Síndrome de efusión uveal espontáneo

CLINICAL CASE

This was a 73 year-old male patient who developed an apparent uveal effusion syndrome in his right eye one year after cataract surgery. Once possible associated conditions were discarded, a diagnosis of spontaneous uveal effusion syndrome was reached. With appropriate systemic steroid therapy, a favourable response occurred.

DISCUSSION

The diagnosis of uveal effusion may sometimes be difficult to establish. In order to diagnose and manage these patients, a detailed clinical examination along with fluorescein angiography, ultrasonography, ultrasound biomicroscopy (UBM) and magnetic resonance imaging (MRI) tests, must be carried out.

Estimation of nutrient load from urban diffuse sources: experiments with runoff sampling at pilot catchments of Lake Balaton, Hungary

About a quarter of the total nutrient loading of Lake Balaton (Hungary) originates from urban diffuse sources, mostly from direct shoreline watersheds. This load cannot be measured directly. Sampling of urban runoff can help improving load estimations. The dynamic processes characterizing the accumulation and washoff of contaminants suggest that randomly observed concentrations are likely under- or overestimated. The results of two recent pilot programs aimed towards achieving continuous measurement of nutrient load carried by urban runoff are introduced. Stations were implemented in two pilot catchments located on the shore of Lake Balaton. Storm event runoff was sampled automatically and manually. Discharge, precipitation and rainfall intensities were also recorded. Results proved that the more a specific pollutant is associated with solid particles, the more of its load comes from a few but large storm events, nevertheless the cumulative effect of small rainfall events is not negligible, either. Event mean concentrations of solid-related pollutants were found to be dependent on rainfall intensity. The derived empirical relationships for SS, TP and TN event mean concentrations were indeed found to be applicable for reducing the uncertainty of load estimations of these pollutants significantly, as compared to using long-time average (i.e. annual mean) concentration values.

Oceans and human health: Emerging public health risks in the marine environment

There has been an increasing recognition of the inter-relationship between human health and the oceans. Traditionally, the focus of research and concern has been on the impact of human activities on the oceans, particularly through anthropogenic pollution and the exploitation of marine resources. More recently, there has been recognition of the potential direct impact of the oceans on human health, both detrimental and beneficial. Areas identified include: global change, harmful algal blooms (HABs), microbial and chemical contamination of marine waters and seafood, and marine models and natural products from the seas. It is hoped that through the recognition of the inter-dependence of the health of both humans and the oceans, efforts will be made to restore and preserve the oceans.

Long term effects of azithromycin in patients with cystic fibrosis: A double blind, placebo controlled trial

BACKGROUND

Macrolides display immunomodulatory effects that may be beneficial in chronic inflammatory pulmonary diseases. The aim of the study was to document whether long term use of azithromycin may be associated with respiratory benefits in young patients with cystic fibrosis.

METHODS

A multicentre, randomised, double blind, placebo controlled trial was conducted from October 2001 to June 2003. The criteria for enrollment were age older than 6 years and forced expiratory volume in 1 second (FEV1) of 40% or more. The active group received either 250 mg or 500 mg (body weight < or > or =40 kg) of oral azithromycin three times a week for 12 months. The primary end point was change in FEV1.

RESULTS

Eighty two patients of mean (SD) age 11.0 (3.3) years and mean (SD) FEV1 85 (22)% predicted were randomised: 40 in the azithromycin group and 42 in the placebo group. Nineteen patients were infected with Pseudomonas aeruginosa. The relative change in FEV1 at month 12 did not differ significantly between the two groups. The number of pulmonary exacerbations (count ratio 0.50 (95% CI 0.32 to 0.79), p < 0.005), the time elapsed before the first pulmonary exacerbation (hazard ratio 0.37 (95% CI 0.22 to 0.63), p < 0.0001), and the number of additional courses of oral antibiotics were significantly reduced in the azithromycin group regardless of the infectious status (count ratio 0.55 (95% CI 0.36 to 0.85), p < 0.01). No severe adverse events were reported.

CONCLUSION

Long term use of low dose azithromycin in young patients with cystic fibrosis has a beneficial effect on lung disease expression, even before infection with Pseudomonas aeruginosa.

Conservative use of chest-tube insertion in children with pleural effusion

The aim of this work was to evaluate the effect of a more conservative use of chest-tube insertion on the short-term and long-term outcome of pleural infection. Sixty-five patients with pleural infection, aged 1 month to 16 years were each treated according to one of the two protocols: classical management with chest-tube insertion (classical group, n = 33), or conservative use of chest-tube insertion (conservative group, n = 32), with drainage indicated only in the case of voluminous pleural effusion defined by a mediastinal shift and respiratory distress and/or an uncontrolled septic situation. The two groups were comparable with regard to age, baseline C-reactive protein (CRP) value and white blood cell counts, pleural thickness, identified bacteria, and antibiotic treatment. Chest-tube insertion was performed in 17 patients (52%) of the classical group compared to eight patients (25%) of the conservative group (P = 0.03). Duration of temperature above 39 degrees C was shorter in the conservative group (10 +/- 1 vs. 14 +/- 1 days, P = 0.01), as was the normalization of CRP (13 +/- 1 vs. 17 +/- 1 days, P = 0.03). Duration of hospitalization and intravenous (IV) antibiotherapy as well as the delay of chest-radiograph normalization was not significantly different between the two groups. A more conservative use of chest-tube insertion did not change short- and long-term outcome of the pleural infection in children. Drainage could be restricted to the most severely affected patients with pleural empyema causing a mediastinal shift and respiratory distress and/or presenting with an uncontrolled septic situation.

Sniff nasal inspiratory pressure: what is the optimal number of sniffs?

Sniff nasal inspiratory pressure (SNIP) measurement is a volitional noninvasive assessment of inspiratory muscle strength. A maximum of 10 sniffs is generally used. The purpose of the present study was to investigate whether the maximum SNIP improved after the tenth sniff. In total, 20 healthy volunteers and 305 patients with various neuromuscular and lung diseases were encouraged to perform 40 and 20 sniffs, respectively. The best SNIP among the first 10 sniffs was lower than the best SNIP among the next 10 sniffs in the healthy volunteers and patients. The SNIP improvement after the twentieth sniff was marginal. In conclusion, a learning effect persists after the tenth sniff. The current authors suggest using 10 additional sniffs when the best result of the first 10 sniffs is slightly below normal, or when sniff nasal inspiratory pressure is used to monitor a progressive decline in inspiratory muscle strength.

Les gènes modificateurs dans la mucoviscidose

Cystic fibrosis is the most common lethal autosomal recessive disease among the Caucasian population. It is caused by defects in the CFTR gene (Cystic Fibrosis Transmembrane Conductance Regulator). Although over 1600 disease-causing mutations in the CFTR gene have been described, the highly variable disease phenotype in cystic fibrosis cannot be explained on the basis of this gene alone. Both the environment and other non-CFTR genes are likely to be important. The increased understanding of pathophysiological processes in the cystic fibrosis lung has led to several studies on genes in these pathways. One of the major aims of such studies is to produce targets for novel drug developments.

Endoluminal Angioplasty of the Popliteal Artery. Review of 54 Consecutive Patients

AIM

To determine the results of endoluminal angioplasty for occlusive or stenotic lesions of the popliteal artery.

METHODS

Retrospective study of symptomatic patients having popliteal occlusive lesions treated by endoluminal balloon angioplasty. All patients underwent systematic preoperative and postoperative color duplex scan and preoperative angiography. The principal endpoints were primary and primary assisted patency.

RESULTS

Fifty-four percutaneous endoluminal angioplasties of the popliteal artery, including six procedures with stents, were performed in 50 patients. In all cases, the superficial femoral artery was patent and without significant stenosis. Primary patency for the entire cohort was 57.4+/-6.7% at 1 and 2 years. Primary assisted patency was 86.3+/-4.8% at 1 year, and 79.1+/-5.9% at 2 years. The results of angioplasty appeared to be better in patients with intermittent claudication when compared to patients with critical limb ischaemia, (p=0.0006). Angioplasty of single occlusive lesions had a better prognosis than that of multiple occlusive lesions (p=0.01). Results of angioplasty were better at the below-knee and median popliteal artery than at the femoro-popliteal junction or in the above-knee popliteal artery (p=0.03). Tibial run-off and isolated popliteal stenosis versus isolated popliteal thrombosis did not seem to affect primary patency rate.

CONCLUSION

Results of angioplasty of the popliteal artery are acceptable for claudicants, especially those with TASC-A lesions and those with lesions in the distal two thirds of the popliteal artery.

Modelling of geochemical reactions and experimental cation exchange in MX 80 bentonite

Bentonites are widely used for waste repository systems because of their hydrodynamic, surface and chemical-retention properties. MX 80 bentonite (bentonite of Wyoming) contains approximately 85% Na/Ca-montmorillonite and 15% accessory minerals. The dominant presence of Na/Ca-montmorillonite in this clay mineral could cause it to perform exceptionally well as an engineered barrier for a radioactive waste repository because this buffer material is expected to fill up by swelling the void between canisters containing waste and the surrounding ground. However, the Na/Ca-montmorillonite could be transformed to other clay minerals as a function of time under repository conditions. Previous modelling studies based on the hydrolysis reactions have shown that the Na/Ca-montmorillonite-to-Ca-montmorillonite conversion is the most significant chemical transformation. In fact, this chemical process appears to be a simple cation exchange into the engineered barrier. The purpose of the present study was two-fold. Firstly, it was hoped to predict the newly formed products of bentonite-fluid reactions under repository conditions by applying a thermokinetic hydrochemical code (KIRMAT: Kinetic Reactions and Mass Transport). The system modelled herein was considered to consist of a 1-m thick zone of water-saturated engineered barrier. This non-equilibrated system was placed in contact with a geological fluid on one side, which was then allowed to diffuse into the barrier, while the other side was kept in contact with iron-charged water. Reducing initial conditions ( [P(O)2 approximately equals 0] ; Eh=-200 mV) and a constant reaction temperature (100 degrees C) were considered. Secondly, it was hoped to estimate the influence of inter-layer cations (Ca and Na) on the swelling behaviour of the MX 80 bentonite by using an isothermal system of water vapour adsorption and an environmental scanning electron microscope (ESEM) coupled with a digital image analysis (DIA) program. Here, the MX 80 bentonite was previously treated with concentrated solutions (1N) of calcium and sodium chlorides. The results confirmed that the Na/Ca-montmorillonite-to-Ca-montmorillonite conversion was the main chemical transformation in the bentonite barrier under repository conditions. A simplified method (based on volume balance) has shown that the swelling capacity of the engineered barrier would be slightly affected after 1000 years of diffusion-reaction because the volume of neo-formed swelling clays is almost directly proportional to the volume of transformed initial-montmorillonite. Minimal neo-formation of saponites, vermiculites and chlorites was also observed. In addition, an isothermal system of water adsorption and ESEM-DIA methods showed that in the raw-bentonite-to-Ca-bentonite exchange there is a small decrease in the amount of adsorbed water and the swelling potential.

Considerations on the influence of extreme events on the phosphorus transport from river catchments to the sea

In this paper, results from rivers of different sizes in Romania, Hungary and Austria are presented. The paper shows the dynamics of extreme events and their contribution to the total P and suspended solids transported in these rivers. Special attention is paid to the influence of the size of the catchment and the event probability on the relative contribution of a single event to the total loads transported in the river. Further, the development of phosphorus loads along the Danube River at a flood event is shown. From the results it can be concluded that there is no immediate influence of high flow and flood events in upstream parts of the Basin on the transport of phosphorus from the catchment to the receiving Sea. Particle-bound phosphorus is mobilised from the catchment (through erosion) and the river bottom to a high extent at high flow events and transported at peak discharges to downstream, where retention by sedimentation of particles takes place. On the one hand this retention is a transport to flooded areas. In this case it can be considered as more or less long term retention. On the other hand sedimentation takes place in the riverbed, in case the tractive effort of the river is reduced. In this second case the P-pool in the sediments of the sedimentation area will be increased. If anaerobic conditions in the sediment appear, part of the phosphorus will be transformed to soluble ortho-phosphate and will continuously contribute to the phosphorus transport to the receiving sea. Part of the P-retained in the river sediment will be mobilised by resuspension at the next biggest high flow event. Altogether, these alternating processes of suspension, transport, export to flooded areas or sedimentation in the river bed with partly solution and partly resuspension at the next event decrease the share of the phosphorus transport during high flow events on the total loads transported in the more downstream parts of a catchments as compared to the more upstream parts. In the year of occurrence of an extreme flood event the P-transport of this year is dominated by the flood event. As an average over many years the contribution of high flow events to the total P-transport still may be between 7 and 20% in smaller catchments (around 1,000 km2). In a big catchment (e.g. river Danube) much smaller contributions of flood events on the total P-transport can be expected as an average over many years.