyses were conducted to establish the relationships between the haemorrhagic event and the following variables: age, gender, time on dialysis, dialysis membrane (synthetic or cellulosic), systemic anticoagulation during haemodialysis, anaemia (haematocrit), PTH, urea, dialysis efficacy (Kt/V), hypertension, diabetes, use of erythropoietin and antisecretory gastric agents.

RESULTS

81 (42.6%) were treated with antiplatelet agents. Of the 190 patients, 28 (14.7%) had 36 haemorrhagic events (10.3 episodes/100 patient-years); 31 digestive-tract haemorrhages, 4 intracranial and 1 pulmonary. Twenty (24.7%) of patients treated with antiplatelet agents had 16.2 episodes/100 patient-years and 8 (7.3%) without this therapy had 6 episodes/100 patient-years (p < 0.01). In the multivariate analysis the antiplatelet therapy remained associated with higher probability of having a haemorrhagic complication (OR 3.8; CI 95%: 1.52-9.76, p = 0.004). Older age (OR 1.03; CI 95%: 1-1.06, p = 0.043), anaemia (OR 0.91; CI 95%; 0.84-0.9, p = 0.027) and hypertension (OR 2.99; CI 95%: 1.05-8.48, p = 0.039) remained associated with the risk of bleeding. 88.2% of patients that had a digestive-tract haemorrhage with antiplatelet therapy were receiving an antisecretory agent (histamine H2-receptor antagonist or a proton-pump inhibitor).

CONCLUSIONS

1) dialysis patients with antiplatelet therapy had a higher haemorrhagic risk. The relative risk of bleeding was more than three times that of the dialysis population without antiplatelet therapy, and 2) older age and hypertension were associated with the haemorrhagic risk. Optimal correction of anaemia was associated with less probability of bleeding.

[Survey of the necessary follow-up examinations after uncomplicated phacoemulsification surgery]

OBJECTIVE

To evaluate which the minimum number of postoperative examinations after uncomplicated phacoemulsification cataract surgery is needed to assure an appropriate follow-up schedule. We evaluated the number of patients that were excluded from the postoperative follow-up schedule and their causes.

METHODS

A prospective study was performed on 120 eyes (106 patients), that were randomised in two groups: one with two follow-up visits (first day and one month) and another with three postoperative visits (first day, one week and one month).

RESULTS

Fifteen eyes (12.5%) were excluded from the postoperative visits regime: 11 cases (18.9%) in the group of two visits and 4 cases (6.45%) in the group of three visits. In 10 cases (8.33%) the patient excluded himself from the schedule. The most frequent causes were: doubts about the outdoor activity that could be done, trauma, or complaints about the topical medications. Only in 6 cases they came to the clinic. No further complications were detected in the group of 2 examinations as compared with the other group.

CONCLUSIONS

According to the number of patients who left the follow-up schedule as well as the number of complications observed, it appears that in most instances 2 postoperative examinations may be appropriate enough.

[Beneficial effect of AN69 membranes on anemia in hemodialyzed patients]

Biocompatible hemodialysis membranes induce a smaller inflammatory response in hemodialysis patients, and remove a larger amount of higher molecular weight retention products, then cellulose membranes. These phenomena could improve uremic anemia in hemodialysis patients. The objective was to evaluate the effects of biocompatible AN69 membranes on anemia in hemodialysis patients. Twenty-five stable patients undergoing hemodialysis with cuprophane membrane for more than 6 months were studied prospectively. These patients were stratified in 2 groups. Group I (GI): 14 patients switched over to a more biocompatible dialyzer (from cuprophan to AN69) and Group II (GII): 11 patients continued treatment with the same cuprophan membrane. The study lasted 5 months. Baseline hematocrit (%), ferritin (ng/mL), transferrin saturation (%), KTV, PCR (g/kg/day) and dose of erythropoietin (EPO) (UI/week) were measured and were revised monthly. Target hematocrit was 33%-35%. A significant increase of hematocrit became obvious after 2 months in GI without changes in dose of EPO and intensity of dialysis, meanwhile GII remains stable.

CONCLUSION

Hemodialysis using AN69 membranes increases hematocrit without modifying intensity of dialysis.

[Rhabdomyolysis and acute renal failure secondary to statins]

Statins are competitive inhibitors of hydroxy-methyl-glutaryl coenzyme A (HMG-CoA) reductase and are the most commonly used drugs to treat hyperlipidaemia. Muscle toxicity is an adverse effect reported with a low incidence and rarely associated with acute renal failure due to rhabdomyolysis. We describe two patients with chronic renal failure treated with pravastatin and simvastatin who suffered rhabdomyolysis and acute renal failure. One patient started pravastatin several days after cessation of bezafibrate and developed acute renal failure without needing dialysis. The other was treated with simvastatin three years ago and suffered rhabdomyolysis when renal function was impaired after indomethacin was prescribed for backache. He needed hemodialysis because of acute cardiac failure and died from a respiratory infection while on mechanical ventilation. Myopathy was reversible in both patients. We recommend starting statins with the lower doses in chronic renal failure and monitoring muscle enzymes when renal function changes or when new drugs with potential interactions are prescribed.

Experimental confirmation of the predicted shallow donor hydrogen state in zinc oxide

We confirm the recent prediction that interstitial protium may act as a shallow donor in zinc oxide, by direct spectroscopic observation of its muonium counterpart. On implantation into ZnO, positive muons--chemically analogous to protons in this context--form paramagnetic centers below about 40 K. The muon-electron contact hyperfine interaction, as well as the temperature and activation energy for ionization, imply a shallow level. Similar results for the cadmium chalcogenides suggest that such shallow donor states are generic to the II-VI compounds. The donor level depths should serve as a guide for the electrical activity of interstitial hydrogen.

Spatial and temporal evolution of the levels of tritium in the Tagus River in its passage through Caceres (Spain) and the Alentejo (Portugal)

This work is the result of a collaboration between Spanish and Portuguese laboratories. The specific objective was to quantify the time evolution during 1994, 1995 and 1996 of the radioecological impact of the liquid releases of 3H from the Almaraz Nuclear Power Plant (ANPP) in the section of the Tagus River corresponding to Cáceres province in Spain and the Alentejo region in Portugal. We found that the temporal evolution of the levels of tritium depends on the management of the water held in the cooling reservoir of the ANPP and the presence of the dams that exist along the river. This management regime has a 12-month period. Also the movement of the mass of tritiated water (HTO) downriver was much faster during 1996 than 1995 or 1994 due to the hydrological differences between those years and consequently to the different amounts of water transferred between the reservoirs of the dams. From the hypothesis that hydrodynamically it is impossible to differentiate tritiated water from non-tritiated water, a model was constructed that satisfactorily reproduces the temporal evolution of the 3H in the zone of the Tagus River in which the exchange of water takes place, with the cooling reservoir of the Almaraz Nuclear Power Plant.

Influence of atrial fibrillation on the morbido-mortality of patients on hemodialysis

BACKGROUND

The consequences of atrial fibrillation (AF) on morbido-mortality of patients on hemodialysis have not been fully explored. The objective of this study was to determine the prevalence of AF in patients on hemodialysis and to evaluate its influence on the development of thromboembolic phenomena (TEP).

METHODS

The incidence of AF in 190 patients in our hemodialysis program was assessed, and the patients were followed up for 1 year. Pertinent demographic and biochemical parameters were entered into univariate and multivariate statistical analyses to evaluate associations with overall mortality and TEP such as cerebrovascular accident, transitory ischemic accident, or peripheral embolism.

RESULTS

In 13.6% of patients, AF was found; 9.4% of these were of the permanent type. In the multivariate analysis, only increased age was associated with a higher probability of having arrhythmia (odds ratio, 1.10; 95% confidence interval, 1.03-1.17; P =.003). During follow-up, 23% of the patients with AF died compared with 6% of those in sinus rhythm (P <.05), although AF did not appear to be an independent predictive factor for death. Thirty-five percent of the patients with AF and 4% with sinus rhythm had TEP (P <.01). In the multivariate analysis, AF was identified as the only independent predictor for TEP (odds ratio, 8; 95% CI, 2.3-27; P =.0008).

CONCLUSIONS

AF is a frequent arrhythmia in patients on hemodialysis, and approximately 1 in 3 hemodialysis patients with AF had thromboembolic complications within 1 year of follow-up. These findings suggest that the consensus contraindication of prophylactic anticoagulation therapy for this group of patients may need to be redefined.

[Nonepithelial malignant degeneration of esophageal duplication]

A communicating duplication of the distal esophagus was diagnosed in an elderly patient. The lesion was removed and the connection with the esophageal lumen closed. A high grade leiomyosarcoma involving all duplication layers and the right pleural surface was demonstrated. This is the first reported instance of a nonepithelial malignant tumor in an alimentary tract duplication.

[An analysis of the level of accuracy of the official diagnosis of temporary work incapacity]

OBJECTIVE

To assess the precision of the Sickness Certificate (SC) issued for Temporary Unfitness for Work (TUW). To measure the percentage of TUW where the diagnoses in the medical records and in the TUW Sickness Certificate do not coincide. To seek objective criteria to determine TUW.

DESIGN

A descriptive, prospective and observational study.

SETTING

Health Centre in an urban area in Vitoria.

PATIENTS AND OTHERS PARTICIPANTS

All the sickness occasioning time off work between May and July, 1991, recorded at the above Health Centre: a sample of 224 TUW.

MEASUREMENTS AND MAIN RESULTS

In 11.6% of the TUW the diagnoses did not coincide. The main reasons for the lack of correspondence were: initial ignorance of the diagnosis (34.6%); confidentiality before a third party (25.9%); pretense (14.8%). There was a notable difference between the psychological diagnoses (12) and those found in the official certificate 3 for TUW (p = 0.032). The most common diagnostic group was the locomotive one (29%).

CONCLUSIONS

There is considerable inexactness in the diagnoses on the official TUW certificate. A lot of time off for psychological reasons is covered up by organic complaints. The locomotive group of complaints is the most commonly found one. We propose that the CIAP classification should be adopted to standardise diagnoses in this area.