[Proposal for participation in intensive care and emergency medicine studies for patients unable to give informed consent (Cologne Model)]

When conducting clinical trials in intensive care and emergency medicine, physicians, ethics committees, and legal experts have differing views regarding the inclusion of patients who are incapable of giving consent. These different views on the participation of patients who are not capable of giving consent also complicate how clinical trials are prepared and conducted. Based on the results of a literature search, a consensus model (Cologne Model) was developed by physicians performing clinical research, ethics committees, and lawyers in order to provide patients, those scientifically responsible for the study, ethics committees, and probate (guardianship) judges with a maximum of patient safety and legal certainty, while simultaneously enabling scientific research.

Comparative in vivo toxicokinetics of silver powder, nanosilver and soluble silver compounds after oral administration to rats

Silver (Ag; massive, powder and nanoform) and Ag compounds are used in industrial, medical and consumer applications, with potential for human exposure. Uncertainties exist about their comparative mammalian toxicokinetic ('TK') profiles, including their relative oral route bioavailability, especially for Ag massive and powder forms. This knowledge gap impedes concluding on the grouping of Ag and Ag compounds for hazard assessment purposes. Therefore, an in vivo TK study was performed in a rat model. Sprague-Dawley rats were exposed via oral gavage for up to 28 days to silver acetate (AgAc; 5, 55, 175 mg/kg(bw)/d), silver nitrate (AgNO3; 5, 55, 125 mg/kg(bw)/d), nanosilver (AgNP; 15 nm diameter; 3.6, 36, 360 mg/kg(bw)/d) or silver powder (AgMP; 0.35 µm diameter; 36, 180, 1000 mg/kg(bw)/d). Total Ag concentrations were determined in blood and tissues to provide data on comparative systemic exposure to Ag and differentials in achieved tissue Ag levels. AgAc and AgNO3 were the most bioavailable forms with comparable and linear TK profiles (achieved systemic exposures and tissue concentrations). AgMP administration led to systemic exposures of about an order of magnitude less, with tissue Ag concentrations 2-3 orders of magnitude lower and demonstrating non-linear kinetics. The apparent oral bioavailability of AgNP was intermediate between AgAc/AgNO3 and AgMP. For all test items, highest tissue Ag concentrations were in the gastrointestinal tract and reticuloendothelial organs, whereas brain and testis were minor sites of distribution. It was concluded that the oral bioavailability of AgMP was very limited. These findings provide hazard assessment context for various Ag test items and support the prediction that Ag in massive and powder forms exhibit low toxicity potential.

Evaluation of effects-based methods as monitoring tools for assessing ecological impacts of metals in aquatic ecosystems

Effects-based methods (EBMs) are considered part of a more integrative strategy for regulating substances of concern under the European Union Water Framework Directive. In general, EBMs have been demonstrated as useful indicators of effects on biota, although links to population and community-level effects are sometimes uncertain. When EBMs are sufficiently specific and sensitive, and links between measured endpoints and apical or higher level effects are established, they can be a useful tool in assessing effects from a specific toxicant or class of toxicants. This is particularly valuable for toxicants that are difficult to measure and for assessing the effects of toxicant mixtures. This paper evaluates 12 EBMs that have been proposed for potential use in the assessment of metals. Each EBM was evaluated with respect to metal specificity and sensitivity, sensitivity to other classes of toxicants, and the strength of the relationship between EBM endpoints and effects observed at the whole organism or population levels of biological organization. The evaluation concluded that none of the EBMs evaluated meet all three criteria of being sensitive to metals, insensitive to other classes of toxicants, and a strong indicator of effects at the whole organism or population level. Given the lack of suitable EBMs for metals, we recommended that the continued development of mixture biotic ligand models (mBLMs) may be the most effective way to achieve the goal of a more holistic approach to regulating metals in aquatic ecosystems. Given the need to further develop and validate mBLMs, we suggest an interim weight-of-evidence approach that includes mBLMs, macroinvertebrate community bioassessment, and measurement of metals in key macroinvertebrate species. This approach provides a near-term solution and simultaneously generates data needed for the refinement and validation of mBLMs. Once validated, it should be possible to rely primarily on mBLMs as an alternative to EBMs for metals. Integr Environ Assess Manag 2023;19:24-31.  © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

European freshwater silver monitoring data do not suggest a potential European-wide risk

European legislations frequently focus on substances that are of potential concern to human or environmental health, such as "priority substances" under the Water Framework Directive 2000/60/EC ("WFD") that are identified as substances posing a significant risk to or via the aquatic environment. The EU REACH regulation also requires the assessment of the environmental risks of chemicals put on the EU market. To properly assess the potential risk of a substance, high-quality representative monitoring data should be compared with a safe threshold concentration. The objective of this article is to evaluate different publicly available freshwater monitoring data sets for silver and investigate them for a potential European-wide risk according to the methodology used by the European Commission. Most available silver monitoring data sets contain a large proportion of undetected samples with a reported concentration below the limit of quantification (LOQ) of the analytical technique, leading to considerable uncertainty in the data set. For silver, this LOQ is often at or above the safe threshold concentration, and the method used to handle undetected samples during the data processing considerably impacts the data assessment. We demonstrate that for large data sets covering many European countries (and often a wide range of LOQs), the uncertainty in the data set does not allow us to make a general conclusion about European-wide risk. However, by examining the data sets in more detail and assessing three additional country-specific monitoring data sets, we show that silver does not pose a risk to the freshwater environment in several countries. We conclude that the available data sets need careful assessment to account for the values that are below the LOQ, and that there is currently no reliable evidence indicating a European-wide risk for silver in the aquatic environment, meaning it should not be selected as  priority substance under the WFD. Integr Environ Assess Manag 2023;00:1-10. © 2022 SETAC.

O-184 Maternally inherited differences in mitochondrial DNA genotype between ART and spontaneously conceived individuals associate with low birthweight

Study question

Can mitochondrial DNA (mtDNA) variants explain the differences in birthweight between ART and spontaneously conceived (SC) individuals and how do they originate?

Summary answer

Children born after ART carry more frequently a different mtDNA variant composition, both maternally inherited and de novo, which are predictive of their birthweight percentile.

What is known already

Children born after ART show an increased risk of lower birthweight and of developing a mild abnormal cardio-metabolic profile later in life. Variation in the mtDNA associates with overall health in the general population, including cardio-metabolic fitness, and can result in changes in mitochondrial function. We hypothesized that mitochondrial DNA variants could explain the differences in birthweight between ART and SC individuals and that these differences may result from maternal transmission and/or from the ovarian stimulation (OS) used in ART.

Study design, size, duration

We deep-sequenced the mtDNA of 472 individuals of who 283 ART and 189 SC, 182 mother-child pairs and 113 single oocytes from both natural menstrual cycles and OS cycles. The mtDNA was compared between groups and Fisher linear discriminant analysis was used as predictive model for the birthweight percentile.

Participants/materials, setting, methods

Mitochondrial DNA was enriched by long-range PCR and subsequently sequenced on an Illumina platform. mtDNA server and MuTect were used for variant calling for variants with a load higher than 1.5%, versus the reference NC_012920.1. An orthogonally rotated factor analysis was used to reduce the dimensionality of the studied dependent variables in the complex data of the heteroplasmic variants.

Main results and the role of chance

ART individuals carried more frequently haplogroup U4 (p = 0.004) and component analysis indicated that they carry a different mtDNA heteroplasmic variant composition than SC individuals (p = 0.01), driven by non-synonymous protein-coding and rRNA-coding variants. These differences were also predictive of the risk of a lower birthweight percentile, especially for the SC children, together with the absence of haplogroup T, the presence of homoplasmic tRNA-variants, pregnancy-induced hypertension and the embryo culture medium used. The differences in heteroplasmic variation observed in the ART children resulted from both maternal transmission (p = 0.03) and de novo mutagenesis (p = 0.02). Mothers of ART children showed a similar mtDNA genotype as their children and differed in the same variant composition when compared to the mothers of SC children (p = 0.03). Furthermore, the comparison of oocytes from the same donors retrieved in natural menstrual cycles and after one OS cycle showed that OS does not increase de novo mutagenesis. Additionally, clinical parameters such as the total dosage of FSH units, the number of oocytes retrieved, and maternal age did not show any correlation with the differences observed in ART individuals.

Limitations, reasons for caution

This study is observational with no functional tests being performed.

Wider implications of the findings

We demonstrate an association between a lower birthweight percentile and a mtDNA variant composition which is more frequently carried by ART children. These non-disease associated mtDNA variants could cause a suboptimal mitochondrial function affecting the birthweight. Long-term health consequences of these differences remain to be further elucidated.

Trial registration number

Not applicable

POS0852 HIGH DOSE INTRAVENOUS PULSE METHOTREXATE IN REFRACTORY EOSINOPHILIC FASCIITIS: WHAT ARE THE ADVERSE EVENTS?

Background:

Eosinophilic Fasciitis (EF) is a disease of unknown origin initially characterized by limb or trunk edema, and collagenous thickening of the subcutaneous fascia in later stages. Eosinophilia in peripheral blood is commonly observed. Being a rare disease, evidence regarding treatment is mainly based on case series and anecdotal evidence. The mainstay systemic treatment is prednisone, and Methotrexate (MTX) up to doses of 25 mg/week is the leading prednisone-sparing agent. Mycophenolate can be considered in refractory cases. As an alternative we explored the use of intravenous (i.v.) pulse MTX. We already showed this to be a potentially effective and safe treatment option in a prospective single-arm study1, but more data on adverse events (AEs) are needed.

Objectives:

To present an overview of AEs of high dose i.v. pulse MTX in refractory EF.

Methods:

Adult patients with EF based on clinical appearance combined with histology and/or MRI, who were unresponsive to prednisone combined with low-dose MTX or presenting with severe disease, were selected for this retrospective cohort study. Patients received 6-9 monthly infusions of 4 mg/kg MTX followed by oral folinic acid rescue therapy, which is comparable to treatment schedules for trophoblast disease. An additional number of six pulses could be administered in case of a partial effect or flare. Safety data were monitored during each visit and classified according to the Common Terminology Criteria for Adverse Events (CTCAE) from the National Institute of Health (2009).

Results:

Twenty-seven patients (26 with EF, one with deep linear morphea) were included in this study (five males), with a mean age of 59 (sd 11.5) years, based on clinical presentation and histology and/or MRI. Previous treatment data were available for 22 patients of which 21 received oral prednisone (20-60 mg) whether or not combined with low dose MTX and/or UVA1 therapy. All patients reported ≥ 1 AEs at some stage, exactly 100 in total. ‘Gastro-intestinal disorders’ (n=36) and ‘General disorders and administration site conditions’ (n=15) were most common; especially nausea (n=6) and fatigue (n=11). One patient was hospitalized for blood transfusion. In four cases, treatment was discontinued due to AEs (acute kidney injury (AKI), depression, nausea/vomiting, and leukopenia resp.). Each reported AE appeared reversible. The patient with AKI had an MTX level in the toxic range; methotrexate-induced crystal nephropathy seemed the most likely explanation, probably due to a combination of high body weight (and thus high absolute dosage of MTX) and the concomitant use of omeprazole. Oral folinic acid rescue therapy was prolonged, together with 500 cc i.v. fluid, after which kidney function normalized.

Organ systemAEFrequencyGastro-intestinal disordersNausea, oral mucositis, diarrhea, vomiting, abdominal pain, anorexia36General disorders, administration site conditionsMalaise, fatigue15Respiratory, thoracic, mediastinal disordersCough and dyspnea10Skin and subcutaneous tissue disordersSkin hyperpigmentation, hair loss, alopecia, other9Nervous systemHeadache, nerve abducens disorder7Infections and infestinationsSkin, urinary tract, upper respiratory tract, other6Blood, lymphatic system disordersAnemia, leukopenia, pancytopenia4Psychiatric conditionsDepression3Renal, urinary disordersAcute Kidney Injury1Other systems9100

Conclusion:

AEs were common among patients receiving high dose i.v. pulse MTX, especially nausea and fatigue, but were generally mild and reversible in all cases. This is in line with studies performed with patients with trophoblast disease. One episode of reversible AKI occurred that seemed to be related to high body weight and the use of concomitant medication. The safety profile of i.v. pulse MTX thus seems auspicious, but the case of AKI illustrates that further data on safety is needed.

References:

[1]Mertens JS et al. High-dose intravenous pulse methotrexate in patients with eosinophilic fasciitis. JAMA Dermatol 2016; 1(152):1262-5.

Disclosure of Interests:

None declared

Setting a Protective Threshold Value for Silver Toward Freshwater Organisms

Driven by Regulation (EC) No. 1272/2008 and the European Water Framework Directive 2000/60/EC, we have re-evaluated the available chronic freshwater ecotoxicity data for ionic silver (Ag) using strict data quality criteria. In addition, we generated new chronic ecotoxicity data for species potentially sensitive to Ag (the rotifer Brachionus calyciflorus, the cyanobacteria Anabaena flos-aquae, and the aquatic plant Lemna minor) using Ag nitrate as the test substance. The 10% effect concentrations for the most sensitive endpoint per test species were 0.31 µg dissolved Ag/L for B. calyciflorus (population size), 0.41 µg dissolved Ag/L for A. flos-aquae (growth rate), and 1.40 µg dissolved Ag/L for L. minor (root length). We included these values in the set of reliable chronic freshwater data, subsequently covering a total of 12 taxonomic groups and 15 species. Finally, we applied a species sensitivity distribution approach to the data set using various models. The best-fitting model (Rayleigh distribution) resulted in a threshold value protective for 95% of the species of 0.116 µg dissolved Ag/L. This value is considered reliable and conservative in terms of species protection and can be used as a solid basis for setting thresholds for Ag in freshwater after application of an appropriate assessment factor. Furthermore, this value represents reasonable worst-case conditions for bioavailability in European Union surface waters (low hardness and low dissolved organic carbon). Environ Toxicol Chem 2021;40:1678-1693. © 2021 European Precious Metals Federation. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

The effect of polymorphisms in FSHR and FSHB genes on ovarian response: a prospective multicenter multinational study in Europe and Asia

STUDY QUESTION

Does the presence of single nucleotide polymorphisms (SNPs) in the FSH receptor gene (FSHR) and/or FSH beta subunit-encoding gene (FSHB) influence ovarian response in predicted normal responders treated with rFSH?

SUMMARY ANSWER

The presence of FSHR SNPs (rs6165, rs6166, rs1394205) has a statistically significant impact in ovarian response, although this effect is of minimal clinical relevance in predicted normal responders treated with a fixed dose of 150 IU rFSH.

WHAT IS KNOWN ALREADY

Ovarian reserve markers have been a breakthrough in response prediction following ovarian stimulation. However, a significant percentage of patients show a disproportionate lower ovarian response, as compared with their actual ovarian reserve. Studies on pharmacogenetics have demonstrated a relationship between FSHR or FSHB genotyping and drug response, suggesting a potential effect of individual genetic variability on ovarian stimulation. However, evidence from these studies is inconsistent, due to the inclusion of patients with variable ovarian reserve, use of different starting gonadotropin doses, and allowance for dose adjustments during treatment. This highlights the necessity of a well-controlled prospective study in a homogenous population treated with the same fixed protocol.

STUDY DESIGN, SIZE, DURATION

We conducted a multicenter multinational prospective study, including 368 patients from Vietnam, Belgium, and Spain (168 from Europe and 200 from Asia), from November 2016 until June 2019. All patients underwent ovarian stimulation followed by oocyte retrieval in an antagonist protocol with a fixed daily dose of 150 IU rFSH until triggering. Blood sampling and DNA extraction was performed prior to oocyte retrieval, followed by genotyping of four SNPs from FSHR (rs6165, rs6166, rs1394205) and FSHB (rs10835638).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Eligible were predicted normal responder women <38 years old undergoing their first or second ovarian stimulation cycle. Laboratory staff and clinicians were blinded to the clinical results and genotyping, respectively. The prevalence of hypo-responders, the number of oocytes retrieved, the follicular output rate (FORT), and the follicle to oocyte index (FOI) were compared between different FSHR and FSHB SNPs genotypes.

MAIN RESULTS AND THE ROLE OF CHANCE

The prevalence of derived allele homozygous SNPs in the FSHR was rs6166 (genotype G/G) 15.8%, rs6165 (genotype G/G) 34.8%, and rs1394205 (genotype A/A) 14.1%, with significant differences between Caucasian and Asian women (P < 0.001). FSHB variant rs10835638 (c.-211 G>T) was very rare (0.5%). Genetic model analysis revealed that the presence of the G allele in FSHR variant rs6166 resulted in less oocytes retrieved when compared to the AA genotype (13.54 ± 0.46 vs 14.81 ± 0.61, estimated mean difference (EMD) -1.47 (95% CI -2.82 to -0.11)). In FSHR variant rs1394205, a significantly lower number of oocytes was retrieved in patients with an A allele when compared to G/G (13.33 ± 0.41 vs 15.06 ± 0.68, EMD -1.69 (95% CI -3.06 to -0.31)). A significantly higher prevalence of hypo-responders was found in patients with the genotype A/G for FSHR variant rs6166 (55.9%, n = 57) when compared to A/A (28.4%, n = 29), ORadj 1.87 (95% CI 1.08-3.24). No significant differences were found regarding the FORT across the genotypes for FSHR variants rs6166, rs6165, or rs1394205. Regarding the FOI, the presence of the G allele for FSHR variant rs6166 resulted in a lower FOI when compared to the A/A genotype, EMD -13.47 (95% CI -22.69 to -4.24). Regarding FSHR variant rs6165, a lower FOI was reported for genotype A/G (79.75 ± 3.35) when compared to genotype A/A (92.08 ± 6.23), EMD -13.81 (95% CI -25.41 to -2.21).

LIMITATIONS, REASONS FOR CAUTION

The study was performed in relatively young women with normal ovarian reserve to eliminate biases related to age-related fertility decline; thus, caution is needed when extrapolating results to older populations. In addition, no analysis was performed for FSHB variant rs10835638 due to the very low prevalence of the genotype T/T (n = 2).

WIDER IMPLICATIONS OF THE FINDINGS

Based on our results, genotyping FSHR SNPs rs6165, rs6166, rs1394205, and FSHB SNP rs10835638 prior to initiating an ovarian stimulation with rFSH in predicted normal responders should not be recommended, taking into account the minimal clinical impact of such information in this population. Future research may focus on other populations and other genes related to folliculogenesis or steroidogenesis.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by an unrestricted grant by Merck Sharp & Dohme (MSD). N.P.P. reports grants and/or personal fees from MSD, Merck Serono, Roche Diagnostics, Ferring International, Besins Healthcare, Gedeon Richter, Theramex, and Institut Biochimique SA (IBSA). N.L.V. and M.T.H. report consultancy and conference fees from Merck, Ferring, and MSD, outside the submitted work. P.D. has received honoraria for lecturing and/or research grants from MSD, Ferring International, and Merck. D.S. reports grants and/or personal fees from MSD, Ferring International, Merck Serono, Cook, and Gedeon Richter. A.R.N., B.A.M., C.S., J.M., L.H.L., P.Q.M.M., H.T., and S.G. report no conflict of interests.

TRIAL REGISTRATION NUMBER

NCT03007043.

Development of Quantitative Ion Character-Activity Relationship Models to Address the Lack of Toxicological Data for Technology-Critical Elements

Recent industrial developments have resulted in an increase in the use of so-called technology-critical elements (TCEs), for which the potential impacts on aquatic biota remain to be evaluated. In the present study, quantitative ion character-activity relationships (QICARs) have been developed to relate intrinsic metal properties to their toxicity toward freshwater aquatic organisms. In total, 23 metal properties were tested as predictors of acute median effect concentration (EC50) values for 12 data-rich metals, for algae, daphnids, and fish (with and without species distinction). Simple and multiple linear regressions were developed using the toxicological data expressed as a function of the total dissolved metal concentrations. The best regressions were then tested by comparing the predicted EC50 values for the TCEs (germanium, indium, gold, and rhenium) and platinum group elements (iridium, platinum, palladium, rhodium, and ruthenium) with the few measured values that are available. The 8 "best" QICAR models (adjusted r²  > 0.6) used the covalent index as the predictor. For a given metal ion, this composite parameter is a measure of the importance of covalent interactions relative to ionic interactions. Toxicity was reasonably well predicted for most of the TCEs, with values falling within the 95% prediction intervals for the regressions of the measured versus predicted EC50 values. Exceptions included Au(I) (all test organisms), Au(III) (algae and fish), Pt(II) (algae, daphnids), Ru(III) (daphnids), and Rh(III) (daphnids, fish). We conclude that QICARs show potential as a screening tool to review toxicity data and flag "outliers," which might need further scrutiny, and as an interpolating or extrapolating tool to predict TCE toxicity. Environ Toxicol Chem 2021;40:1139-1148. © 2020 SETAC.

Facetime vs. Screentime: Gaze Patterns to Live and Video Social Stimuli in Adolescents with ASD

Atypical eye gaze to social stimuli is one of the most frequently reported and studied social behaviors affected by autism spectrum disorder (ASD). The vast majority of this literature is based on analyses of gaze patterns as participants view social information, such as talking faces, on a computer screen. However, recent results suggest that generalizing gaze behaviors from computer screens to live interactions may not be valid. This study examines between- and within-group differences in gaze behaviors of children with ASD and their neurotypical (NT) peers during a screen-based and a live-interaction task. Results show between-group differences in gaze only for the screen-based, but not the live-interaction task. We also find that gaze behavior of NT children during the screen-based task significantly correlates with their gaze behavior during the live interaction; individuals who direct a higher percentage of gaze to the face in one task also did so in the other task. However, there is no significant relationship between the gaze patterns of children with ASD for those two tasks. These results strongly caution against using gaze of individuals with ASD recorded during screen-based tasks as a proxy for understanding their gaze behavior during live social interactions.

Effects of Silver Nitrate are a Conservative Estimate for the Effects of Silver Nanoparticles on Algae Growth and Daphnia magna Reproduction

Silver (Ag) salts have been shown to be highly toxic to freshwater organisms. There is nevertheless still a high level of uncertainty as to the aquatic effects of Ag nanoparticles (AgNPs), and how these relate to the effects of soluble Ag salts. As part of the substance evaluation for Ag of the European Union Registration, Evaluation, Authorisation, and Restriction of Chemicals regulation, we have generated new data to justify read-across from soluble Ag salts to AgNPs. The aquatic toxicity to algae growth and Daphnia magna reproduction, fate, and behavior of AgNO₃ versus AgNPs were tested and compared. Chloride salts in the test media were replaced with equimolar concentrations of nitrate salts. Total Ag, "conventionally" dissolved Ag (0.45 µm), and "truly" dissolved Ag (3 kDa) were determined. Algae were the most sensitive test species to AgNO₃ (10% effect concentration [EC10] 0.10 µg Ag/L) when expressed as conventionally dissolved Ag. The corresponding value for AgNPs was 0.26 µg/L. For D. magna reproduction, the lowest EC10 values were 3.49 µg Ag/L for AgNO₃ and 33.4 µg Ag/L for AgNPs. Using measured Ag concentrations, AgNO₃ was experimentally shown to be more toxic than AgNPs for all Ag fractions. We explain these observations by a different dissolution behavior of AgNO₃ versus AgNPs. The results provide experimental confirmation that AgNO₃ can be used as a conservative estimate for the aquatic effects of AgNPs at comparable Ag concentrations. Environ Toxicol Chem 2019;38:1701-1713. © 2019 SETAC.

Transformation-dissolution reactions partially explain adverse effects of metallic silver nanoparticles to soil nitrification in different soils

Risk assessment of metallic nanoparticles (NPs) is critically affected by the concern that toxicity goes beyond that of the metallic ion. The present study addressed this concern for soils with silver nanoparticles (AgNPs) using the Ag-sensitive nitrification assay. Three agricultural soils (A, B, and C) were spiked with equivalent doses of either AgNP (diameter = 13 nm) or AgNO₃ . Soil solution was isolated and monitored over 97 d with due attention to accurate Ag fractionation at low (∼10 μg L^-1 ) Ag concentrations. Truly dissolved (<1 kDa) Ag in the AgNO₃ -amended soils decreased with reaction half-lives of 4 to 22 d depending on the soil, denoting important Ag-aging reactions. In contrast, truly dissolved Ag in AgNP-amended soils first increased by dissolution and subsequently decreased by aging, the concentration never exceeding that in the AgNO₃ -amended soils. The half-lives of AgNP transformation-dissolution were approximately 4 d (soils A and B) and 36 d (soil C). The Ag toxic thresholds (10% effect concentrations, milligrams of Ag per kilogram of soil) of nitrification, evaluated at 21 or 35 d after spiking, were similar between the 2 Ag forms (soils A and B) but were factors of 3 to 8 lower for AgNO₃ than for AgNP (soil C), largely corroborating dissolution differences. This fate and bioassay showed that AgNPs are not more toxic than AgNO₃ at equivalent total soil Ag concentrations and that differences in Ag dissolution at least partially explain toxicity differences between the forms and among soils. Environ Toxicol Chem 2018;37:2123-2131. © 2018 SETAC.

How Anxious Do You Think I Am? Relationship Between State and Trait Anxiety in Children With and Without ASD During Social Tasks

Individuals with autism spectrum disorder (ASD) often exhibit increased anxiety, even in non-stressful situations. We investigate general anxiousness (anxiety trait) and responses to stressful situations (anxiety state) in 22 adolescents with ASD and 32 typically developing controls. We measured trait anxiety with standardized self- and parent-reported questionnaires. We used a Biopac system to capture state anxiety via skin conductance responses, mean heart rate and heart rate variability during high- and low-anxiety tasks. Results reveal higher trait anxiety in adolescents with ASD (p < 0.05) and no group difference in state anxiety. Increased parent-reported trait anxiety may predict decreased state anxiety during high-stress conditions. Together, these findings suggest that higher trait anxiety may result in dampened physical responses to stress.

Safe and successful resection of difficult GI lesions using a novel single-step full-thickness resection device (FTRD®)

BACKGROUND AND STUDY AIMS

Classic endoscopic resection techniques (EMR and ESD) are limited to mucosal lesions. In the case of deeper growth into the gut wall and anatomic sites prone to perforation, the novel full-thickness resection device (FTRD^®) opens a new dimension of possibilities for endoscopic resection.

PATIENTS AND METHODS

Sixty patients underwent endoscopic full-thickness resection (eFTR) at our institution. Safety, learning curve, R0 resection rate, and clinical outcome were studied.

RESULTS

In 97% (58/60) of the interventions, the FTRD^®-mounted endoscope reached the previously marked lesion and eFTR was performed (technical success). Full-thickness resection was achieved in 88% of the cases, with an R0 resection on histological examination in 79%. The clinical success rate based on follow-up histology was even higher (88%). Adverse events occurred in 7%. Appendicitis of the residual cecal appendix after eFTR of an adenoma arising in the appendix led to the only post-eFTR surgery (1/58, 2%). Minor bleeding at the eFTR site (2/58, 3%) and an eFTR performed accidently without proper prior deployment of the OTSC^® (1/58, 2%) were successfully treated endoscopically. There was no secondary perforation or eFTR-associated mortality.

CONCLUSIONS

After specific training, eFTR is a feasible, safe, and promising all-in-one endoscopic resection technique. Our data show that eFTR allows complete resection of lesions affecting layers of the gut wall beneath the mucosa with a low risk of adverse events. However, our preliminary results need to be confirmed in larger, controlled studies.

Transplantationsmedizin in der Intensivmedizin

Die Betreuung von Patienten vor und nach einer Organtransplantation gehört zum Gebiet der „speziellen Intensivmedizin“ des jeweiligen Fachbereichs. Die transplantationsspezifische Intensivmedizin setzt daher ein interdisziplinäres Management voraus. Neben der Organprotektion bzw. dem Monitoring von speziellen transplantationsrelevanten Problemen steht die Immunsuppression. Auf das Management mit Immunsuppressiva und von transplantationsassoziierten, intensivmedizinisch relevanten Problemen wird in diesem Kapitel eingegangen. Speziell werden Herz-, Lungen-, Leber-, Nieren- und Stammzelltransplantationen dargestellt.

Spondias tuberosa Arruda (Anacardiaceae), a threatened tree of the Brazilian Caatinga?

Abstract Spondias tuberosa Arr., a fructiferous tree endemic to the northeast Brazilian tropical dry forest called Caatinga, accounts for numerous benefits for its ecosystem as well as for the dwellers of the Caatinga. The tree serves as feed for pollinators and dispersers as well as fodder for domestic ruminants, and is a source of additional income for local smallholders and their families. Despite its vantages, it is facing several man-made and natural threats, and it is suspected that S. tuberosa could become extinct. Literature review suggests that S. tuberosa suffers a reduced regeneration leading to population decrease. At this juncture S. tuberosa cannot be considered threatened according to the International Union for Conservation of Nature Red List Categories and Criteria, as it has not yet been assessed and hampered generative regeneration is not considered in the IUCN assessment. The combination of threats, however, may have already caused an extinction debt for S. tuberosa. Due to the observed decline in tree density, a thorough assessment of the S. tuberosa population is recommended, as well as a threat assessment throughout the entire Caatinga.

Tracking Optical Welding through Groove Modes in Plasmonic Nanocavities

We report the light-induced formation of conductive links across nanometer-wide insulating gaps. These are realized by incorporating spacers of molecules or 2D monolayers inside a gold plasmonic nanoparticle-on-mirror (NPoM) geometry. Laser irradiation of individual NPoMs controllably reshapes and tunes the plasmonic system, in some cases forming conductive bridges between particle and substrate, which shorts the nanometer-wide plasmonic gaps geometrically and electronically. Dark-field spectroscopy monitors the bridge formation in situ, revealing strong plasmonic mode mixing dominated by clear anticrossings. Finite difference time domain simulations confirm this spectral evolution, which gives insights into the metal filament formation. A simple analytic cavity model describes the observed plasmonic mode hybridization between tightly confined plasmonic cavity modes and a radiative antenna mode sustained in the NPoM. Our results show how optics can reveal the properties of electrical transport across well-defined metallic nanogaps to study and develop technologies such as resistive memory devices (memristors).

[Stress fracture or osteochondral lesion of the navicular bone?]

BACKGROUND

An osteochondral lesion of the navicular bone in the foot is rare. Differentiation from a stress fracture is difficult, since both lesions usually present as vague pain in the midfoot in active young adults. However, the typical location differs. SPECT-CT allows an etiological diagnosis to be made. As management differs for the two lesions, a correct diagnosis is important.

CASE DESCRIPTION

A 19-year-old male athlete had pain in the dorsal right midfoot on weight-bearing. A diagnosis of 'stress fracture of the navicular bone' was made on the basis of SPECT-CT. Since conservative therapy did not help, and because the location was atypical for a stress fracture, the diagnosis was revised to 'osteochondral lesion'.

CONCLUSION

The key to the diagnosis of osteochondral lesion is its location in the central proximal third of the navicular bone. Patients with this type of lesion often undergo surgical treatment, whereas conservative therapy is sufficient in case of a stress fracture.

Development of realistic environmental release factors based on measured data: approach and lessons from the EU metal industry

The assessment of environmental exposure and risks associated with the production or use of a substance on an industrial site includes the estimation of the releases to the environment. In the absence of measured release data on the specific substance, a risk assessor would rely on default release factors to the environmental compartments as developed in international, national, or regional context. Because a wide variety of substances, processes, and uses has to be covered, default release factors are as a rule conservative, usually leading to significant overprediction of releases and hence to overpredicted environmental exposure concentrations and risks. In practice, unrealistic and worst-case predictions do not support a more efficient management of releases and risk. The objective of this article is to propose a more realistic approach to characterize the environmental releases from manufacture, processing, and downstream uses of the metals and their compounds. Although developed in the European Union (EU), this approach can also be used in other regions and in other chemical management systems addressing metals. A database consisting of more than 1300 recent (1993-2010), site-specific measured release factors to air and water of 18 different metals from various EU Member States was compiled and used to calculate average and reasonable worst-case release factors for multiple metal manufacture and industrial use processes. The parameters influencing releases to water were found to depend predominantly on life cycle step (manufacture and/or use), the sector and/or the solid-water partition coefficient (K(d)). The release factors can be used as advanced tier instrument in environmental safety assessments, increasing the realism of the estimates while still keeping a sufficient level of conservatism.

Nonlinear superchiral meta-surfaces: tuning chirality and disentangling non-reciprocity at the nanoscale

Circularly polarized light is incident on a nanostructured chiral meta-surface. In the nanostructured unit cells whose chirality matches that of light, superchiral light is forming and strong optical second harmonic generation can be observed.

Propofol sedation for colonoscopy with a new ultrathin or a standard endoscope: a prospective randomized controlled study

BACKGROUND AND STUDY AIMS

The majority of colonoscopies in Germany are performed under conscious sedation. Previous studies reported that pediatric colonoscopes reduce the demand for sedative drugs and may improve cecal intubation. The aim of this study was to compare a new ultrathin and a standard colonoscope in terms of propofol demand during colonoscopy.

PATIENTS AND METHODS

A total of 203 patients were prospectively randomized to undergo colonoscopy with either a 9.5-mm ultrathin (UTC) colonoscope or a standard colonoscope of variable stiffness. Initially, 40 or 60 mg of propofol were administered according to body weight, followed by bolus injections of 20 mg as deemed necessary. Propofol was administered by a separate physician who was blinded to the endoscope used. Sedation levels were defined according to guidelines; pain and complaints were recorded on a numeric rating scale.

RESULTS

Significantly less propofol was required to reach the cecum with the UTC (adjusted mean 94.9 mg [95 % confidence interval (CI) 85.7 - 105.0] vs. 115.3 mg [95 %CI 105.8 - 124.7]; P = 0.003). The level of sedation and pain score were lower with the UTC (sedation level 1 76 % vs. 61 %; P = 0.003; pain score adjusted mean 2.0 [95 %CI 1.7 - 2.4] vs. 2.8 [95 %CI 2.5 - 3.1]; P = 0.001). The rate of ileal and cecal intubation, time to reach the cecum, number of external compressions, withdrawal time, polyp and adenoma detection rate, and patient satisfaction were not different between the two colonoscopes. The time to intubate the ileum was longer with the UTC (1.73 minutes [95 %CI 1.42 - 2.04] vs. 1.22 minutes [95 %CI 0.91 - 1.52]; P = 0.020).

CONCLUSIONS

Use of a new ultrathin colonoscope was associated with reduced propofol consumption, lower patient sedation levels, and less pain than the standard colonoscope, but ileal intubation time was longer.

Value of DCE-MRI and FDG-PET/CT in the prediction of response to preoperative chemotherapy with bevacizumab for colorectal liver metastases

Background:

The purpose of this study was to assess the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and ¹⁸F-fluorodeoxyglucose positron emission tomography computed tomography (FDG-PET/CT) for evaluation of response to chemotherapy and bevacizumab and for prediction of progression-free survival (PFS) in patients with metastatic colorectal cancer (mCRC) with potentially resectable liver lesions.

Methods:

A total of 19 mCRC patients were treated with FOLFOX/FOLFIRI and bevacizumab followed by surgery. Dynamic contrast-enhanced magnetic resonance imaging and FDG-PET/CT were performed before treatment and after cycle 5. PET results were quantified by calculating maximum standardised uptake value (SUV_max) whereas area under the enhancement curve (AUC), initial AUC (iAUC) and the endothelial transfer constant (K^trans) were used to quantify DCE-MRI. Pathological analysis of the resection specimen was performed, including measurement of microvessel density (MVD) and proliferation index.

Results:

Both AUC and iAUC were significantly decreased following bevacizumab therapy (median change of 22% (P=0.002) and 40% (P=0.001) for AUC and iAUC, respectively). Progression-free survival benefit was shown for patients with >40% reduction in K^trans (P=0.019). In the group of radiological responders, the median baseline SUV_max was 3.77 (IQR: 2.88–5.60) compared with 7.20 (IQR: 4.67–8.73) in nonresponders (P=0.021). A higher follow-up SUV_max was correlated with worse PFS (P=0.012). Median MVD was 10.9. Progression-free survival was significantly shorter in patients with an MVD greater than 10, compared with patients with lower MVD (10 months compared with 16 months, P=0.016).

Conclusion:

High relative decrease in K^trans, low follow-up SUV_max and low MVD are favourable prognostic factors for mCRC patients treated with bevacizumab before surgery.

The red mud accident in ajka (hungary): plant toxicity and trace metal bioavailability in red mud contaminated soil

The red mud accident of October 4, 2010, in Ajka (Hungary) contaminated a vast area with caustic, saline red mud (pH 12) that contains several toxic trace metals above soil limits. Red mud was characterized and its toxicity for plants was measured to evaluate the soil contamination risks. Red mud radioactivity (e.g., (238)U) is about 10-fold above soil background and previous assessments revealed that radiation risk is limited to indoor radon. The plant toxicity and trace metal availability was tested with mixtures of this red mud and a local noncontaminated soil up to a 16% dry weight fraction. Increasing red mud applications increased soil pH to maximally 8.3 and soil solution EC to 12 dS m(-1). Shoot yield of barley seedlings was affected by 25% at 5% red mud in soil and above. Red mud increased shoot Cu, Cr, Fe, and Ni concentrations; however, none of these exceed toxic limits reported elsewhere. Moreover, NaOH amended reference treatments showed similar yield reductions and similar changes in shoot composition. Foliar diagnostics suggest that Na (>1% in affected plants) is the prime cause of growth effects in red mud and in corresponding NaOH amended soils. Shoot Cd and Pb concentrations decreased by increasing applications or were unaffected. Leaching amended soils (3 pore volumes) did not completely remove the Na injury, likely because soil structure was deteriorated. The foliar composition and the NaOH reference experiment allow concluding that the Na salinity, not the trace metal contamination, is the main concern for this red mud in soil.

Copper toxicity to bioluminescent Nitrosomonas europaea in soil is explained by the free metal ion activity in pore water

The terrestrial biotic ligand model (BLM) for metal toxicity in soil postulates that metal toxicity depends on the free metal ion activity in solution and on ions competing for metal sorption to the biotic ligand. Unequivocal evidence for the BLM assumptions is most difficult to obtain for native soil microorganisms because the abiotic and biotic compartments cannot be experimentally separated. Here, we report copper (Cu) toxicity to a bioluminescent Nitrosomonas europaea reporter strain that was used in a solid phase-contact assay and in corresponding soil extracts and artificial soil solutions. The Cu(2+) ion activities that halve bioluminescence (EC50) in artificial solutions ranged 10(-5) to 10(-7) M and increased with increasing activities of H(+), Ca(2+) and Mg(2+) according to the BLM concept. The solution based Cu(2+) EC50 values of N. europaea in six contaminated soils ranged 2 × 10(-6) to 2 × 10(-9) M and these thresholds for both solid phase or soil extract based assays were well predicted by the ion competition model fitted to artificial solution data. In addition, solution based Cu(2+) EC50 of the solid phase-contact assay were never smaller than corresponding values in soil extracts suggesting no additional solid phase toxic route. By restricting the analysis to the same added species, we show that the Cu(2+) in solution represents the toxic species to this bacterium.

High throughput optical readout of dense arrays of nanomechanical systems for sensing applications

We present an instrument based on the scanning of a laser beam and the measurement of the reflected beam deflection that enables the readout of arrays of nanomechanical systems without limitation in the geometry of the sample, with high sensitivity and a spatial resolution of few micrometers. The measurement of nanoscale deformations on surfaces of cm(2) is performed automatically, with minimal need of user intervention for optical alignment. To exploit the capability of the instrument for high throughput biological and chemical sensing, we have designed and fabricated a two-dimensional array of 128 cantilevers. As a proof of concept, we measure the nanometer-scale bending of the 128 cantilevers, previously coated with a thin gold layer, induced by the adsorption and self-assembly on the gold surface of several self-assembled monolayers. The instrument is able to provide the static and dynamic responses of cantilevers with subnanometer resolution and at a rate of up to ten cantilevers per second. The instrumentation and the fabricated chip enable applications for the analysis of complex biological systems and for artificial olfaction.