Comparison in waterborne Cu, Ni and Pb bioaccumulation kinetics between different gammarid species and populations: Natural variability and influence of metal exposure history.

Kinetic parameters (uptake from solution and elimination rate constants) of Cu, Ni and Pb bioaccumulation were determined from two Gammarus pulex and three Gammarus fossrum wild populations collected from reference sites throughout France in order to assess the inter-species and the natural inter-population variability of metal bioaccumulation kinetics in that sentinel organism. For that, each population was independently exposed for seven days to either 2.5µgL-1 Cu (39.3nM), 40µgL-1 Ni (681nM) or 10µgL-1 Pb (48.3nM) in laboratory controlled conditions, and then placed in unexposed microcosms for a 7-day depuration period. In the same way, the possible influence of metal exposure history on subsequent metal bioaccumulation kinetics was addressed by collecting wild gammarids from three populations inhabiting stations contaminated either by Cd, Pb or both Pb and Ni (named pre-exposed thereafter). In these pre-exposed organisms, assessment of any changes in metal bioaccumulation kinetics was achieved by comparison with the natural variability of kinetic parameters defined from reference populations. Results showed that in all studied populations (reference and pre-exposed) no significant Cu bioaccumulation was observed at the exposure concentration of 2.5µgL-1. Concerning the reference populations, no significant differences in Ni and Pb bioaccumulation kinetics between the two species (G. pulex and G. fossarum) was observed allowing us to consider all the five reference populations to determine the inter-population natural variability, which was found to be relatively low (kinetic parameters determined for each population remained within a factor of 2 of the minimum and maximum values). Organisms from the population exhibiting a Pb exposure history presented reduced Ni uptake and elimination rate constants, whereas no influence on Ni kinetic parameters was observed in organisms from the population exhibiting an exposure history to both Ni and Pb. Furthermore Pb bioaccumulation kinetics were unaffected whatever the condition of pre-exposure in natural environment. Finally, these results highlight the complexity of confounding factors, such as metal exposure history, that influence metal bioaccumulation processes and showed that pre-exposure to one metal can cause changes in the bioaccumulation kinetics of other metals. These results also address the question of the underlying mechanisms developed by organisms to cope with metal contamination.

Ecotoxicoproteomic assessment of the functional alterations caused by chronic metallic exposures in gammarids.

Very few ecotoxicological studies have been performed on long-term exposure under controlled conditions, hence limiting the assessment of the impact of chronic and diffuse chemical pressures on the health of aquatic organisms. In this study, an ecotoxicoproteomic approach was used to assess the integrated response and possible acclimation mechanisms in Gammarus fossarum following chronic exposures to Cd, Cu or Pb, at environmentally realistic concentrations (i.e. 0.25, 1.5 and 5 µg/L respectively). After 10-week exposure, changes in protein expression were investigated in caeca of control and exposed males. Gel-free proteomic analyses allowed for the identification of 35 proteins involved in various biological functions, for which 23 were significantly deregulated by metal exposures. The protein deregulation profiles were specific to each metal, providing evidence for metal-specific action sites and responses of gammarids. Among the tested metals, Cu was the most toxic in terms of mortality, probably linked with persistent oxidative stress. Moulting and osmoregulation were the major biological functions affected by Cu in the long-term. In Pb-exposed gammarids, significant deregulations of proteins involved in immune response and cytoskeleton were observed. Reproduction appears to be strongly affected in gammarids chronically exposed to Cd or Pb. Besides, modified expressions of several proteins involved in energy transfer and metabolism highlighted important energetic reshuffling to cope with chronic metal exposures. These results support the fact that metallic pressures induce a functional and energetic cost for individuals of G. fossarum with potential repercussions on population dynamics. Furthermore, this ecotoxicoproteomic study offers promising lines of enquiry in the development of new biomarkers that could make evidence of long-term impacts of metals on the health of organisms.

Environmental relevance of laboratory-derived kinetic models to predict trace metal bioaccumulation in gammarids: Field experimentation at a large spatial scale (France).

Kinetic models have become established tools for describing trace metal bioaccumulation in aquatic organisms and offer a promising approach for linking water contamination to trace metal bioaccumulation in biota. Nevertheless, models are based on laboratory-derived kinetic parameters, and the question of their relevance to predict trace metal bioaccumulation in the field is poorly addressed. In the present study, we propose to assess the capacity of kinetic models to predict trace metal bioaccumulation in gammarids in the field at a wide spatial scale. The field validation consisted of measuring dissolved Cd, Cu, Ni and Pb concentrations in the water column at 141 sites in France, running the models with laboratory-derived kinetic parameters, and comparing model predictions and measurements of trace metal concentrations in gammarids caged for 7 days to the same sites. We observed that gammarids poorly accumulated Cu showing the limited relevance of that species to monitor Cu contamination. Therefore, Cu was not considered for model predictions. In contrast, gammarids significantly accumulated Pb, Cd, and Ni over a wide range of exposure concentrations. These results highlight the relevance of using gammarids for active biomonitoring to detect spatial trends of bioavailable Pb, Cd, and Ni contamination in freshwaters. The best agreements between model predictions and field measurements were observed for Cd with 71% of good estimations (i.e. field measurements were predicted within a factor of two), which highlighted the potential for kinetic models to link Cd contamination to bioaccumulation in the field. The poorest agreements were observed for Ni and Pb (39% and 48% of good estimations, respectively). However, models developed for Ni, Pb, and to a lesser extent for Cd, globally underestimated bioaccumulation in caged gammarids. These results showed that the link between trace metal concentration in water and in biota remains complex, and underlined the limits of these models, in their present form, to assess trace metal bioavailability in the field. We suggest that to improve model predictions, kinetic models need to be complemented, particularly by further assessing the influence of abiotic factors on trace metal uptake, and the relative contribution of the trophic route in the contamination of gammarids.

Metal measurement in aquatic environments by passive sampling methods: Lessons learning from an in situ intercomparison exercise.

Passive sampling devices (PS) are widely used for pollutant monitoring in water, but estimation of measurement uncertainties by PS has seldom been undertaken. The aim of this work was to identify key parameters governing PS measurements of metals and their dispersion. We report the results of an in situ intercomparison exercise on diffusive gradient in thin films (DGT) in surface waters. Interlaboratory uncertainties of time-weighted average (TWA) concentrations were satisfactory (from 28% to 112%) given the number of participating laboratories (10) and ultra-trace metal concentrations involved. Data dispersion of TWA concentrations was mainly explained by uncertainties generated during DGT handling and analytical procedure steps. We highlight that DGT handling is critical for metals such as Cd, Cr and Zn, implying that DGT assembly/dismantling should be performed in very clean conditions. Using a unique dataset, we demonstrated that DGT markedly lowered the LOQ in comparison to spot sampling and stressed the need for accurate data calculation.

Influence of effluent organic matter on copper speciation and bioavailability in rivers under strong urban pressure.

This study focuses on spatiotemporal variations in the type of dissolved organic matter (DOM) and copper binding ability both upstream and downstream of Paris. It also compares the relative influence of both natural DOM upstream of Paris and effluent dissolved organic matter (EfDOM) output from a wastewater treatment plant (WWTP) on trace metal speciation and bioavailability in aquatic systems. In addition to the typical high- and low-affinity binding sites, a third family of very high-affinity binding sites has been highlighted for EfDOM. In receiving waters downstream of Paris during low-flow periods, the percentage of high- and very high-affinity sites originating from EfDOM reaches nearly 60 %. According to the speciation computation, the free copper concentration upstream of Paris exceeds the downstream Paris concentration by a factor of 2 to 4. As regards copper bioavailability, the highest EC50tot values were observed for EfDOM and downstream DOM, with a very low aromaticity and low UV absorbance. This finding suggests that specific ultraviolet absorbance (SUVA) is unlikely to be useful in assessing metal speciation and toxicity in aquatic systems subject to strong urban pressures. These results also highlight that the copper speciation computation for surface water exposed to considerable human pressures should include not only the humic and/or fulvic part of dissolved organic carbon but more hydrophilic fractions as well, originating for example from EfDOM.

A biodynamic model predicting waterborne lead bioaccumulation in Gammarus pulex: Influence of water chemistry and in situ validation.

Metals bioaccumulated in aquatic organisms are considered to be a good indicator of bioavailable metal contamination levels in freshwaters. However, bioaccumulation depends on the metal, the species, and the water chemistry that influences metal bioavailability. In the laboratory, a kinetic model was used to describe waterborne Pb bioaccumulated in Gammarus pulex. Uptake and elimination rate constants were successfully determined and the effect of Ca(2+) on Pb uptake was integrated into the model. Thereafter, accumulated Pb concentrations in organisms were predicted with the model and compared with those measured in native populations from the Seine watershed (France). The predictions had a good agreement with the bioaccumulation levels observed in native gammarids and particularly when the effect of calcium was considered. To conclude, kinetic parameters experimentally derived for Pb in G. pulex are applicable in environmental conditions. Moreover, the consideration of the water's chemistry is crucial for a reliable interpretation of bioaccumulation.

One-year monitoring of core biomarker and digestive enzyme responses in transplanted zebra mussels (Dreissena polymorpha).

A 12-month active biomonitoring study was performed in 2008-2009 on the Vesle river basin (Champagne-Ardenne, France) using the freshwater mussel Dreissena polymorpha as a sentinel species; allochthonous mussels originating from a reference site (Commercy) were exposed at four sites (Bouy, Sept-Saulx, Fismes, Ardre) within the Vesle river basin. Selected core biomarkers (acetylcholinesterase (AChE) activity, glutathione-S transferase (GST) activity, metallothionein concentration), along with digestive enzyme activities (amylase, endocellulase) and energy reserve concentrations (glycogen, lipids), were monitored throughout the study in exposed mussels. At the Fismes and Ardre sites (downstream basin), metallic and organic contamination levels were low but still high enough to elicit AChE and GST activity induction in exposed mussels (chemical stress); besides, chemical pollutants had no apparent deleterious effects on mussel condition. At the Bouy and Sept-Saulx sites (upstream basin), mussels obviously suffered from adverse food conditions which seriously impaired individual physiological state and survival (nutritional stress); food scarcity had however no apparent effects on core biomarker responses. Digestive enzyme activities responded to both chemical and nutritional stresses, the increase in energy outputs (general adaptation syndrome-downstream sites) or the decrease in energy inputs (food scarcity-upstream sites) leading to mid- or long-term induction of digestive carbohydrase activities in exposed mussels (energy optimizing strategy). Complex regulation patterns of these activities require nevertheless the use of a multi-marker approach to allow data interpretation. Besides, their sensitivity to natural confounding environmental factors remains to be precised.

Labile, dissolved and particulate PAHs and trace metals in wastewater: passive sampling, occurrence, partitioning in treatment plants.

The occurrence and the partitioning of polycyclic aromatic hydrocarbons (PAHs) and seven metals (Al, Cd, Cr, Cu, Ni, Pb and Zn) were investigated in activated sludge wastewater treatment plants by means of passive and active sampling. Concentrations total dissolved and particulate contaminants were determined in wastewater at several points across the treatment system by means of grab sampling. Truly dissolved PAHs were sampled by means of semipermeable membrane devices. Labile (inorganic and weakly complexed) dissolved metals were also sampled using the diffusive gradient in thin film technique. This study confirms the robustness and the validity of these two passive sampling techniques in wastewater. All contaminant concentrations decreased in wastewater along the treatment, although dissolved and labile concentrations sometimes increased for substances with less affinity with organic matter. Solid-liquid and dissolved organic matter/water partitioning constants were estimated. The high variability of both partitioning constants for a simple substance and the poor relation between K(D) and K(OW) shows that the binding capacities of particles and organic matter are not uniform within the treatment and that other process than equilibrium sorption affect contaminant repartition and fate in wastewater.

Reliability of pelvic floor muscle strength measurement in elderly incontinent women.

Pelvic floor muscles (PFM) play an important role in maintaining urinary continence with increasing age. Therefore, their contractile properties need to be evaluated. The aim of the study was to examine the reliability and correlation of simple techniques to measure PFM strength in elderly women with urinary incontinence. An interview was used to evaluate the ability to stop the urinary stream during micturition and to calculate the incontinence index. A pad test was applied to objectively evaluate the severity of the disease. Functional testing included a digital examination to measure the force and duration of one contraction, a perineometer measurement (Peritron) to assess maximal contraction force and contraction force of 5 s, and a cone-retention test (Femcon) while walking for 1 min and during Valsalva's manoeuvre. This procedure was performed on three separate occasions within one week. The 37 participating women with a mean age of 62+/-8 (mean+/-SD) years had a severity index of 4.4+/-2.6 and a urine loss of 9.5+/-13.6 mg during the pad test. Sixteen women were able to completely stop the urinary stream during micturition. The digital examination showed no intratester variability. The perineometer measurement showed that the absolute difference in maximal contraction force and mean contraction force within 5 s was less than 5.3 mm Hg and 4.5 mm Hg, respectively, with a probability of 0.95. While walking and during Valsalva's manoeuvre, 19 and 20 women, respectively, held the same cone in place on all three occasions. The maximal contraction force and mean force during the 5-s contraction correlated well with the ability to stop the urinary stream and the digital examination but only weakly with the cone-retention tests. The reliability of PFM strength measurement is highest in the digital examination, followed by perineometer measurements, and then by vaginal cone tests. As PFM function is easy to assess, it should be routinely done in the assessment of urinary incontinence in elderly women.

A neuromuscular test battery for osteoporotic women: a pilot study.

OBJECTIVE: To examine the efficacy of a short neuromuscular test battery in elderly women suffering from osteoporosis in accordance with the World Health Organization criteria, with and without a history of fractures. Reduced bone mass and a high likelihood of falling increase the risk of osteoporotic fractures. There is a need for neuromuscular tests to identify individuals at risk for falls and fractures. DESIGN: The women were assessed twice. Forty-two women, with a mean age of 70.0 +/- 5.1 (SD) yr, completed the first assessment. The number of postmenopausal fractures and the women's history with regard to agility and falls were assessed. The women performed neuromuscular tests (one-leg stance, tandem walk, and body sway); bone mineral density of the spine and femoral neck were measured. For the follow-up assessment, 13.2 +/- 1.3 mo later, 39 women were studied. The same outcome measurements were obtained at both evaluations. RESULTS: During the observation period, five women fell once and one woman fell twice; there were only two vertebral fractures and no nonvertebral fracture. Neuromuscular performance did not change during this observation period. The median changes in bone mineral density between the two assessments were clinically not relevant. A comparison between patients suffering from established osteoporosis and osteoporotic patients without a history of postmenopausal fractures showed that both groups of patients did not differ with respect to age, neuromuscular performance, bone mineral density, and fear of falling. CONCLUSION: This neuromuscular test battery is a feasible and practical tool because it is brief and economical to perform. However, its efficacy as a predictor of fractures must be tested in additional studies with a long-term follow-up and a larger group of subjects.

Long-term home exercise program: effect in women at high risk of fracture.

OBJECTIVE: To determine whether a better outcome in terms of physical frailty could be achieved with a regular home exercise program in women at high risk of fracture. DESIGN: Prospective long-term observational study. SETTING: Outpatient clinic of physical medicine and rehabilitation. PARTICIPANTS: Women with a history of postmenopausal fractures and an age-adjusted low bone mass, as determined 7 to 12 years earlier. INTERVENTION: Home exercise program. OUTCOME MEASURES: Thirty-three women were followed. The exercise group and control group were compared with regard to fracture rates, episodes of falling, neuromuscular performance (one-leg stance, chair rise, body sway, tandem walk, tapping test), and bone mineral density (BMD). RESULTS: Twenty-five women with a mean age of 73.8+/-5.7 yrs appeared for the investigation. An exercise program had been prescribed in 19 women, and six served as controls. Seven women of the exercise group (36.8%) regularly performed the exercises. No differences between participants of the groups in terms of fracture rates, falling episodes, neuromuscular performance, and BMD were observed. CONCLUSION: It appears that a home exercise program does not affect the outcome of postmenopausal women at high risk of fracture.

[Comparison of manual lymph drainage with physical therapy in complex regional pain syndrome, type I. A comparative randomized controlled therapy study]. / Manuelle Lymphdrainage im Vergleich zur Physiotherapie bei Complex Regional Pain Syndrom Typ I. Randomisierte kontrollierte Therapievergleichsstudie.

Sympathetic blockage and physiotherapy are among the most effective treatment approaches for the complex regional pain syndrome (CRPS). It is important to institute the treatment as early as possible in order to avoid major functional limitations of the affected limb. Unfortunately, there is a paucity of vigorously applied randomised or placebo-controlled trials for these therapeutic approaches. A prospective randomised study of 35 outpatient clinic patients with type I complex regional pain syndrome of the lower extremities lasting less than 6 months is described. One of two treatments, exercise alone or exercise in combination with manual lymph drainage, was applied for six weeks, three times a week, to the affected limb. Clinical and subjective parameters for pain, swelling, temperature, and range of motion were evaluated. Manual lymph drainage was chosen as adequate therapy for oedema reduction, whereas exercise was applied as standard therapy for contracture prophylaxis in reflex sympathetic dystrophy. Both groups were asked not to use analgesics but received extensive instructions for avoiding pain. Significant improvements in clinical parameters were observed in both groups, but no significant effect between treatment groups was found. Pain measurement alone with a verbal rating scale showed a tendency towards greater pain reduction in the group receiving lymph drainage. The results indicate that, during the first 6 months of complex regional pain syndrome type I, manual lymph drainage provides no additional benefit when applied in conjunction with an intensive exercise program.

[Evaluating rehabilitation progress by measuring thigh circumference]. / Beurteilung des Rehabilitationsfortschritts mittels Oberschenkelumfangmessung.

QUESTION: Thigh girth measurements have been widely used to quantify rehabilitation progress following knee surgery, but the correlation between thigh girth and other functional measures has not been investigated. This study intended to investigate whether such a correlation exists. METHODS: 15 women with bilateral osteoarthrosis of the knee participated in this study. Isokinetic knee extensor strength, thigh girth and body mass were measured immediately before, then at six weeks and six months following cementless total knee arthroplasty. RESULTS: The involved side showed clear pre-operative isokinetic knee extensor strength deficits, and slight reductions in thigh girth. Post-operatively, mean strength deficits were reduced, whereas differences in mean thigh girth became lager. Although thigh girth changes correlated well with body mass, they did not correlate with knee extensor strength. CONCLUSION: Changes in thigh girth are mainly due to changes in body mass. Thigh girth measurement is of no use for the quantification of the rehabilitation progress in total knee arthroplasty.

[Translation of the Osteoporosis Quality of Life questionnaire (OQLQ) into German]. / Anwendung des in die deutsche Sprache übersetzten Osteoporosis Quality of Life Questionnaire (OQLQ).

Osteoporosis is a major health problem affecting the quality of life. The Osteoporosis Quality of Life Questionnaire (OQLQ) is a disease-specific measure intended for use in English-speaking countries. As there is a need for measures in non English-speaking countries as well, we translated the OQLQ according to a standardised protocol into the German language. Twenty-five women suffering from osteoporosis were tested in regard of quality of life. The questionnaire appears to be especially suitable for more disabled patients.

[Cold and cryotherapy. A review of the literature on general principles and practical applications]. / Kälte- und Kryotherapie. Eine Literaturübersicht über Grundlagen und praktische Anwendungen.

Cryotherapy increases the threshold of pain and induces physiological changes. It influences hemodynamics (reduction of skin- and muscle temperature through vasoconstriction), metabolism (reduction of ischemia due to hypoxia), and neural control (reduction of nerve conduction velocity and muscle tone). Cryotherapy is indicated mainly in locomotor system related pain. Such pain can be induced by degenerative changes, postoperatively, and during mobilisation of contracted joints. Cryotherapy may be used as short term therapy (less than 15 min) as well as long term therapy (more than 20 min). For maximal efficacy the intensity of application as well as the application medium must be considered. Due to biorhythm, cold application seems to be more effective in the afternoon.

Sacral reflexes: physiology and clinical application.

Sacral reflexes consist of motor responses in the pelvic floor and sphincter muscles evoked by stimulation of sensory receptors in pelvic skin, anus, rectum, or pelvic viscera. These responses may be elicited by physical or electrical stimuli. They have been used in research studies of the pathophysiology of pelvic floor and anorectal disorders and many have been recommended for diagnostic use. These reflexes are described and discussed in this review. More rigorous evaluation of their value in the clinical assessment and care of patients with pelvic floor and sphincter disorders is required. Currently direct comparisons of the value of particular responses are generally not available, and few of these reflexes have proven validity for use in clinical diagnosis.

[Therapy relevant aspects of anatomy, pathophysiology and diagnosis of urinary incontinence in women]. / Therapierelevante Aspekte der Anatomie, Pathophysiologie und Diagnostik der weiblichen Harninkontinenz.

Many aspects of the pathogenesis of urinary incontinence are poorly understood. Most studies show good results for physical therapy for instance for pelvic floor exercises and biofeedback. Unfortunately most of these studies lack an objective diagnostic and neurophysiological assessment. This could be one reason for the strongly divergent therapeutical success rates reported (30 to 90%). We recommend the use of objective parameters, for instance the PAD test with standardized bladder volume and a neurophysiological and short urodynamic assessment as well as subjective parameters [satisfaction with the outcome of treatment measured with the VAS (visual analog scale), documentation of the changes in ADL (activities of daily living)] in future therapeutical studies. A more precise assessment of the pathological cause of the impairment will help to develop optimal therapeutic procedures. Because of poor documentation in the past the analysis of therapeutic failures and the decision if mono-or complex physiotherapy is more appropriate has not been possible. This aspect will become even more important as the cost-effectiveness of treatments becomes a more important issue.

[Nutrition and osteoporosis: a nutritional analysis of women in postmenopause]. / Ernährung und Osteoporose: Eine Ernährungsanalyse bei Frauen in der Postmenopause.

In a cross-sectional study the effects of several nutritional factors on the manifestations of osteoporosis were investigated in 23 postmenopausal women aged 50 to 70 years. Twelve women (group 1) with osteoporosis and eleven healthy control subjects (group 2) were instructed to keep a seven-day nutritional record. Body mass index (BMI) was recorded, and radiological and bone mineral density investigations were undertaken. The daily total energy, protein, fat, carbohydrate, fiber, oxalic acid, calcium, magnesium, phosphorus, sodium, fluoride, zinc, copper, manganese, vitamin C, D, and K intake were analysed within the framework of a nutritional science program. No intergroup differences were observed with regard to total energy intake, nutritional components and BMI; however, age and years since the menopause differed significantly (p < 0.05). The results suggest that the manifestation of osteoporosis in women is influenced to a greater extent by age and years since the menopause than by the distribution of nutritional factors in a normal mixed diet. However, further studies are essential to evaluate the role of dietary composition on the manifestations of osteoporosis.

[Postural disorders in children and adolescents]. / Haltungsstörungen bei Kindern und Jugendlichen.

Posture is defined as the upright well balanced position of an individual person. A postural fault is a posture that deviates from normal alignment without structural limitations. Postural faults are established in adolescence causing pain syndromes in adulthood. Major components of spinal structure and function are reviewed. The dynamics of posture are described. Characteristics and etiology of common postural faults in childhood and adolescence are characterised. Based on standardised diagnostic techniques, principles of how to manage posture and treatment of postural dysfunctions are discussed.