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A better understanding of selenium fate in soils at both short and long time scales is mandatory to consolidate risk assessment models relevant for managing both contamination and soil fertilization issues. The purpose of this study was thus to investigate Se retention processes and their kinetics by monitoring time-dependent distribution/speciation changes of both ambient and freshly added Se, in the form of stable enriched selenite-77, over a 2-years field experiment. This study clearly illustrates the complex reactivity of selenium in soil considering three methodologically defined fractions (i.e. soluble, exchangeable, organic). Time-dependent redistribution of Se-77 within solid-phases having different reactivity could be described as a combination of chemical and diffusion controlled processes leading to its stronger retention. Experimental data and their kinetic modeling evidenced that transfer towards less labile bearing phases are controlled by slow processes limiting the overall sorption of Se in soils. These results were used to estimate time needed for (77)Se to reach the distribution of naturally present selenium which may extend up to several decades. Ambient Se speciation accounted for 60% to 100% of unidentified species as function of soil type whereas (77)Se(IV) remained the more abundant species after 2-years field experiment. Modeling Se in the long-term without taking account these slow sorption kinetics would thus result in underestimation of Se retention. When using models based on Kd distribution coefficient, they should be at least reliant on ambient Se which is supposed to be at equilibrium., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Selenium is both essential and toxic for mammals; the range between the two roles is narrow and not only dose-dependent but also related to the chemical species present in foodstuff. Unraveling the metabolism of Se in plants as a function of Se source may thus lead to ways to increase efficiency of fertilization procedures in selenium deficient regions. In this study, stable-isotope tracing was applied for the first time in plants to simultaneously monitor the bio-incorporation of two inorganic Se species commonly used as foodstuff enrichment sources. Occurrence and speciation of Se coming from different Se sources were investigated in root and leaf extracts of ryegrass (Lolium perenne L.), which had been co-exposed to two labeled Se species ((77)SeIV and (82)SeVI). Although the plant absorbed similar amounts of Se when supplied in the form of selenite or selenate, the results evidenced marked differences in speciation and tissues allocation. Selenite was converted into organic forms incorporated mostly into high molecular weight compounds with limited translocation to leaves, whereas selenate was highly mobile being little assimilated into organic forms. Double-spike isotopic tracer methodology makes it possible to compare the metabolism of two species-specific Se sources simultaneously in a single experiment and to analyze Se behavior in not-hyperaccumulator plants, the ICP-MS sensitivity being improved by the use of enriched isotopes.

Objectives: The aim was to study the association between venous disorders and leg symptoms in the population based cross sectional Bonn Vein Study 1 (BVS1)., Methods: A total of 1,350 men and 1,722 women aged 18-79 years were enrolled into BVS1. Chronic venous insufficiency (CVI), varicose veins (VVs), and clinical classes (C-classes/CEAP [Clinical, Etiological, Anatomical, and Pathophysiological]) were determined by clinical and duplex investigation. Leg symptoms (heaviness, tightness, swelling, pain after standing or sitting, pain while walking, muscle cramps, itching, and restless legs) were assessed in a standardized interview. For 2,624 subjects (48.7% male) with complete information on venous disorders, relevant characteristics and information on at least one leg symptom, multivariate logistic regression analysis was performed., Results: More women (929/63.0%) reported at least one leg symptom within the last 4 weeks than men (560/48.7%). Prevalence of reported symptoms increased with age (45.4% of the 18-29 year olds, 73.9% of the 70-79 year olds). Leg symptoms were more frequent in obese and underweight subjects. As confirmed by clinical and duplex examination 22.6% had VV and 15.8% had CVI. VV (OR: 1.4; CI: 1.1-1.7) and CVI (OR: 1.8; CI: 1.3-2.3) were significantly associated with reporting at least one leg symptom. In particular, there was a positive association of VV and CVI with itching, feeling of heaviness, tightness, swelling, and pain after standing or sitting. C2-C6 showed a statistically significant association with feeling of heaviness, tightness, swelling, and itching, while for pain on walking and muscle cramps this was shifted towards C classes C3-C6 and C3-C4, respectively., Conclusions: Venous disorders show significant associations with several leg symptoms. Itching, feeling of heaviness, or tightness seem to be more closely related than other symptoms. The associations between C classes and symptoms seem to be restricted to classes C2 or higher., (Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Aim: Endovenous thermal ablation (ETA) procedures are catheter-directed, ultrasound (US)-guided thermal methods for treatment in varicose veins disease. Radiofrequency, laser or steam energy thermally denatures vein wall collagen, leading first to vein wall inflammation, then fibrosis and finally to occlusion. The aim of this guideline is to give evidence-based recommendations for ETA procedures., Methods: These guidelines were drafted during a consensus meeting of a group of experts in the field of ETA in June 2012 (Hvar, Croatia) under the auspices of the International Union of Phlebology (IUP). These guidelines review the present state of knowledge as reflected in peer-reviewed published medical literature. The recommendations of these guidelines are graded according to the American College of Chest Physicians Task Force recommendations on Grading Strength of Recommendations and Quality of Evidence in Clinical Guidelines., Results: Recommendations on the use of ETA procedures were made based on the quality of evidence for efficacy, safety, tolerability, cosmetic outcome, patient satisfaction/preference and, where appropriate, on the experts' opinion. Health economics were not considered, since differences in national health systems and pricing make it difficult to form general conclusions that are relevant at an international level., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

A better understanding of Se fate in soils is required for different environmental issues, such as radioactive waste management or soil fertilization procedures. In these contexts, the mobility and speciation of Se have to be studied at both short and long terms after Se inputs. Here, we present a new methodology to monitor simultaneously the reactivity of added (isotopic enriched tracers) and ambient Se at trace level in soils by high-performance liquid chromatography inductively coupled plasma mass spectrometry (ICP-MS) following specific extractions. To do so, the collision/reaction cell of the ICP-MS instrument and the interference corrections were optimized to measure reliably the four major Se isotopes. To exemplify the method capabilities, the behaviors of added (77)Se(IV) and ambient Se were followed up in two soils submitted to an ageing process during 3 months. The solid/liquid distribution of added Se reached a steady state after 1 month while its speciation and distribution among soil solid phases were still changing after 3 months. The results clearly demonstrate that slow processes are involved in Se retention and transformation in soils. The usual short-term experiments (<1 month) performed after Se addition are thus not suitable for long-term risk assessment. Interestingly, the behavior of added Se tended to that of ambient Se, suggesting that ambient Se would be useful to infer the fate of Se input over long time scales.

Background: Despite the frequent use of medical compression stockings (MCS), reliable data are lacking on the frequency of MCS use and experience of patients with the treatment., Patients and Methods: The Bonn Vein Study included 3,072 participants from the general population aged 18 to 79 years (1,350 men/1,722 women). Between 2007 and 2008 (Bonn Vein Study 2) 1,978 participants from the Bonn Vein Study 1 were reinvestigated. This paper combines the results of both investigations., Results: 14.6% (7.5% men, 20.3% women) reported having previously undergone treatment with compression stockings. A mean of 71.3% reported an improvement in their venous disease as a result of MCS treatment. During the 6.6 years of follow-up (Bonn Vein Study 2), significantly more prescriptions of MCS were given to patients in higher CEAP clinical stages. 12.2% of the population in C2 was treated with MCS as were 19.1% in C3 and 27.0% in C4-C6. Among participants with chronic venous insufficiency (CVI) (skin changes up to venous ulcers), about 60% were not treated by MCS or bandages in the past years., Conclusions: These results show that MCS is the most common treatment of venous disorders in the German population. At the same time, these figures also demonstrate severely lacking treatment with MCS in CVI., (© The Authors | Journal compilation © Blackwell Verlag GmbH, Berlin.)

Endoluminal catheter-based procedures enable venous reflex in varicose saphenous veins to be eliminated. The catheter tip is positioned in the sapheno femoral or popliteal junction under ultrasound guidance. The energy necessary to ablate the vein is generated as heat by high-frequency current (radiofrequency) by laser light or by steam. Advantages of this procedure include low invasiveness, subcutaneous infusion anesthesia (SIA), low perioperative morbidity and rapid restoration of mobility of patients.

Speciation analysis of selenium in human urine allowed for the first time the identification of a novel selenium metabolite, Se-methylselenoneine. Despite a concentration at low ppb level, its characterization was achieved after sample purification by solid phase extraction (SPE) followed by the parallel coupling of the bidimensional RP/HILIC chromatography with ICP-MS and ESI-LTQ Orbitrap MS detection. To confirm its biological significance with regards to selenoneine, the recently discovered analog of ergothioneine, and to discard the possibility of sample preparation artifacts, a new method was developed to monitor its actual presence, as well as the occurrence of its sulfur and/or non-methylated analogs, in non-preconcentrated urine and blood samples of non-supplemented humans. It consisted in a HILIC ESI-MS(3) method in high resolution mode (resolution 30 000 at m/z 400) with large isolation width windows for precursor ions. These two particular settings allowed respectively to keep observing the specific mass defect of selenium- and sulfur-containing molecules and to maintain the characteristic selenium pattern in product ions created through MS(n) fragmentations. As a result, all four metabolites were detected in blood and three of them in urine. Moreover, different ratios "methylated/non-methylated" were observed between urine and blood samples, which seemed to indicate their active metabolization. The analytical tool developed here will be of a great importance to further study the occurrence and the potential metabolic role in mammalian organelles, cells and fluids of these very particular and promising redox metabolites.

Aim: Although an increase in volume of the legs during prolonged standing is a well-known phenomenon, there is little information on the initial phase in orthostasis. The aim of this study is to measure the increase in volume and its distribution in the lower extremities during orthostatic stress in healthy and varicose patients., Methods: In this prospective study volume changes of the legs in 16 healthy individuals and 24 patients with varicose veins were investigated using an optoelectric volume measurement system (Perometer®) during 10 minutes in a standing position., Results: We could show that during a 10 minute standing experiment, a significant increase in volume of the entire leg, in both the healthy vein group (2.48%) and the varicose group (2.1%) occurred. Significant volume increase appeared in the upper and lower leg respectively. No significant differences could be demonstrated between right and left leg or between healthy and varicose legs., Conclusion: These results in accordance with other published data indicate that changing position from lying or sitting to standing initially leads to a rapid increase in volume of the leg. These changes take place very quickly and with respect to their volume changes, are significant. The volume increase is following a bi-exponential function fitting to a fast filling compartment (venous pooling) and a slow filling compartment reflecting extravasation. Over the course of the day additional edema formation may occur.

Background: Major side effects after endovenous laser ablation (EVLA) are pain and bruising. Low temperature of the tumescence fluid might cause additional venous constriction and a cooling effect around the vein. The aim of this study was to show outcome and side effects after EVLA of incompetent great saphenous veins (GSV) with a 1470 nm Diode laser (Ceralas E, biolitec) using cold or warm tumescence fluid for anaesthesia., Patients and Methods: Between August and November 2007, 85 consecutive patients (85 legs) with an incompetent GSV were treated by EVLA. The patients were randomized in two groups. In 42 patients (Group A) a warm (37 degrees C) and in 43 patients (Group B) a cold (5 degrees C) tumescence fluid (TF) was used for local anaesthesia in the track of GSV. All patients were re-examined after 1, 10 and 30 days clinically and by duplex for complications and occlusion in the treated vein segment. Patient's satisfaction was assessed on a 0 to 4 points scale., Results: In each group one patient was lost to follow-up. There was no significant difference concerning gender, age, C of CEAP, BMI or diameter of the treated vein. In Group A a mean of 462 ml TF and in Group B a mean of 428 ml TF were used. In Group A the mean LEED (average linear endovenous energy density) was 114 J / cm and in Group B 115 J / cm. In both groups occlusion of the treated veins was achieved for all patients. The diameter of the GSV at 3 cm below the sapheno-femoral junction shrunk from 1.0 to 0.7 cm in both groups. The modified CEAP clinical score improved in Group A from 2.9 to 0.7 (mean value) and in Group B from 3.0 to 1.1. The mean pain score on a scale from 0 to 4 during day 2 to day 10 was 1.2 in Group A and 1.0 in Group B. At this time patients in Group A took a mean of 3.4 and in Group B 1.7 analgetic tablets. Ecchymoses were rare in both groups (4 in Group A, 7 in Group B)., Conclusions: In this prospective randomized comparative study the temperature of the tumescence fluid did not influence the occlusion rate when a high LEED was used. In both groups pain and ecchymoses are less frequent in this study with a 1470 nm diode laser than reported in studies with 810-980 nm systems. Cold tumescence fluid reduced pain slightly and reduced the intake of analgetics significantly.

Background: Sclerotherapy involves the injection of a sclerosing agent for the elimination of intracutaneous, subcutaneous, and transfascial varicose veins., Objective: To update guidelines for sclerotherapy of varicose veins., Methods: The guidelines for sclerotherapy of varicose veins of the German Society of Phlebology were updated and modified through a review of the available literature., Results: Published clinical series and controlled clinical trials provide evidence to support the elimination of intracutaneous and subcutaneous varicose veins using sclerotherapy. Allergic skin reactions occur occasionally as allergic dermatitis, contact urticaria, or erythema. Anaphylaxis is rare. Transient migraine headaches present more frequently in patients treated with foam sclerotherapy than liquid sclerotherapy., Conclusion: Sclerotherapy is the method of choice for the treatment of small-caliber varicose veins (reticular varicose veins, spider veins). If performed properly, sclerotherapy is an efficient treatment method with a low incidence of complications.

The aim of the present study was to investigate selenate toxicity in the unicellular green algae Chlamydomonas reinhardtii as a function of sulphate ion concentration and the relationship with intracellular bioaccumulation. The toxicity of selenate was evaluated by measuring the effect of different selenate concentrations on algal growth during a 96h exposure period. A non-linear regression according to the Hill model was used to describe the dose-effect relationship and estimate the effect concentrations (EC) of selenate. EC(50) values of 0.40[0.24-0.52]micromolL(-1) and of 3.10[1.65-4.86]micromolL(-1) of ambient selenate were obtained, at 8 and 80micromolL(-1) of sulphate ions in the medium, respectively. For non-toxic and low-level ambient selenate concentrations, bioaccumulation in presence of 80micromolL(-1) was one tenth that of 8micromolL(-1) of sulphate ions. When expressed as intracellular selenium burden, EC(50) values determined at 8 and 80micromolL(-1) of sulphate ions were not significantly different (126 and 67nmolSe.10(9)cells(-1), respectively). In conclusion, toxicity appeared to be correlated to selenate bioaccumulation which suggests that toxicity must be linked to intracellular selenium accumulation that is directly dependent on ambient sulphate ions that may compete with selenate for transport sites.

The combination of headspace-solid phase microextraction (HS-SPME) and gas chromatography-inductively coupled plasma mass spectrometry (GC-ICPMS) was evaluated for the determination of volatile selenium metabolites in normal urine samples, i.e. without selenium supplementation. HS-SPME operating conditions were optimised and a sampling time of 10 min was found to be suitable for simultaneous extraction of dimethylselenide (DMSe) and dimethyldiselenide (DMDSe). The amount of DMSe and DMDSe extracted onto fibre coating was calculated in clean matrix, i.e. Milli-Q water, on the basis of depletion experiments. When applied to normal urine samples, the developed method allowed the detection of four volatile selenium containing species, among which DMSe and DMDSe could be quantified by standard additions.

Aim: Major side effects after endovenous laser ablation (EVLA) are pain and bruising. The aim of this study was to compare outcome and side effects after EVLA of incompetent great saphenous veins (GSV) with a 1 470 nm diode laser (Ceralas E, biolitec) using a power of 15 or 25 W., Methods: Between 28 November 2007 and 15 January 2008, 40 consecutive patients (40 legs) with an incompetent GSV were treated by EVLA. The patients were randomized in two groups. In Group A (20 patients) was used a 15-W-power laser and in Group B (20 patients) a 25-W-power laser was used. All patients were re-examined after 1, 10 and 30 days clinically and by Duplex for complications and occlusion in the treated vein segment in a standardized way., Results: There was no significant difference concerning gender, age, C of CEAP, body mass index or diameter of the treated vein. In Group A a mean of 465 mL tumescence fluid (TF) was used and in Group B TF was of 433 mL. In Group A the mean linear endovenous energy density (LEED) was 109.7 J/cm and in Group B 132.6 J/cm. The subgroup Bsub included 16 patients of Group B with a comparable mean LEED of 115.8 J/cm. In all groups occlusion of the treated veins was achieved for all patients. The diameter of the GSV reduced at 3 cm below the sapheno-femoral junction from 1.1 to 0.6 cm, 1.0 to 0.6 cm and 0.9 to 0.6 cm respectively in the three groups. The modified CEAP clinical score improved significantly in all groups. In Group A patients have been administered analgesic tablets for a shorter period. There was also a trend to less postinterventional pain and analgesic use in Group A, but it was not significant. Ecchymosis was rare in both groups (8 in Group A, 7 in Group B)., Conclusions: In this prospective randomized comparative study the power of the laser did not influence the occlusion rate when a high LEED with comparable values was used. In both groups pain and ecchymoses were less frequent in this study with a 1 470 nm diode laser than reported in studies with 810-980 nm systems. A lower power level significantly reduced use of analgesic tablets.

Aim: To assess the mid-term results after endovenous laser ablation (EVLA) of saphenous veins by a standardized duplex and clinical protocol., Methods: A non-randomized prospective trial was performed. We included a total of 67 unselected legs of 65 patients with incompetent great or small saphenous veins (GSV and SSV), confirmed by duplex ultrasound. EVLA was carried out with a 980 nm diode laser in pulsed mode and using tumescent local anaesthesia. All patients were given heparin prophylaxis and compression therapy. Patients underwent standard clinical and duplex follow-up examinations with an average of 2.2 years (0.5-3.5 years) after EVLA., Results: Reflux was eliminated in 59 (88.1%) of the 67 treated veins after 2.2 (SD 0.9) years with an average energy density of 48 J/cm vein (19.8-96.1, SD 13.2). 11.9% of the cases demonstrated antegrade flow without reflux. In 8 of 67 treated legs (11.9%) reflux >0.5 s was still present. In these patients the initial vein diameter was significantly (P=0.01) higher than in the successfully treated limbs. Without reflux, the majority of treated veins, 41 of 59 (69.5%), were no longer detectable by ultrasound. In all groups with still visible veins, there was a diameter reduction of about 50%. Clinical classification (CEAP) and pitting edema similarly improved in all groups, and patient satisfaction was very high across the board. Recurrent varicose veins were significantly more frequent in the reflux group. Severe complications such as deep vein thrombosis or pulmonary embolism did not occur in any of the 67 treated cases., Conclusions: EVLA of the GSV and SSV is a minimally invasive, safe and efficient treatment option with a high mid-term success rate. Not only standardized duplex, but also clinical criteria should be used in assessing the results.

Objective: Venous diseases are among the most frequent diseases in the general population of industrialized countries. The aim of this article is to investigate the population-based prevalence of pathologic reflux in superficial and deep leg veins, taking into account factors as gender, age, and clinical classification of venous disease., Methods: In a population-based cross-sectional study, 3072 subjects aged 18 to 79 years (1350 male, 1722 female, response 59%) were enrolled from October 2000 through November 2001. A standardized interview was conducted to document phlebological history and clinical examinations including duplex sonography of selected superficial and deep leg veins. Pathological reflux was defined as being >500 ms. All participants where classified according to the CEAP classification., Results: Using the highest clinical stage per participant, 9.6% where classified C0, 59.0% C1, 14.3% C2, 13.5% C3, 2.9% C4, and 0.7% C5-C6. A pathological reflux (>500 ms) was found in 35.3% (95% confidence interval [CI] 33.6-37.1) of subjects with 21.0% (95% CI 19.5-22.5) showing reflux in at least one superficial vein and 20.0% (95% CI 18.6-21.5) showing reflux in at least one deep vein. We observed significantly higher reflux prevalence for the superficial veins in women while for the deep veins reflux prevalence were significantly higher in men. Prevalence of reflux in the superficial veins markedly increases with age. In the deep venous system, no clear changes in reflux prevalence with age can be observed. For superficial veins, reflux prevalence is markedly higher with higher C-stages. For the deep veins, the proportion of refluxes is relatively constant in stages C0-C3 with a distinct increase of prevalence from stage C4 onward., Conclusion: Our results show a high prevalence of reflux both for the superficial and the deep venous system. Reflux prevalence is associated with gender, age, and the clinical stage as measured by the CEAP classification. Further longitudinal studies are needed to clarify the relevance of pathological reflux in subjects with otherwise healthy veins.

This paper focuses on the analytical performance improvement of the coupled technique HPLC-ICPMS using on-line collision/reaction cell technology for selenium elemental and speciation analyses at the ng (Se) l(-1) level in aquatic environment. Collision/reaction cell operating parameters were optimised, resulting in selected conditions of 5.5 ml min(-1) H(2) and 0.5 ml min(-1) He mixture. The detection limits obtained were around 5 ng (Se) l(-1) for total analysis, and between 7 and 15 ng (Se) l(-1) depending on the species for speciation analysis. The capability of UV irradiation-hydride generation interfacing to increase detector sensitivity was also evaluated for speciation analysis. The detection limits obtained were in the range 2-8 ng (Se) l(-1) depending on the species. Moreover, such interface allowed to prevent bromine introduction to the ICPMS which is particularly convenient for selenium trace analysis in natural waters as (80)Se is preserved free from BrH interferences. The developed method was validated using certified water with low selenium content (TM Rain 95, NWRI, Canada) and applied to the analysis of different waters.

Objectives: The scientific quality of published clinical trials is generally poor in studies where compression devices have been assessed in the management of venous disease. The authors' aim was to establish a set of guidelines which could be used in the design of future clinical trials of compression treatments for venous diseases., Design: Consensus conference leading to a consensus statement., Methods: The authors form a expert consensus group known as the International Compression Club (ICC). This group obtained published medical literature in the field of compression treatment in venous disease by searching medical literature databases. The literature was studied by the group which attended a consensus meeting. A draft document was circulated to ICC members and revised until agreement between contributors was reached., Results: The authors have prepared a set of guidelines which should be given consideration when conducting studies to assess the efficacy of compression in venous disease., Conclusions: The form of compression therapy including the comparators used in the clinical study must be clearly characterised. In future studies the characteristics of the material provided by the manufacturer should be described including in vivo data on pressure and stiffness of the final compression system. The pressure exerted on the distal lower leg should be stated in mmHg and the method of pressure determination must be quoted.

Aim: To assess the safety and efficacy of sclerotherapy of the great saphenous vein (GSV) comparing standardised polidocanol foam to liquid polidocanol in a randomised controlled trial (RCT)., Methods: A multicentre randomised controlled clinical trial was carried out in which saphenous trunks were treated by sclerotherapy. 106 patients with primary varicose veins due to an incompetent GSV were treated with either standardised 3% polidocanol foam or 3% liquid polidocanol. The primary efficacy criterion was elimination of reflux (<0.5 sec) measured 3 cm below the sapheno-femoral junction (SFJ) by duplex ultrasonography 3 months after the last injection., Results: A significantly greater number of patients were successfully treated by foam sclerotherapy resulting in 69% elimination of reflux compared to 27% patients treated with liquid sclerosant. The secondary endpoints of vein occlusion, reflux time, refilling time and patient satisfaction also improved significantly more in the foam group. The mean number of treatment sessions was 1.3 in the foam group compared to 1.6 in the liquid group. Differences between study centres occurred with a mean of 96% reflux elimination in 6 centres versus 39% in 4 other centres. Centres with a high response rate injected a higher mean volume (4.3 vs. 3.6 ml) in the first session in a vein with a smaller diameter (7.5 mm vs. 8.4 mm). No difference in adverse drug reactions was observed between treatment groups., Conclusions: Standardised 3% polidocanol foam is more efficient and equally safe compared to 3% liquid polidocanol for treatment of GSV. In comparison to other studies a relatively small volume was injected into relatively large veins.

Primary chronic venous disorders, which according to the CEAP classification are those not associated with an identifiable mechanism of venous dysfunction, are among the most common in Western populations. Varicose veins without skin changes are present in about 20% of the population while active ulcers may be present in as many as 0.5%. Primary venous disorders are thought to arise from intrinsic structural and biochemical abnormalities of the vein wall. Advanced cases may be associated with skin changes and ulceration arising from extravasation of macromolecules and red blood cells leading to endothelial cell activation, leukocyte diapedesis, and altered tissue remodeling with intense collagen deposition. Laboratory evaluation of patients with primary venous disorders includes venous duplex ultrasonography performed in the upright position, occasionally supplemented with plethysmography and, when deep venous reconstruction is contemplated, ascending and descending venography. Primary venous disease is most often associated with truncal saphenous insufficiency. Although historically treated with stripping of the saphenous vein and interruption and removal of major tributary and perforating veins, a variety of endovenous techniques are now available to ablate the saphenous veins and have generally been demonstrated to be safe and less morbid than traditional procedures. Sclerotherapy also has an important role in the management of telangiectasias; primary, residual, or recurrent varicosities without connection to incompetent venous trunks; and congenital venous malformations. The introduction of ultrasound guided foam sclerotherapy has broadened potential indications to include treatment of the main saphenous trunks, varicose tributaries, and perforating veins. Surgical repair of incompetent deep venous valves has been reported to be an effective procedure in nonrandomized series, but appropriate case selection is critical to successful outcomes.

Speciation analysis of antimony in marine biota is not well documented, and no specific extraction procedure of antimony species from algae and mollusk samples can be found in the literature. This work presents a suitable methodology for the speciation of antimony in marine biota (algae and mollusk samples). The extraction efficiency of total antimony and the stability of Sb(III), Sb(V) and trimethylantimony(V) in different extraction media (water at 25 and 90 degrees C, methanol, EDTA and citric acid) were evaluated by analyzing the algae Macrosystis integrifolia (0.55+/-0.04mugSbg(-1)) and the mollusk Mytilus edulis (0.23+/-0.01mugSbg(-1)). The speciation analysis was performed by anion exchange liquid chromatography (post-column photo-oxidation) and hydride generation atomic fluorescence spectrometry as detection system (HPLC-(UV)-HG-AFS). Results demonstrated that, based on the extraction yield and the stability, EDTA proved to be the best extracting solution for the speciation analysis of antimony in these matrices. The selected procedure was applied to antimony speciation in different algae samples collected from the Chilean coast. Only the inorganic Sb(V) and Sb(III) species were detected in the extracts. In all analyzed algae the sum of total antimony extracted (determined in the extracts after digestion) and the antimony present in the residue was in good agreement with the total antimony concentration determined by HG-AFS. However, in some extracts the sum of antimony species detected was lower than the total extracted, revealing the presence of unknown antimony species, possibly retained on the column or not detected by HPLC-(UV)-HG-AFS. Further work must be carried out to elucidate the identity of these unknown species of antimony.

Tight junctions (TJs) provide a barrier function, inhibiting solute and water flow through the paracellular space. There had been no analysis until now as to how tight junction molecules could be involved in the pathology of patients with chronic venous insufficiency. The aim of the study was to analyse the expression pattern of TJ-molecules occludin (OCLN), claudin-1 (CLDN-1), claudin-3 (CLDN-3) and claudin-5 (CLDN-5) on mRNA and protein level in patients with edema, venous leg ulcers and healthy controls. Biopsy specimens were taken in healthy individuals and in patients before, and four weeks after compression therapy. mRNA-expression was determined by using reverse-transcriptase and polymerase chain reaction (RT-PCR) and the protein-expression was determined by Western blotting from tissue specimens. Quantification performed determining the expression for TJ-molecules displayed diminished expression for CLDN-1 (p<0.01) and CLDN-5 (p<0.01) in patients with chronic venous insufficiency in comparison with healthy controls on mRNA as well as protein level. No statistical differences were detected for OCLN and CLDN-3 between the edema group and healthy controls. There was a significantly elevated expression (p<0.01) on mRNA and protein level between the leg ulcer group and healthy controls for OCLN and CLDN-3. Densitometric evaluation revealed a more significantly elevated expression (p<0.01) for CLDN-1 and CLDN-5 on mRNA and protein level after four weeks of compression therapy in comparison with prior to treatment for the edema as well as the leg ulcer group. Compression therapy tightens the paracellular barrier via elevated expression of specific TJs and prevents thereby the progression of chronic venous insufficiency due to inhibited permeability of fluid into the perivascular tissue.

Radiofrequency ablation (RFA) and endovenous laser treatment (EVLT) are minimal invasive methods to treat saphenous varicose veins. The short- and mid-term results are excellent with an occlusion rate for RFA of almost 90% after 5 years and about 95% for EVLT after 2 years. Severe side effects are rare in both cases. Prospective randomised comparative studies are available for RFA and surgery showing comparable short-term results and superiority of RFA concerning short-term quality of life outcome. For laser treatment no prospective randomised comparative studies are available. Endovenous treatment is only a part of the complex treatment concept of varicose veins. Insufficient tributaries have to be treated in addition. The fact that the insufficient saphenous vein is treated without high ligation seems not to influence the short-term and mid-term recurrence rates. More prospective randomised comparative studies comparing endovenous treatment and surgery or foam sclerotherapy are necessary to decide which method is the best for which patient.

Sclerotherapy is a standard treatment for intradermal varicose veins and branch varicosities. In the treatment of insufficient saphenous veins, crossectomy and stripping used to be the methods of choice. In the last few years good results have also been reported for endovenous methods such as endovenous laser and radio frequency treatment. Sclerotherapy is more effective and even appropriate for larger saphenous veins when the sclerosing liquid is replaced by a foam agent. This cost-effective approach can be done on an outpatient basis without additional anesthesia. Prospective randomized studies are need to confirm the effectiveness.

This paper presents an improvement for the simultaneous separation of Sb(V), Sb(III) and (CH3)3SbCl2 species by high performance liquid chromatography (HPLC) and its detection by hydride generation-atomic fluorescence spectrometry (HG-AFS). The separation was performed on an anion exchange column PRP-X100 using a gradient elution program between EDTA/KHP (potasium hydrogen phtalate) as first mobile phase and phosphate solutions solution as the second one. The chromatographic separation and the HG-AFS parameters were optimized by experimental design. The best results were obtained by using an elution program with 20 mmol l(-1) EDTA + 2 mmol(-01) KHP solution at pH 4.5, during 1.15 min, then change to 50 mmol l(-1) (NH4)2HPO4 solution at pH 8.3, switching back after 4.0 min to the first mobile phase, until 5 min, with a constant flow rate of 1.5 ml min(-1). Retention time of Sb(V), Sb(III) and trimethylantimony species were 1.22, 2.31 and 3.45 min and the detection limits were 0.13; 0.07 and 0.13 microg l(-1), respectively. Studies on the stability of this antimony species in sea water samples on the function of the elapsed time of storage in refrigerator at 4 degrees C was performed employing the optimized method. Results revealed that Sb(III) is easily oxidized within some hours to Sb(V) in sea water stored at 4 degrees C. However, when the sea water was immediately mixed with EDTA no oxidation of Sb(III) was observed up to 1 week of storage. The proposed methodology was then applied to the antimony speciation in sea water samples.

Speciation analysis of four selenium species (selenite, selenate, selenocystine, and selenomethionine) has been performed by on-line coupling of liquid chromatography (LC), UV decomposition, hydride generation (HG), and atomic-fluorescence spectrometry (AFS). Because only selenite (Se(IV)) can generate hydrides, on-line conversion of organic and inorganic selenium species is discussed. Preliminary study showed that the use of only UV light was not sufficient to reduce selenate, because no absorption is observed for this compound at the main wavelength of the low-pressure mercury lamp (253.7 nm). Thus, new conditions based on addition of a reducing reagent (I-) were developed. Mechanisms of action are proposed to explain selenium species conversions. Because of their compatibility with on-line treatment, phosphate buffers were used for chromatographic separation on an anion exchange column (Hamilton PRP-X100). Detection limits (19-60 pg Se) and repeatability of the technique were close to those obtained by conventional quadrupole ICPMS. Applications to real samples such as water and oysters are presented and emphasize the robustness of the system.

Background: Selenium is an essential trace element that also elicits toxic effects at modest intakes. Investigations of selenium metabolites in urine can help our understanding of the transformations taking place in the body that produce these beneficial and detrimental effects. There is, however, considerable discord in the scientific literature regarding the selenium metabolites thought to play important roles in these biotransformation processes., Approach: We critically assessed the published reports on selenium urinary metabolites, from the first report in 1969 to the present, in terms of the rigor of the data on which structures have been proposed., Content: We present and discuss data from approximately 60 publications reporting a total of 16 identified selenium metabolites in urine of humans or rats, a good model for human selenium metabolism. We assessed the analytical methods used and the validity of the ensuing structural assignments., Summary: Many of the studies of selenium metabolites in urine appear to have assigned incorrect structures to the compounds. The long-held view that trimethylselenonium ion is a major human urinary metabolite appears unjustified. On the other hand, recent work describing selenosugars as major urinary metabolites looks sound and provides a firm basis for future studies.

Venous diseases which require emergency care include deep venous thrombosis, superficial thrombophlebitis and variceal bleeding. The clinical diagnosis of deep venous thrombosis is often inaccurate, but can be confirmed in most cases with noninvasive tools such as sonography and d-dimer testing. Standard therapy includes compression of the leg and low molecular weight heparin in a therapeutic dosage. Superficial thrombophlebitis includes a variety of disease processes involving superficial veins, some thrombotic and others inflammatory. The most important is varicophlebitis or varicothrombosis, which involves the deep venous system in up to 20% of cases. Along with immediate surgical procedures when the thrombus reaches the deep venous system in the groin, short term therapy with low molecular weight heparin can be used. Variceal bleeding is a typical complication of severe varicose veins. It can be treated by elevating the leg and compression therapy. In addition sclerotherapy or ligation of the bleeding vein can be performed.

Garlic and onion, are well known for their medical value, especially in against cancer and anticardiovacular diseases. "Alliins" (S-alk(en)yl-L-cysteine sulphoxides) are sources of major active compounds in Allium plants. Se incorporation into garlic significantly increases activities of garlic in cancer prevention and inhibition. Selenomethionine, selenocysteine and Se-methylselenocysteine have been identified in garlic and onion. Previously we identified gamma-glutamyl-Se-methyl-L-selenocysteine, in extracts of garlic cultivated in Se-rich soil [Med. Res. Rev. 16 (1) (1996) 111], suggesting the possible existence of Se-alk(en)yl-L-cysteine selenoxides (Se-"alliins") in garlic. Several comparative experiments were carried out to demonstrate the existence of Se-"alliins" in Se-enriched garlic and onion. We found that there was one similar time-dependent Se signal in HPLC-inductively coupled plasma MS chromatograms of cold-water extracts of freeze-dried garlic powder and fresh garlic. This signal was lost when the extracts of garlic powder and fresh garlic were stored for 1 day at >4 degrees C, but remained in fresh onion extract at the same storage conditions. These phenomena and possible mechanisms are discussed. An additional experiment showed that Allium species cultivated in Se-rich soil might contain two different Se-"alliins".

A coupling between column liquid chromatography (LC) and atomic fluorescence spectrometry was developed for arsenic speciation. After separation, the compounds are oxidised on-line by UV irradiation, volatilised by hydride-generation and carried to the detector by a stream of argon. A combination of anion-exchange and hydrophobic interactions in a single column (Dionex AS7) was found suitable for the simultaneous separation of organic and inorganic species. Twelve compounds (arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, arsenocholine, trimethylarsine oxide, tetramethylarsonium ion and four arsenosugars) were separated using an acetate buffer and a nitric acid solution as mobile phases. Limits of detection are 4-22 pg. The technique was applied to three marine samples. Arsenobetaine was detected as the main species in all samples, with concentrations varying from 59 to 1947 ng(As) g(-1) of fresh mass.

A recently developed method for the determination of arsenic species (arsenite, arsenate, monomethylarsonate, MMAA, and dimethylarsinate, DMAA) has been applied to the study of arsenic speciation in plants. This method uses ion-exchange liquid chromatography coupled on-line to atomic fluorescence spectrometry through continuous hydride generation. Various extraction procedures have been studied in detail using three plant certified reference materials. None of the procedures tested revealed fully satisfying results with all kinds of plant samples; microwave assisted extraction with 0.3 mol dm-3 orthophosphoric acid was found to be the most convenient for dealing with terrestrial plants. Species stability appears good. This method was applied to real world cultivated plant parts. Arsenate appears to predominate in soils, roots and leaves; unidentified species (probably arsenosugars) play an important role (60%) in rice fruits. Carrot was found to be the most contaminated edible plant part, containing 1 mg kg-1 essentially as arsenate species. MMAA was detected in all soils and some plant parts especially shallots at low levels, whereas DMAA was found only in one soil sample and in hot pepper leaves. Arsenite is a minor component of all soils; it is also present in some plant parts at low levels. However, no evident relationships were found between As speciation in the various plant parts and much more detailed studies will be necessary to elucidate As behaviour in plants.

A three-dimensional liquid chromatographic purification protocol based on sequential size-exclusion, anion-exchange and cation-exchange separation mechanisms was developed for the mapping of seleno compounds in aqueous yeast extracts. The method allowed the demonstration of the presence of more than 30 different seleno compounds. Semi-preparative size-exclusion and anion-exchange chromatography were optimized for maximum resolution using electrospray-compatible buffers in order to purify the compounds for mass spectrometric analysis. Molecular masses were attributed to many of the compounds on the basis of the selenium isotopic pattern in the electrospray mass spectra and of the collision-induced fragmentation patterns. Limitations preventing the ultimate identification of the selenium species detected are discussed.