Years For Cd Research Articles

P398 Long term efficacy and safety of ABP, 501 adalimumab biosimilar in inflammatory bowel diseases: preliminary results from the ADASWITCH study

Abstract Background Adalimumab (ADA) biosimilars have been developed to have a much lower financial cost than ADA originator. The aim of this study was to evaluate the long term efficacy and safety of Adalimumab biosimilar ABP501 in naïve or switched Inflammatory Bowel Diseases (IBD) outpatients in Italian non-tertiary IBD centres Methods The ADASWITCH study is a multicentric retrospective observational study. Patients treated with Adalimumab ABP501 and with complete clinical, laboratory and endoscopic data, and a minumum follow-up of, 6 months were included. The primary objective was to evaluate the efficacy (defined as persistence on therapy with Adalimumab ABP501) and the safety (rate of adverse events) occurring during treatment. Results A total of, 117 IBD patients were included:, 83 with Crohn’s disease (CD, 38 F, 45 M, 71% naïve) and, 34 with Ulcerative colitis (UC, 16F, 18 M, 61.8% naïve naïve) were included. ABP, 501 showed more efficacy in maintaining clinical response at, 2 years in CD (64 pts, 77,1%) rather than in UC (22 pts, 64,7%, p=0.001) and in antiTNF (tumor necrosis factor) naïve (63 pts, 78%) rather than in antiTNF experienced patients (27 pts, 72%, p=0.0014), while no difference was seen in efficacy between ADA-switched and ADA-naïve patients. Nine patients (8 CD, 1 UC, overall, 7,7%) had adverse events that led to drug discontinuation. Colonic localisation seems to be a predictor of not sustained clinical response (p=0,002). Conclusion APB, 501 adalimumab biosimilar showed high rates of efficacy and a good safety profile, in both naïve and shifted IBD patients.

S885 Safety of Ustekinumab in Older IBD Patients (≥60 Years): Pooled Safety Analysis Through 5 Years in CD and 2 Years in UC and All Approved Indications

S885 Safety of Ustekinumab in Older IBD Patients (≥60 Years): Pooled Safety Analysis Through 5 Years in CD and 2 Years in UC and All Approved Indications

Biochar-assisted phytoextraction of Cd and Zn by Noccaea caerulescens on a contaminated soil: A four-year lysimeter study

Amendments of biochar, the residual solid of biomass pyrolysis, have been shown to enhance metal phytoextraction from contaminated soils with hyperaccumulating plants in specific situations. In order to investigate this phenomenon over successive harvests in field conditions, two identical undisturbed soil cylinders (1-m2 section × 1.85-m height) were excavated from a contaminated agricultural plot and monitored with instrumented lysimeters. Wood-derived biochar was added at a rate of 5% (w/w) in the first 30 cm of one of the two lysimeters. The Cd/Zn-hyperaccumulator Noccaea caerulescens was then grown for the next four years on both lysimeters. Our results showed that the hyperaccumulating plant was able to remove about 2 g m−2 of Cd and 12–16 g m−2 of Zn within four years, representing about 40% and 4% of the initial Cd and Zn soil contamination, respectively. Biochar amendment improved plant germination and survival and increased root surface density. However, no significant effect of biochar on shoot metal content of N. caerulescens was observed. Mass balances suggested that up to 10% the metal contamination moved from the disturbed Ap horizon to the deeper horizons, particularly in the biochar-amended soil profile. Furthermore, shoot Cd and Zn concentration generally decreased over the successive harvests, together with soil metal availability. Depending on the way to account for this progressive decrease in efficiency, our estimations of the time necessary to remove the excess of metals in the topsoil in these conditions ranged from 11 to 111 years for Cd and from 97 years to an infinite time for Zn. In conclusion, the simultaneous use of N. caerulescens and biochar amendment can lead to a significant removal of specific metallic elements from the topsoil, but the risk of metal movement down the soil profile and the observed decrease in phytoextraction efficiency over time deserve further investigations.

Modeling Covariate-Adjusted Survival for Economic Evaluations in Oncology.

In economic evaluations in oncology, adjusted survival should be generated if imbalances in prognostic/predictive factors across treatment arms are present. To date, no formal guidance has been developed regarding how such adjustments should be made. We compared various covariate-adjusted survival modeling approaches, as applied to the ENDEAVOR trial in multiple myeloma that assessed carfilzomib plus dexamethasone (Cd) versus bortezomib plus dexamethasone (Vd). Overall survival (OS) data and baseline characteristics were used for a subgroup (bortezomib-naïve/one prior therapy). Four adjusted survival modeling approaches were compared: propensity score weighting followed by fitting a Weibull model to the two arms of the balanced data (weighted data approach); fitting a multiple Weibull regression model including prognostic/predictive covariates to the two arms to predict survival using the mean value of each covariate and using the average of patient-specific survival predictions; and applying an adjusted hazard ratio (HR) derived from a Cox proportional hazard model to the baseline risk estimated for Vd. The mean OS estimated by the weighted data approach was 6.85years (95% confidence interval [CI] 4.62-10.70) for Cd, 4.68years (95% CI 3.46-6.74) for Vd, and 2.17years (95% CI 0.18-5.06) for the difference. Although other approaches estimated similar differences, using the mean value of covariates appeared to yield skewed survival estimates (mean OS was 7.65years for Cd and 5.40years for Vd), using the average of individual predictions had limited external validity (implausible long-term OS predictions with > 10% of the Vd population alive after 30years), and using the adjusted HR approach overestimated uncertainty (difference in mean OS was 2.03, 95% CI - 0.17 to 6.19). Adjusted survival modeling based on weighted or matched data approaches provides a flexible and robust method to correct for covariate imbalances in economic evaluations. The conclusions of our study may be generalizable to other settings. ClinicalTrials.gov identifier NCT01568866 (ENDEAVOR trial).

Accumulation and bioavailability of heavy metals in a soil-wheat/maize system with long-term sewage sludge amendments

A long-term field experiment was carried out with a wheat-maize rotation system to investigate the accumulation and bioavailability of heavy metals in a calcareous soil at different rates of sewage sludge amendment. There are significant linear correlations between the contents of Hg, Zn, Cu, Pb, and Cd in soil and sewage sludge amendment rates. By increasing 1 ton of applied sludge per hectare per year in soil, the contents of Hg, Zn, Cu, Pb, and Cd in soil increased by 6.20, 619, 92.9, 49.2, and 0.500 µg kg–1, respectively. For Hg, sewage sludge could be safely applied to the soil for 18 years at an application rate of 7.5 t ha–1 before content exceeded the soil environmental quality standards in China (1 mg kg–1). The safe application period for Zn is 51 years and is even longer for other heavy metals (112 years for Cu, 224 years for Cd, and 902 years for Pb) at an application rate of 7.5 t ha–1 sewage sludge. The contents of Zn and Ni in wheat grains and Zn, Cu, and Cr in maize grains increased linearly with increasing sewage sludge amendment rates. The contents of Zn, Cr, and Ni in wheat straws and Zn, Cu, and As in maize straws were positively correlated with sewage sludge amendment rates, while the content of Cu in wheat straws and Cr in maize straws showed the opposite trend. The bioconcentration factors of the heavy metals in wheat and maize grains were found to be in the order of Zn>Cu>Cd>Hg>Cr=Ni>Pb>As. Furthermore, the bioconcentration factors of heavy metals in wheat were greater than those in maize, indicating that wheat is more sensitive than maize as an indicator plant. These results will be helpful in developing the critical loads for sewage sludge amendment in calcareous soils.

Effect of tree harvest intervals on the removal of heavy metals from a contaminated soil in a field experiment

Four clones of short rotation coppice (SRCs) were investigated for phytoextraction of soil contaminated by risk elements (REs), especially Cd, Pb and Zn. As a main experimental factor, the influence of rotation length on the removal of REs was assessed. The field experiment with two Salix clones (S1 – (Salix schwerinii × Salix viminalis) ×S. viminalis; S2 – S. × smithiana) and two Populus clones (P1 – Populus maximowiczii × Populus nigra; P2 – P. nigra) was established in April 2008 on moderately contaminated soil. For the first time, all clones were harvested in February 2012 (2012<sub>4y</sub>) after 4 years. Subsequently each plot was equally split into halves. The first half of the SRC clones was harvested in February 2014 after 2 years (2014<sub>2y</sub>) and again it was harvested in February 2016 after further 2 years (2016<sub>2y</sub>). The second half was harvested in February 2016 after 4 years (2016<sub>4y</sub>). The results showed that the biomass production for the second 4-year harvest period was significantly higher for all clones but the metal concentration was lower in the mentioned period. 4-year rotation seems to be more advantageous for the phytoextraction than two 2-year rotations. The highest metal removal presented by remediation factors (RFs) per 4 years for Cd (6.39%) and for Zn (2.55%) were found for S2 in the harvest 2016<sub>4y</sub> treatment. Removal of Pb was the highest by P1 clone with very low RF per 4 years (0.04%). Longer rotation is also economically superior.

Modeling Covariate-Adjusted Survival for Economic Evaluations in Oncology

In economic evaluations in oncology, adjusted survival should be generated if imbalances in prognostic/predictive factors across treatment arms are present. To date, no formal guidance has been developed regarding how such adjustments should be made. We compared various covariate-adjusted survival modeling approaches, as applied to the ENDEAVOR trial in multiple myeloma that assessed carfilzomib plus dexamethasone (Cd) versus bortezomib plus dexamethasone (Vd). Overall survival (OS) data and baseline characteristics were used for a subgroup (bortezomib-naive/one prior therapy). Four adjusted survival modeling approaches were compared: propensity score weighting followed by fitting a Weibull model to the two arms of the balanced data (weighted data approach); fitting a multiple Weibull regression model including prognostic/predictive covariates to the two arms to predict survival using the mean value of each covariate and using the average of patient-specific survival predictions; and applying an adjusted hazard ratio (HR) derived from a Cox proportional hazard model to the baseline risk estimated for Vd. The mean OS estimated by the weighted data approach was 6.85 years (95% confidence interval [CI] 4.62–10.70) for Cd, 4.68 years (95% CI 3.46–6.74) for Vd, and 2.17 years (95% CI 0.18–5.06) for the difference. Although other approaches estimated similar differences, using the mean value of covariates appeared to yield skewed survival estimates (mean OS was 7.65 years for Cd and 5.40 years for Vd), using the average of individual predictions had limited external validity (implausible long-term OS predictions with > 10% of the Vd population alive after 30 years), and using the adjusted HR approach overestimated uncertainty (difference in mean OS was 2.03, 95% CI − 0.17 to 6.19). Adjusted survival modeling based on weighted or matched data approaches provides a flexible and robust method to correct for covariate imbalances in economic evaluations. The conclusions of our study may be generalizable to other settings. ClinicalTrials.gov identifier NCT01568866 (ENDEAVOR trial).

The integrated response of torpedograss (Panicum repens) to Cd–Pb co-exposures

In order to explore the technology and models for ecological restoration of bank slopes of water-level-fluctuation (WLF) zones in rivers, lakes, and water reservoirs, investigation was carried out on the morphological and physiological responses of 29 different ecotypes of torpedograss (Panicum repens L.) collected in southern China to Cd and Pb stress. The maximum differences in shoot Cd–Pb accumulation among ecotypes were as large as 8.4 times under Cd–Pb stresses. There were four ecotypes (E4, E8, E9 and E22) that had high accumulation abilities to both Cd and Pb. Under low and high Cd–Pb stresses, the average heavy metal accumulations in shoots of the four ecotypes were 203.7 and 635.8μgpot−1 for Cd, and 182.7 and 390.7μgpot−1 for Pb, respectively. To clean up the heavy metals from soil using the ecotypes, 22 and 14 years for Cd, and 2362 and 2156 years for Pb would be required. Therefore, torpedograss should be viable for prevention or remediation of Cd contaminated water, soil or sediment in WLF zones, but not applicable for Pb contamination. The great differences among the tested genotypes in morphological features in responses to Cd–Pb stresses indicated the occurrence of geographic differentiation in heavy metal tolerance of torpedograss, which was also supported by the results of cluster analysis.

Tu1351 Crohn's Disease Patients Currently or Previously on Natalizumab Can Be Safely and Effectively Switched to Vedolizumab

G A A b st ra ct s multicentre, observational cohort was designed to examine the safety and efficacy of CTP13 infliximab biosimilar in induction and maintenance of remission in Crohn's disease (CD, 108 weeks follow-up) and ulcerative colitis (UC, 54 weeks follow-up). Demographic data were prospectively collected at inclusion. A harmonized, tight monitoring strategy is applied in terms of clinical scores (CDAI, PDAI, pMAYO at each visit), biochemical markers (including CRP, at least every 3 months) and endoscopic/imaging (at least every 12 months) as requested by the National Health Fund. Sera are collected for drug through and antibody measurement at 0, 12, 24 and 52 weeks. Safety data are meticulously registered during follow-up. Results: 90 consecutive IBD patients were included in the present cohort (57 CD patients (27 males) and 33 UC patients (16 males)). Age at disease onset was 26.0 (SD:10.9) years in CD and 30.5 (SD:14.1) years in UC. In CD ileocolonic and perianal disease was present in 40.4% and 37.5% of patients, respectively. 55.2% of UC patients had extensive colitis. 21.4% of CD patients had previous surgery. In CD and UC, 60.4%/ 50% and 55.2%/74.2% of patients received concomitant immunosuppressives and steroids, while 30.4% of CD and 16.1% of UC patients received previous anti-TNFs. At induction, mean CDAI was 289 (SD:107), while MAYO/pMAYO scores were 8.8 (SD 3.1) and 6.4 (SD 2.6) in UC. There was a significant decrease in CDAI after 2 and 6 weeks of treatment compared to baseline (p<0.001, ANOVA-Scheffe). In addition there was a numeric decrease in the mean CRP level (from 23.5mg/L to W2:11.3mg/L and W6:15.3mg/L). There was a significant decrease also in the mean pMAYO score (from 6.4 to (n=16) W2: 3.7 and W6: 3.6) with a numeric decrease in CRP level during induction therapy in UC . 4 allergic reactions occurred, all in patients who had received previous anti-TNF medication. Conclusions: This is the first prospective nationwide cohort examining the safety and efficacy of the biosimilar infliximab in IBD. A significant decrease of disease activity (CDAI and pMAYO) was observed coupled with a decrease in CRP levels during induction with the infliximab biosimilar. A complete analysis of the induction data will be available at the time of congress.

Tu1350 Vedolizumab in the Treatment of IBD: The University of Chicago Experience

G A A b st ra ct s multicentre, observational cohort was designed to examine the safety and efficacy of CTP13 infliximab biosimilar in induction and maintenance of remission in Crohn's disease (CD, 108 weeks follow-up) and ulcerative colitis (UC, 54 weeks follow-up). Demographic data were prospectively collected at inclusion. A harmonized, tight monitoring strategy is applied in terms of clinical scores (CDAI, PDAI, pMAYO at each visit), biochemical markers (including CRP, at least every 3 months) and endoscopic/imaging (at least every 12 months) as requested by the National Health Fund. Sera are collected for drug through and antibody measurement at 0, 12, 24 and 52 weeks. Safety data are meticulously registered during follow-up. Results: 90 consecutive IBD patients were included in the present cohort (57 CD patients (27 males) and 33 UC patients (16 males)). Age at disease onset was 26.0 (SD:10.9) years in CD and 30.5 (SD:14.1) years in UC. In CD ileocolonic and perianal disease was present in 40.4% and 37.5% of patients, respectively. 55.2% of UC patients had extensive colitis. 21.4% of CD patients had previous surgery. In CD and UC, 60.4%/ 50% and 55.2%/74.2% of patients received concomitant immunosuppressives and steroids, while 30.4% of CD and 16.1% of UC patients received previous anti-TNFs. At induction, mean CDAI was 289 (SD:107), while MAYO/pMAYO scores were 8.8 (SD 3.1) and 6.4 (SD 2.6) in UC. There was a significant decrease in CDAI after 2 and 6 weeks of treatment compared to baseline (p<0.001, ANOVA-Scheffe). In addition there was a numeric decrease in the mean CRP level (from 23.5mg/L to W2:11.3mg/L and W6:15.3mg/L). There was a significant decrease also in the mean pMAYO score (from 6.4 to (n=16) W2: 3.7 and W6: 3.6) with a numeric decrease in CRP level during induction therapy in UC . 4 allergic reactions occurred, all in patients who had received previous anti-TNF medication. Conclusions: This is the first prospective nationwide cohort examining the safety and efficacy of the biosimilar infliximab in IBD. A significant decrease of disease activity (CDAI and pMAYO) was observed coupled with a decrease in CRP levels during induction with the infliximab biosimilar. A complete analysis of the induction data will be available at the time of congress.

Tu1349 The Efficacy and Safety of Calcineurin Inhibitors in Inducing and Maintaining Clinical Remission in IBD Patients Commencing Vedolizumab

G A A b st ra ct s multicentre, observational cohort was designed to examine the safety and efficacy of CTP13 infliximab biosimilar in induction and maintenance of remission in Crohn's disease (CD, 108 weeks follow-up) and ulcerative colitis (UC, 54 weeks follow-up). Demographic data were prospectively collected at inclusion. A harmonized, tight monitoring strategy is applied in terms of clinical scores (CDAI, PDAI, pMAYO at each visit), biochemical markers (including CRP, at least every 3 months) and endoscopic/imaging (at least every 12 months) as requested by the National Health Fund. Sera are collected for drug through and antibody measurement at 0, 12, 24 and 52 weeks. Safety data are meticulously registered during follow-up. Results: 90 consecutive IBD patients were included in the present cohort (57 CD patients (27 males) and 33 UC patients (16 males)). Age at disease onset was 26.0 (SD:10.9) years in CD and 30.5 (SD:14.1) years in UC. In CD ileocolonic and perianal disease was present in 40.4% and 37.5% of patients, respectively. 55.2% of UC patients had extensive colitis. 21.4% of CD patients had previous surgery. In CD and UC, 60.4%/ 50% and 55.2%/74.2% of patients received concomitant immunosuppressives and steroids, while 30.4% of CD and 16.1% of UC patients received previous anti-TNFs. At induction, mean CDAI was 289 (SD:107), while MAYO/pMAYO scores were 8.8 (SD 3.1) and 6.4 (SD 2.6) in UC. There was a significant decrease in CDAI after 2 and 6 weeks of treatment compared to baseline (p<0.001, ANOVA-Scheffe). In addition there was a numeric decrease in the mean CRP level (from 23.5mg/L to W2:11.3mg/L and W6:15.3mg/L). There was a significant decrease also in the mean pMAYO score (from 6.4 to (n=16) W2: 3.7 and W6: 3.6) with a numeric decrease in CRP level during induction therapy in UC . 4 allergic reactions occurred, all in patients who had received previous anti-TNF medication. Conclusions: This is the first prospective nationwide cohort examining the safety and efficacy of the biosimilar infliximab in IBD. A significant decrease of disease activity (CDAI and pMAYO) was observed coupled with a decrease in CRP levels during induction with the infliximab biosimilar. A complete analysis of the induction data will be available at the time of congress.

Hospitalisation, surgical and medical recurrence rates in inflammatory bowel disease 2003–2011—A Danish population-based cohort study

ObjectiveThe aim of this study is to evaluate the cumulative probability of recurrence and admission rates in an inflammatory bowel disease (IBD) inception cohort diagnosed in 2003–2004. MethodsData on medications, phenotypes and surgery for 513 individuals with ulcerative colitis (UC, n=300) and Crohn's disease (CD, n=213) were obtained from medical records and linked to population-based health administrative database information. The admission rates and cumulative probability of recurrences were estimated, and the association with the baseline factors and medication was tested. ResultsThe cumulative risk of first recurrence after 1, 5 and 7years was 40%, 63%, and 66% in CD patients and 51%, 75%, and 79% in UC patients, respectively. The cumulative risk of first surgical relapse was 6%, 18%, and 23% at 1, 5 and 7years in CD respectively. One hundred and CD patients (66%) and 142 UC patients (47%) had at least one IBD-related hospitalisation. The hospitalisation rate decreased from 7.0days/person-year in year one to 0.9day at year 5 in CD, and from 4.7days to 0.4days for UC patients. Age above 40, current smoking, stricturing behaviour, and disease localisation (colonic, ileocolonic, and upper-GI) at diagnosis were predictors of recurrence in CD. In UC, age above 40 and former smoker status were predictors of recurrence and left-sided and extensive colitis were predictors of first-time hospitalisation. ConclusionIn an era of improved treatment options, the recurrence rates, but not the surgery or hospitalisation rates, have decreased for CD but not for UC. The phenotypic characteristics at diagnosis predict the risk of recurrence and hospitalisation.

Su1293 Diagnosis of Iron Deficiency in Inflammatory Bowel Diseases by Transferrin Receptor-Ferritin Index

course and intestinal surgery. There is a lack of data regarding diagnostic delay in pediatric IBD patients. We aimed to assess the diagnostic delay in pediatric CD and UC patients and to identifiy risk factors for long diagnostic delay. Methods: Data from the Swiss IBD cohort study were analyzed. Patients were recruited from university centers (68%), regional hospitals (14%), and private practices (18%). Data on diagnostic delay was provided by parents and physician questionnaires. Diagnostic delay was further divided into the time interval from first symptoms to the first consultation with the physician (patient-related interval) and the interval from first physician consultation until IBD diagnosis was established (physician related interval). Long diagnostic delay was defined as delay lying above the 75th percentile. Non-normal data are presented as median, interquartile range [IQR] and range. Results: A total of 100 pediatric CD (37% females) patients and 75 pediatric UC patients (56% females) were included. Age at disease onset was 12 [10 14] years in CD and 11 [7 13] years in UC patients. Diagnostic delay in CD was 4 [2 8] (range 0 82) months with the interval from first symptoms to physician visit of 1 [0 3] (range 0 24) months and from physician visit to diagnosis of 3 [1 9] (range 0 82) months. In UC patients the median diagnostic delay was 2 [1 7] (range 0 52) months with an interval from first symptom onset to physician visit of 0 [0 3] (range 0 36) months and from physician visit to diagnosis of 2 [1 4] (range 0 20) months. Diagnostic delay in CD patients was significantly longer than in UC patients (median 4 vs. 2 months, p = 0.011). Long diagnostic delay was defined as period >8 months in CD and >7 months in UC patients. Neither gender, age at diagnosis, disease location, positive IBD family history, nor provenience (rural vs. non-rural) were associated with long diagnostic delay. Conclusions: The median diagnostic delay in pediatric CD and UC patients in Switzerland is 4 and 2 months, respectively. However, one fourth of pediatric CD patients needs >8 months and one fourth of pediatric UC patients needs >7 months from first symptom onset to IBD diagnosis.

Heavy metal accumulation by poplar in calcareous soil with various degrees of multi-metal contamination: implications for phytoextraction and phytostabilization

The object of this study was to assess the capacity of Populus alba L. var. pyramidalis Bunge for phytoremediation of heavy metals on calcareous soils contaminated with multiple metals. In a pot culture experiment, a multi-metal-contaminated calcareous soil was mixed at different ratios with an uncontaminated, but otherwise similar soil, to establish a gradient of soil metal contamination levels. In a field experiment, poplars with different stand ages (3, 5, and 7 years) were sampled randomly in a wastewater-irrigated field. The concentrations of cadmium (Cd), Cu, lead (Pb), and zinc (Zn) in the poplar tissues and soil were determined. The accumulation of Cd and Zn was greatest in the leaves of P. pyramidalis, while Cu and Pb mainly accumulated in the roots. In the pot experiment, the highest tissue concentrations of Cd (40.76 mg kg(-1)), Cu (8.21 mg kg(-1)), Pb (41.62 mg kg(-1)), and Zn (696 mg kg(-1)) were all noted in the multi-metal-contaminated soil. Although extremely high levels of Cd and Zn accumulated in the leaves, phytoextraction using P. pyramidalis may take at least 24 and 16 years for Cd and Zn, respectively. The foliar concentrations of Cu and Pb were always within the normal ranges and were never higher than 8 and 5 mg kg(-1), respectively. The field experiment also revealed that the concentrations of all four metals in the bark were significantly higher than that in the wood. In addition, the tissue metal concentrations, together with the NH4NO3-extractable concentrations of metals in the root zone, decreased as the stand age increased. P. pyramidalis is suitable for phytostabilization of calcareous soils contaminated with multiple metals, but collection of the litter fall would be necessary due to the relatively high foliar concentrations of Cd and Zn.

Visual acuity changes in cone and cone‐rod dystrophies

The purpose of the study was to evaluate longitudinal visual acuity (VA) changes in cone (CD) and cone-rod dystrophies (CRD) in order to develop recommendations for follow-up strategies and to define an optimal time for potential therapeutic intervention. Patients with clinically defined CD and CRD, who had at least three clinical examinations within a follow-up period of a minimum of 2 years, were included in the study. The observation period was divided into segments: between 1-2 visits and 2-3 visits in intervals of 2 years, and between 3-4 visits in 3-year intervals. Disease history was collected during the baseline examination. Median age of onset, age at first examination, and period between disease onset and 1st visit (latency) were estimated. Medians with 25th and 75th quantile of VA decrease in logMAR for each segment of observation were calculated. The median percentage of VA decrease was also calculated. Initial results of the Tuebingen longitudinal study of VA changes in CRD and CD are presented as medians with 25th and 75th quintiles. Twenty-nine patients (14 men and 15 women) were studied. Nineteen of them had CRD and 10 CD. Median age at the baseline visit was 18 (11, 31) years for CRD and 26 (8, 41.5) years for CD. Median age of disease onset was 9 (8, 25) years for CRD and 7.5 (5, 15) years for CD. The median latency was 6.5 (3; 8.25) years in CD and 4 (2, 10) years in CRD patients. VA in CD and CRD patients was significantly different only during the first visit (p < 0.03). VA decrease was highest in the period between 2-3 visits with a median VA decrease of 36%, for CDR and between 3-4 visits for CD with a median VA decrease of 80%. In the CRD group the rate of VA decline was fairly even over the four visits, whereas in the CD group the decline appeared to progressively increase towards the end of the follow-up. CRD patients were younger than those with CD at a baseline visit and had a longer period of follow-up. A statistically significant difference in VA in CRD and CD was observed at the first ophthalmological examination only. VA decrease was most prominent in the second decade of life in CRD and in third decade in CD patients. CRD was characterized by a more progressive VA decrease than CD. CRD had a high decline of VA over the second and the third examination, whereas VA decline in CD progressed towards the end of follow-up period (fourth examination). These results should be considered when advising and following up such patients on a long-term basis.

Validation of two tropical marine bivalves as bioindicators of mining contamination in the New Caledonia lagoon: Field transplantation experiments

The bioaccumulation and retention capacities of some key local contaminants of the New Caledonia lagoon (Ag, As, Cd, Co, Cr, Cu, Mn, Ni and Zn) have been determined in the oyster Isognomon isognomon and the edible clam Gafrarium tumidum during transplantation experiments. In a first set of experiments, oysters and clams from a clean site were transplanted into contaminated sites. Uptake kinetics determined in the field indicated that for Cr and Cu in oysters and Co, Ni, and Zn in clams, concentrations in transplanted bivalves reached those of resident organisms after 100d, whereas for the other elements, it would require a longer time for transplanted bivalves to reach the same levels as in the resident populations (e.g., up to 3 years for Cd). However, the slow uptake rate for metals observed in the latter transplantation is rather related to low bioavailability of metals at the contaminated sites than to low bioaccumulation efficiency of the organisms. Indeed, results of a second transplantation experiment into two highly contaminated stations indicated a faster bioaccumulation of metals in both bivalves. Results of both transplantations point out that the clam G. tumidum is a more effective bioindicator of mining contamination than I. isognomon, since it is able to bioaccumulate the contaminants to a greater extent. However the very efficient metal retention capacity noted for most elements indicates that organisms originating from contaminated sites would not be suitable for monitoring areas of lower contamination. Hence, geographical origin of animals to be transplanted in a monitoring perspective should be carefully selected.

Study on adsorption and remediation of heavy metals by poplar and larch in contaminated soil

Field experiments at the Shenyang Experimental Station of Ecology were conducted to study the adsorption, accumulation, and remediation of heavy metals by poplar and larch grown in artificially contaminated soil. The soil was spiked with a combination of Cd, Cu, and Zn at concentrations of 1.5, 100, and 200 mg.kg(-1), respectively. The results showed that the biomass of poplar (Populus canadensis Moench) was lower by 26.0% in the soil spiked with a mixture of Cd, Cu, and Zn, compared with the control. Concentrations of Cd in poplar leaf and Cu in poplar roots in the treated soil were 4.11 and 14.55 mg kg(-1), respectively, which are much greater than in corresponding controls. The migration of heavy metals in woody plant body was in the order Cd > Zn > Cu. Poplar had higher metal concentrations in aboveground tissues and a higher biomass compared with larch of the same age and therefore is potentially more suitable for remediation. In the heavy metal-polluted soil of this study, phytoremediation by poplar may take 56 and 245 years for Cd and Cu, respectively, for meeting the soil standards of heavy metals, and the corresponding phytoremediation times by larch would take 211 and 438 years. The research findings could be used as a basis to develop ecological engineering technologies for environmental control and remediation of pollution caused by heavy metals in soils.

Testing the potential of enhanced phytoextraction to clean up NORM and heavy metal contaminated soils

A greenhouse experiment was set up to evaluate the potential of enhanced phytoextraction to clean up U and heavy metal contaminated soils. One soil had a naturally high U concentration; the other soil was impacted by the radium extraction industry. Enhancement of solubility and uptake by plants (ryegrass and Indian mustard) was monitored after addition of 5 chemical amendments: citric acid, ammonium citrate-citric acid mixture, oxalic acid, EDDS and NTA. Solubilisation and uptake were highly influenced by the amendment applied and soil-plant combinations. For U, citric acid, the ammonium citrate-citric acid mixture or EDDS were most effective in increasing U uptake. EDDS was most effective in increasing Cu in mustard and ryegrass and Pb in ryegrass shoots. For other metals, increase in uptake was limited to at most a factor 5. Percentages annually removed with biomass ranged from 0.0002% to 1.52%., and were lowest for U, Cr and Pb and highest for Cd. A targeted 10% reduction in soil contaminant would require 7 years for Cd, 35 and 52 years for Cu and Zn, 203 and 384 years for U and Pb and 9433 years for Cr. Phytoextraction is hence not a feasible technique to decontaminate historically contaminated soils.

A trace metal (Pb, Cd, Zn, Cu) balance for surface waters in the eastern Gotland Basin, Baltic Sea

Trace metal inventories and transboundary fluxes were estimated for the surface waters of the eastern Gotland Basin, and a mass balance for this water body was derived. The study area was delineated by a box which bordered vertically by the sea surface and the halocline and horizontally by the coast of Gotland and the coast of Latvia/Lithuania. For the calculation of the trace metal inventories in the box, a high-resolution sampling was carried out during different seasons. Additional sediment trap studies were performed to calculate the vertical particulate trace metal fluxes through the halocline. The following transboundary fluxes have been estimated: (a) atmospheric input of trace metals; (b) lateral transport from adjacent bodies of surface water; (c) diapycnal fluxes of dissolved trace metals at the halocline; (d) sinking of trace metals, associated with particles, through the halocline, (e) vertical advection through the halocline. The lateral transport into and out of the surface box is important for the metals (Cd, Cu, Zn) with “nutrient-like” behaviour. For particle reactive elements like lead, vertical sedimentation and lateral transport out of the box as much as atmospheric input and lateral input into the box are in the same order of magnitude. Turbulent diapycnal mixing plays a minor role compared to the advective fluxes. The estimated range for the residence times for the region under investigation are ∼ 0.5–1.3 years for Pb; ∼ 2–11 years for Zn, ∼ 7–36 years for Cd and 42–89 years for Cu. This demonstrates that the system reacts very fast for particle reactive elements like Pb, while for copper sedimentation processes are not the preferential sink and can be neglected.