Ketamine in DUID cases in the greater Cologne area

INTRODUCTION

Ketamine is primarily used as an anaesthetic or for analgesics in medical treatment, but due to its dissociative and hallucinogenic effects, abuse has increased in the past years leading to several drug impaired driving cases.

METHODS

Eight DUID (driving under the influence of drugs) cases involving ketamine from two institutes of legal medicine over a period from January 2021 to January 2023 were evaluated. The cases were compared with regard to psychomotor impairments, adverse effects on driving performance and co-consumption of drugs. Analyses of ketamine were carried out by high performance liquid chromatography with diode array detection (HPLC-DAD). Other drugs of abuse were either detected via liquid chromatography with tandem mass spectromety (LC-MS/MS) and/or gas chromatography with (tandem) mass spectrometry (GC-MS(/MS)).

RESULTS

Ketamine plasma concentrations in a range of approx. 100-1200 ng/mL (mean: 510 ng/mL, median: 370 ng/mL) were detected. Co-consumption of at least one substance was ascertained in all cases. Besides driving impairments, recorded psychomotor impairments of the drivers comprised e.g. dilated pupils, missing or delayed pupil reactions, a slurred or decelerated speech, delayed reaction, lack of concentration, vertigo or agitation.

DISCUSSION

The observed peculiarities were in-line with literature data. However, the assessment and differentiation of ketamine-induced impairments was aggravated due to co-consumption of other drugs of abuse or pharmaceuticals in the herein investigated cases. Nevertheless, in two cases impairments can be attributed mainly to ketamine consumption since the co-consumed substances were only detected in low concentrations.

CONCLUSION

The presented cases provide additional data on psychomotor impairments observed in ketamine-related DUID cases. Limiting factors are co-consumption of substances, unknown habituation to drugs and the limited case number. Nevertheless, the results of this study are comparable with existing literature data. Since the abuse of ketamine has increased in the past years, these data will support forensic casework.

Implementation study of the 2021 German guideline for diagnosis and treatment of multiple sclerosis

BACKGROUND

In May 2021, a new guideline on the diagnosis and treatment of multiple sclerosis and related disorders was released in Germany. Since the success of a guideline depends on how it integrates into everyday clinical practice, the German Society for Neurology (DGN) has launched a multimethod implementation project. Here we report on the results based on the consultation version of the guideline.

METHODS

We used qualitative and quantitative data analyses to capture the nature and extent of barriers and facilitating factors to the implementation. We centered on the guideline's chapter A on diagnosis, relapse therapy, and immunotherapy of multiple sclerosis. We performed nine online focus group discussions and a web-based survey and analyzed emails and letters with comments from stakeholders and independent parties that were sent spontaneously or by invitation.

RESULTS

94 neurologists answered the survey, and ≥70% agreed with the recommendations of the guideline on each major content topic. Barriers to implementation were detected in group discussions and written input. The most controversial issues of the guideline were "early treatment", "criteria for starting or switching therapy", "stepwise escalation versus early aggressive treatment", "classification of drugs into three categories of efficacy" and the scenarios on "treatment cessation". Some appreciated the highly structured recommendations, but others felt that the guideline restricts the free choice of therapy, or they were afraid of recourse claims. Some considered the guideline as too cautious regarding treatment initiation, possibly delaying necessary therapies. Others appreciated that conflicts of interests of the guideline's authoring group were minimized and thought that the new guideline is clearer, more extensive and practical.

CONCLUSION

In contrast to the survey, feedback in the focus group discussions and from individuals was diverse and sometimes more critical. Based on the overall feedback rate of about 250 people in relation to the number of 6500 board-certified neurologists in Germany, the overall appreciation of the guideline can only be considered as an indicator and not proof of acceptance. Results of this analysis were incorporated into several adjustments to the final guideline of 2021. Since the guideline is to be updated regularly under the auspices of a "living guideline", active interaction with users will continue to matter and help to improve it.

Ultrashort echo time MRI of the lung in children and adolescents: comparison with non-enhanced computed tomography and standard post-contrast T1w MRI sequences

Objectives

To compare the diagnostic value of ultrashort echo time (UTE) magnetic resonance imaging (MRI) for the lung versus the gold standard computed tomography (CT) and two T1-weighted MRI sequences in children.

Methods

Twenty-three patients with proven oncologic disease (14 male, 9 female; mean age 9.0 + / − 5.4 years) received 35 low-dose CT and MRI examinations of the lung. The MRI protocol (1.5-T) included the following post-contrast sequences: two-dimensional (2D) incoherent gradient echo (GRE; acquisition with breath-hold), 3D volume interpolated GRE (breath-hold), and 3D high-resolution radial UTE sequences (performed during free-breathing). Images were evaluated by considering image quality as well as distinct diagnosis of pulmonary nodules and parenchymal areal opacities with consideration of sizes and characterisations.

Results

The UTE technique showed significantly higher overall image quality, better sharpness, and fewer artefacts than both other sequences. On CT, 110 pulmonary nodules with a mean diameter of 4.9 + / − 2.9 mm were detected. UTE imaging resulted in a significantly higher detection rate compared to both other sequences (p < 0.01): 76.4% (84 of 110 nodules) for UTE versus 60.9% (67 of 110) for incoherent GRE and 62.7% (69 of 110) for volume interpolated GRE sequences. The detection of parenchymal areal opacities by the UTE technique was also significantly higher with a rate of 93.3% (42 of 45 opacities) versus 77.8% (35 of 45) for 2D GRE and 80.0% (36 of 45) for 3D GRE sequences (p < 0.05).

Conclusion

The UTE technique for lung MRI is favourable in children with generally high diagnostic performance compared to standard T1-weighted sequences as well as CT.

Key Points

• Due to the possible acquisition during free-breathing of the patients, the UTE MRI sequence for the lung is favourable in children.

• The UTE technique reaches higher overall image quality, better sharpness, and lower artefacts, but not higher contrast compared to standard post-contrast T1-weighted sequences.

• In comparison to the gold standard chest CT, the detection rate of small pulmonary nodules small nodules ≤ 4 mm and subtle parenchymal areal opacities is higher with the UTE imaging than standard T1-weighted sequences.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08236-7.

Interaction of therapeutic12C ions with bone-like targets: physical characterization and dosimetric effect at material interfaces

Carbon therapy is a promising treatment option for cancer. The physical and biological properties of carbon ions can theoretically allow for the delivery of curative doses to the tumor, while simultaneously limiting risks of toxicity to adjacent healthy structures. The treatment effectiveness can be further improved by decreasing the uncertainties stemming from several sources, including the modeling of tissue heterogeneity. Current treatment plans employ density-based conversion methods to translate patient-specific anatomy into a water system, where dose distribution is calculated. This approach neglects differences in nuclear interactions stemming from the elemental composition of each tissue. In this work, we investigated the interaction of therapeutic carbon ions with bone-like materials. The study concentrated on nuclear interactions and included attenuation curves of 200 and 400 AMeV beams in different types of bones, as well as kinetic energy spectra of all charged fragments produced up to 29 degrees from the beam direction. The comparison between measurements and calculations of the treatment planning system TRiP98 indicated that bone tissue causes less fragmentation of carbon ions than water. Overall, hydrogen and helium particles were found to be the most abundant species, while heavier fragments were mostly detected within 5 degrees from the beam direction. We also investigated how the presence of a soft tissue-bone interface could affect the depth-dose profile. The results revealed a dose spike in the transition region, that extended from the entry channel to the target volume. The findings of this work indicated that the tissue-to-water conversion method based only on density considerations can result in dose inaccuracies. Tissue heterogeneity regions containing bones can potentially produce dose spikes, whose magnitude will depend on the patient anatomy. Dose uncertainties can be decreased by modeling nuclear interactions directly in bones, without applying the tissue-to-water conversion.

Stroke care during the COVID-19 pandemic: experience from three large European countries

In order to cope with the exponentially increasing number of patients infected with SARS-CoV-2, European countries made enormous efforts to reorganize medical assistance and several diseases, including stroke, were particularly impacted. We report the experience of stroke neurologists from three European countries (Italy, France and Germany) that faced the pandemic at diverse time points and with different approaches, depending on their resources and healthcare system organization. Pre-hospital and in-hospital acute stroke pathways were reorganized to prioritize COVID-19 management and, in severely affected regions of Italy and France, stroke care was centralized to a limited number of centers, whereas the remaining stroke units were dedicated to patients with COVID-19. Access to acute stroke diagnostics and time-dependent therapies was limited or delayed because of reduced capacities of emergency services due to the burden of patients with COVID-19. A marked reduction in the number of patients presenting with transient ischaemic attack and stroke was noted in the emergency departments of all three countries. Although we only have preliminary data, these conditions may have affected stroke outcome. These indirect effects of the COVID-19 pandemic could negate the efforts of stroke neurologists over the last few years to improve outcome and reduce mortality of stroke patients. Although the SARS-CoV-2 infection rate is slowing down in Europe, the effects of ending lockdown in the next months are unpredictable. It is important for the European and world stroke community to share what has been learned so far to be plan strategies to ensure stroke care in the future and upcoming challenging times.

Heritable and non-heritable uncommon causes of stroke

Despite intensive investigations, about 30% of stroke cases remains of undetermined origin. After exclusion of common causes of stroke, there is a number of rare heritable and non-heritable conditions, which often remain misdiagnosed, that should be additionally considered in the diagnosis of cryptogenic stroke. The identification of these diseases requires a complex work up including detailed clinical evaluation for the detection of systemic symptoms and signs, an adequate neuroimaging assessment and a careful family history collection. The task becomes more complicated by phenotype heterogeneity since stroke could be the primary or unique manifestation of a syndrome or represent just a manifestation (sometimes minor) of a multisystem disorder. The aim of this review paper is to provide clinicians with an update on clinical and neuroradiological features and a set of practical suggestions for the diagnostic work up and management of these uncommon causes of stroke. The identification of these stroke causes is important to avoid inappropriate and expensive diagnostic tests, to establish appropriate management measures, including presymptomatic testing, genetic counseling, and, if available, therapy. Therefore, physicians should become familiar with these diseases to provide future risk assessment and family counseling.

German validation of the Conners Adult ADHD Rating Scales (CAARS) II: Reliability, validity, diagnostic sensitivity and specificity

Background

The German version of the Conners Adult ADHD Rating Scales (CAARS) has proven to show very high model fit in confirmative factor analyses with the established factors inattention/memory problems, hyperactivity/restlessness, impulsivity/emotional lability, and problems with self-concept in both large healthy control and ADHD patient samples. This study now presents data on the psychometric properties of the German CAARS-self-report (CAARS-S) and observer-report (CAARS-O) questionnaires.

Methods

CAARS-S/O and questions on sociodemographic variables were filled out by 466 patients with ADHD, 847 healthy control subjects that already participated in two prior studies, and a total of 896 observer data sets were available. Cronbach's-alpha was calculated to obtain internal reliability coefficients. Pearson correlations were performed to assess test-retest reliability, and concurrent, criterion, and discriminant validity. Receiver Operating Characteristics (ROC-analyses) were used to establish sensitivity and specificity for all subscales.

Results

Coefficient alphas ranged from .74 to .95, and test-retest reliability from .85 to .92 for the CAARS-S, and from .65 to .85 for the CAARS-O. All CAARS subscales, except problems with self-concept correlated significantly with the Barrett Impulsiveness Scale (BIS), but not with the Wender Utah Rating Scale (WURS). Criterion validity was established with ADHD subtype and diagnosis based on DSM-IV criteria. Sensitivity and specificity were high for all four subscales.

Conclusion

The reported results confirm our previous study and show that the German CAARS-S/O do indeed represent a reliable and cross-culturally valid measure of current ADHD symptoms in adults.

Abstract B66: Deep TLR PrimedTM T cells induce potent antitumor activity without systemic toxicity

TLR7 agonists augment immune responses in the tumor microenvironment (TME), primarily through antigen presenting cell (APC) engagement, enhancement of antigen presentation and T cell costimulation. However, multiple TLR agonists have displayed considerable toxicities upon systemic administration. To circumvent this problem, we developed a T cell-mediated delivery system of TLR7 agonists that can target the TME and lymphoid organs to maximize efficacy while avoiding systemic toxicities. Torque has developed the Deep PrimedTM T-cell therapy technology to surface-tether immunomodulators to multitargeted T cells (MTCs) specific for tumor-associated antigens (TAAs) before adoptive transfer. These Deep PrimedTM T cells target multiple tumor antigens and direct the stimulatory activity of cytokines or small-molecule immunomodulators within the tumors but not in circulation. To create Deep PrimedTM MTCs loaded with TLR7 agonists, we screened several liposomal formulations containing two different TLR7 agonists. To determine the best liposome formulations, TLR7 agonists and liposomal formulations were screened for optimal T-cell loading and viability as well as drug release by HPLC both before and after cell freeze and thaw. Liposome formulations with desired characteristics were then tethered to antigen-specific murine TCR-transgenic CD8 T cells to generate Deep TLR Primed T cells. Following ACT into immunocompetent syngeneic tumor-bearing animals, various Deep Primed T-cell products were evaluated for immune cell activation and efficacy by survival and tumor growth inhibition. Multiple liposomal formulations of TLR7 agonist delivered drug onto MTCs with minimal effect on viability and proliferative capacity. However, drug release over time varied considerably with liposome formulation. Additionally, the TLR7 agonist affected drug release after cell freeze and thaw. In vivo, both the TLR7 agonist and liposomal formulation contributed to the efficacy of the Deep TLR Primed T cells in immunocompetent syngeneic tumor-bearing mice. Optimal liposome liposomal formulations tethered to cells inhibited tumor growth significantly more than ACT of T cells alone or combined with systemically delivered TLR agonists. In conclusion, we found select liposomal formulations successfully delivered TLR7 agonist onto MTCs with low toxicity and exhibited controlled drug release. Furthermore, once the agonist was loaded onto MTCs it was not significantly released after cell freeze and thaw. This formulation stability and extended release will be critical for product safety and efficacy. In vivo, Deep TLR Primed T cells displayed superior efficacy and similar safety compared to T cells alone. Deep TLR PrimedTM tumor antigen-specific autologous T cells have the potential to treat a wide variety of tumors and their distant metastases, to turn a cold tumor hot, enabling a new immunotherapy treatment.

Citation Format: Nathan Westcott, Austin Boesch, Vasily Rybakin, Ji Young Hwang, Kira Jørgensen, Rasmus Lassen, Martin Kraemer, Martin Bak, Gael Veiga, Jonas Bruun, Carlos Tassa, Harrison Rodts, Manny Sequeira, Karsten Sauer, Thomas Andresen. Deep TLR PrimedTM T cells induce potent antitumor activity without systemic toxicity [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B66.

High-Sensitivity Dry Rehydratable Film Method for Enumeration of Coliforms in Dairy Products: Collaborative Study

A dry-film coliform count plate that is inoculated with 5 mL sample was compared with the Violet Red Bile Agar plate method in a collaborative study by 18 laboratories. Products analyzed were 2% milk, chocolate milk, cream, vanilla ice cream, cottage cheese, and cheese. Collaborators tested blind duplicate uninoculated samples and samples inoculated at low, medium, and high level. Significantly (P&lt; 0.05) higher numbers of coliforms were recovered by the dry-film method from 2% milk samples at the 3 inoculum levels, the chocolate milk at the low- and high-inoculum levels, and the cream at the high-inoculum level. Significantly higher counts were obtained by the agar method for cottage cheese samples at the low-inoculum level. The repeatability standard deviation for the dry-film method was significantly higher for the high-inoculum level chocolate milk sample and the medium-inoculum level cottage cheese. The same statistic was significantly higher for the agar method at all 3 inoculum levels in the 2% milk and the medium-inoculum level cream. The high-sensitivity dry rehydratable film method for enumeration of coliforms in dairy products has been adopted first action by AOAC INTERNATIONAL.

Backscattered electron emission after proton impact on gold nanoparticles with and without polymer shell coating

This work aims at measuring experimentally proton induced secondary electron energy spectra after interaction with gold nano particles (GNPs) and polymer-coated GNPs. Backscattered electron energy spectra were collected over a 0 to 1000 eV energy range using a retarding field analyzer (RFA). This paper presents the spectra obtained for proton beam energies of 0.5 and 2 MeV and diameter 2.5 and 3.8 nm GNPs. The spectra were also measured for 3.8 nm GNPs after 5 and 10 MeV proton irradiations. GNPs were deposited on a 100 nm carbon film. Each experimental spectrum was compared with dedicated simulations based on existing numerical models used in the TRAX and Geant4 Monte Carlo codes. For 100 nm carbon target, good agreement between experimental, TRAX and Geant4 simulation results can be observed. For 3.8 nm GNPs, the TRAX simulations reproduce with good agreement the electron energy spectra produced after 0.5, 2, 5 and 10 MeV proton irradiations, while Geant4 spectra display a lower secondary electron yield at low energy (<600 eV) for all the studied energies. This underestimation can mostly be explained by the 790 eV threshold applied in the condensed history model used by Geant4 which impacts the secondary electron energy distribution. Results obtained for carbon and gold targets highlight the impact of the secondary electron production threshold for proton ionization process considered in condensed history models. The experimental results demonstrate that the single interaction approach used in TRAX is adapted to reproduce secondary electron emission from GNPs. On the other hand, the standard electron generation threshold implement in G4BetheBlochModel and G4BraggModel condensed-history models used in Geant4 is not adapted to reproduce low energy electron emission in gold targets. Finally, the results highlight that the GNP coating leads to a decrease of the electron yield and mostly affects low energy electrons (<500 eV) emitted from GNPs.

Experimental measurements validate the use of the binary encounter approximation model to accurately compute proton induced dose and radiolysis enhancement from gold nanoparticles

In protontherapy, it has been suggested that nanoparticles of high-Z material like gold (GNP) could be used as radiosensitizers. The origin of this enhancement phenomenon for proton radiation is not yet well understood and additional mechanistic insights are required. Previous works have highlighted the good capabilities of TRAX to reproduce secondary electron emission from gold material. Therefore, TRAX cross sections obtained with the binary encounter approximation (BEA) model for proton ionization were implemented within Geant4 for gold material. Based on the TRAX cross sections, improved Geant4 simulations have been developed to investigate the energy deposition and radical species production around a spherical gold nanoparticle (5 and 10 nm in diameter) placed in a water volume during proton irradiation. Simulations were performed for incident 2 MeV proton. The dose enhancement factor and the radiolysis enhancement factor were quantified. Results obtained with the BEA model were compared with results obtained with condensed-history models. Experimental irradiation of 200 nm gold films were performed to validate the secondary electron emission reproduction capabilities of physical models used in Monte Carlo (MC) simulations. TRAX simulations reproduced the experimental backscattered electron energy spectrum from gold film with better agreement than Geant4. Results on gold film obtained with the BEA model enabled to estimate the electron emission from GNPs. Results obtained in our study tend to support that the use of the BEA discrete model leads to a significant increase of the dose in the near vicinity of GNPs (<20 nm), while condensed history models used in Geant4 seem to overestimate the dose and the number of chemical species for increasing distances from the GNP. Based on discrete BEA model results, no enhancement effect due to secondary electron emitted from the GNP is expected if the GNP is not in close proximity to key cellular functional elements (DNA, mitochondria…).

Cerebrospinal fluid findings in reversible cerebral vasoconstriction syndrome: a way to differentiate from cerebral vasculitis?

Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by an acute onset of severe headache and multi-focal segmental vasoconstriction of cerebral arteries resolving within 12 weeks. Diagnostic criteria include normal or near-normal findings in cerebrospinal fluid (CSF) analysis, especially leucocyte levels < 10/mm³. Distinguishing RCVS from primary angiitis of the central nervous system (PACNS) is essential to avoid unnecessary and sometimes unfavourable immunosuppressive treatment. We reviewed retrospectively the clinical and diagnostic data of 10 RCVS patients who presented in our neurological department from 1 January 2013 to February 2017. The main purpose was to verify whether CSF leucocyte counts < 10/mm³ serve to discriminate RCVS from PACNS. Five of six patients who underwent lumbar puncture presented with CSF leucocyte levels ≥ 10/mm³. Two patients had a history of misinterpretation of CSF pleocytosis as cerebral vasculitis and of immunosuppressive treatment. A complete restitution of cerebral vasoconstriction was evident in all. No patient had further cerebral strokes or bleedings without immunosuppressive treatment over more than 12 weeks. Despite the established diagnostic criteria, RCVS can manifest with CSF leucocyte levels > 10/mm³. Careful anamnesis and the response of 'vasculitis-like angiography' to nimodipine given as a test during angiography and as oral medication are key to differentiate RCVS from cerebral vasculitis.

Visualization and Classification of Deeply Seated Collateral Networks in Moyamoya Angiopathy with 7T MRI

BACKGROUND AND PURPOSE

Collateral networks in Moyamoya angiopathy have a complex angioarchitecture difficult to comprehend on conventional examinations. This study aimed to evaluate morphologic patterns and the delineation of deeply seated collateral networks using ultra-high-field MRA in comparison with conventional DSA.

MATERIALS AND METHODS

Fifteen white patients with Moyamoya angiopathy were investigated in this prospective trial. Sequences acquired at 7T were TOF-MRA with 0.22 × 0.22 × 0.41 mm³ resolution and MPRAGE with 0.7 × 0.7 × 0.7 mm³ resolution. Four raters evaluated the presence of deeply seated collateral networks and image quality in a consensus reading of DSA, TOF-MRA, and MPRAGE using a 5-point scale in axial source images and maximum intensity projections. Delineation of deeply seated collateral networks by different imaging modalities was compared by means of the McNemar test, whereas image quality was compared using the Wilcoxon signed-rank test.

RESULTS

The relevant deeply seated collateral networks were classified into 2 categories and 6 pathways. A total of 100 collateral networks were detected on DSA; 106, on TOF-MRA; and 73, on MPRAGE. Delineation of deeply seated collateral networks was comparable between TOF-MRA and DSA (P = .25); however, both were better than MPRAGE (P < .001).

CONCLUSIONS

This study demonstrates excellent delineation of 6 distinct deeply seated collateral network pathways in Moyamoya angiopathy in white adults using 7T TOF-MRA, comparable to DSA.

Experimental Evaluation of a Cell Module for Hybrid Liver Support

Aim of the study was to evaluate a hybrid liver support system in a porcine model of acute liver failure, after hepatectomy. Pigs with a body weight of 70±18 kg underwent total hepatectomy and porto - cavo - caval shunting as well as ligation of the bile duct and the hepatic artery. Control animals were connected to the system (including capillary membrane plasma separation) containing a four compartment bioreactor with integral oxygenation and decentralized mass exchange but without liver cells. The treatment group received hybrid liver support with the same system including 370±42 g primary isolated porcine parenchymal liver cells in co-culture with hepatocyte nursing cells, tissue engineered to liver- like structures at high density. Treatment started after complete recovery from anesthesia and was performed continuously. A positive influence on peripheral vascular resistance and a reduced need of catecholamine dosage was observed in the treatment group. Hybrid liver support with a cell module upscaled for clinical application significantly prolonged survival time in animals after hepatectomy with the longest survival being 26 hours in the control group an 57 hours in the treatment group.

Perception of emotional prosody in adults with attention deficit hyperactivity disorder

OBJECTIVE

Attention deficit hyperactivity disorder (ADHD) is associated with social conflicts. The purpose of this study was to explore domains of social cognition in adult patients with ADHD.

METHODS

The assessment of social cognition was based on established neuropsychological tests: the Tübinger Affect Battery (TAB) for prosody and the Cambridge Behaviour Scale (CBS) for empathy. The performance of adults with ADHD (N = 28) was compared with the performance of a control group (N = 29) matched according to basic demographic variables.

RESULTS

Treatment-naïve adults with ADHD showed deficits in emotional prosody (P = 0.02) and in the ability to empathize (P < 0.02) independent of executive functioning. In particular, their ability to perceive angry feelings was found to be compromised (P = 0.04). When emotional prosody was considered in relation to facial expressions, patients and controls showed no impairments (P > 0.2). No gender differences concerning social cognitive skills were detected.

CONCLUSIONS

ADHD is associated with social cognition impairments involving both emotional prosody and empathy.

Ecosystem sentinels for climate change? Evidence of wetland cover changes over the last 30 years in the tropical Andes

While the impacts of climate change on individual species and communities have been well documented there is little evidence on climate-mediated changes for entire ecosystems. Pristine alpine environments can provide unique insights into natural, physical and ecological response to climate change yet broad scale and long-term studies on these potential 'ecosystem sentinels' are scarce. We addressed this issue by examining cover changes of 1689 high-elevation wetlands (temporarily or perennial water-saturated grounds) in the Bolivian Cordillera Real, a region that has experienced significant warming and glacier melting over the last 30 years. We combined high spatial resolution satellite images from PLEIADES with the long-term images archive from LANDSAT to 1) examine environmental factors (e.g., glacier cover, wetland and watershed size) that affected wetland cover changes, and 2) identify wetlands' features that affect their vulnerability (using habitat drying as a proxy) in the face of climate change. Over the (1984-2011) period, our data showed an increasing trend in the mean wetland total area and number, mainly related to the appearance of wet grassland patches during the wetter years. Wetland cover also showed high inter-annual variability and their area for a given year was positively correlated to precipitation intensities in the three months prior to the image date. Also, round wetlands located in highly glacierized catchments were less prone to drying, while relatively small wetlands with irregularly shaped contours suffered the highest rates of drying over the last three decades. High Andean wetlands can therefore be considered as ecosystem sentinels for climate change, as they seem sensitive to glacier melting. Beyond the specific focus of this study, our work illustrates how satellite-based monitoring of ecosystem sentinels can help filling the lack of information on the ecological consequences of current and changing climate conditions, a common and crucial issue especially in less-developed countries.

Ventricular Microaneurysms in Moyamoya Angiopathy Visualized with 7T MR Angiography

The pathophysiologic role of hemodynamic alteration to peripheral vessels in Moyamoya angiopathy and the formation of microaneurysms remains unclear. The purpose of this study was to investigate microaneurysms in collateral Moyamoya vessels by using 7T ultra-high-field MR imaging. Ten patients with Moyamoya disease were evaluated with TOF-MRA at 7T acquired with 0.22 × 0.22 × 0.41 mm(3) resolution. In 10 patients, 4 microaneuryms located in the ventricles were delineated. The mean diameters of collateral vessels and microaneurysms arising from those vessels were 0.87 mm (range, 0.79-1.07 mm) and 0.80 mm (range, 0.56-0.96 mm), respectively. In 1 case with follow-up scans 6 months after a direct extracranial-intracranial bypass operation, the microaneurysm disappeared. Ventricular microaneurysms in Moyamoya angiopathy collateral vessels, inaccessible by conventional imaging techniques, can be detected by 7T TOF-MRA.

UTLS water vapour from SCIAMACHY limb measurementsV3.01 (2002-2012)

The SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) aboard the Envisat satellite provided measurements from August 2002 until April 2012. SCIAMACHY measured the scattered or direct sunlight using different observation geometries. The limb viewing geometry allows the retrieval of water vapour at about 10-25 km height from the near-infrared spectral range (1353-1410 nm). These data cover the upper troposphere and lower stratosphere (UTLS), a region in the atmosphere which is of special interest for a variety of dynamical and chemical processes as well as for the radiative forcing. Here, the latest data version of water vapour (V3.01) from SCIAMACHY limb measurements is presented and validated by comparisons with data sets from other satellite and in situ measurements. Considering retrieval tests and the results of these comparisons, the V3.01 data are reliable from about 11 to 23 km and the best results are found in the middle of the profiles between about 14 and 20 km. Above 20 km in the extra tropics V3.01 is drier than all other data sets. Additionally, for altitudes above about 19 km, the vertical resolution of the retrieved profile is not sufficient to resolve signals with a short vertical structure like the tape recorder. Below 14 km, SCIAMACHY water vapour V3.01 is wetter than most collocated data sets, but the high variability of water vapour in the troposphere complicates the comparison. For 14-20 km height, the expected errors from the retrieval and simulations and the mean differences to collocated data sets are usually smaller than 10 % when the resolution of the SCIAMACHY data is taken into account. In general, the temporal changes agree well with collocated data sets except for the Northern Hemisphere extratropical stratosphere, where larger differences are observed. This indicates a possible drift in V3.01 most probably caused by the incomplete treatment of volcanic aerosols in the retrieval. In all other regions a good temporal stability is shown. In the tropical stratosphere an increase in water vapour is found between 2002 and 2012, which is in agreement with other satellite data sets for overlapping time periods.

Cerebral vasculitis in adults: what are the steps in order to establish the diagnosis? Red flags and pitfalls

Cerebral vasculitis is a rare cause of juvenile stroke. It may occur as primary angiitis of the central nervous system (PACNS) or as CNS manifestation in the setting of systemic vasculitis. Clinical hints for vasculitis are headache, stroke, seizures, encephalopathy and signs of a systemic inflammatory disorder. Diagnostic work-up includes anamnesis, whole body examination, laboratory and cerebral spinal fluid (CSF) studies, magnetic resonance imaging (MRI), angiography and brain biopsy. Due to the rarity of the disease, exclusion of more frequent differential diagnoses is a key element of diagnostic work -up. This review summarizes the steps that lead to the diagnosis of cerebral vasculitis and describes the red flags and pitfalls. Despite considering the dilemma of angiography-negative vasculitis and false-negative brain biopsy in some cases, it is important to protect patients from 'blind' immunosuppressive therapy in unrecognized non-inflammatory differential diagnosis.

Postoperative changes in the superficial temporal artery and the external carotid artery duplex sonography after extra-intracranial bypass surgery in European Moyamoya disease

INTRODUCTION

Despite Duplex ultrasonography being a noninvasive, easily repeatable, readily available and economical tool, this examination and its normal ranges are rarely described in Moyamoya disease (MMD).

METHODS

Duplex ultrasonography examinations of the superficial temporal artery (STA) and external carotid artery (ECA) were performed preoperatively, postoperatively (within 30 days) and as follow-up exams (6 months postoperatively) after 32 cerebral revascularization procedures in 20 European patients with MMD.

RESULTS

A significant higher mean diastolic flow of STA compared to preoperative values was found in postoperative (p<.000) and follow-up exams (p<.001) in Duplex ultrasonography. Postoperative and follow-up Duplex sonography of STA also showed a significantly higher mean systolic flow compared to preoperative values (p<.05 and p<.05). Also ECA showed significantly changes after bypass surgery (p<.05).

CONCLUSION

Duplex ultrasonography of STA is a reliable and non-invasive tool to investigate hemodynamic changes after bypass surgery and to detect bypass patency in European patients with MMD.

A diminished serotonin level influences the performance in a modified AX-continuous performance task in adult ADHD

Introduction

Attention deficit disorder (ADHD) is a psychiatric disorder, which is characterized by deficits of executive functions (EF) and impulsivity. Whereas a variety of studies on the involvement of the dopaminergic system in ADHD exists, the impact of the serotonergic system to EF in ADHD in adults is underinvestigated.

Aims

To ascertain the effects of rapid tryptophan depletion (RTD) and the resultant reduction of the central nervous levels of serotonin on the EF of male adult patients with ADHD.

Methods

20 ADHD patients and 20 healthy controls completed the RTD test on one day and a placebo on another day in a double-blind within subject crossover design.- In addition, the subtest alertness of the TAP and a modified Version of the Continuous performance test (AX-CPT) with three stimulus conditions (AX, AY, BX) were administered.

Results

Statistical analysis revealed significant shorter reaction times, more errors and more omission errors in the ADHD group in the AX-CPT. The omissions error rate increased in both groups in the RTD condition but not in the placebo condition. Statistical analyses did not yield any significant differences between groups in the subtest alertness and no significant interaction of group and effect of the RTD condition could be observed.

Conclusions

In addition to higher impulsivity of patients with ADHD as reflected by shorter reaction times and higher error rates, the results of the present study imply an involvement of the serotonergic system as reflected by RTD in sustained and selective attention.

Ophthalmological findings in children and adolescents with Silver-Russell syndrome

AIM

To evaluate ophthalmological findings in children with Silver-Russell syndrome (SRS).

METHODS

An ophthalmological evaluation including visual acuity (VA), refraction, strabismus, near point of convergence (NPC), slit-lamp examination, ophthalmoscopy, axial length measurements and full-field electroretinogram was performed on 18 children with SRS (8 girls, 10 boys; mean age 11.6 years). Fundus photographs were taken for digital image analysis. Data were compared with data on an age- and gender-matched reference group (ref) of school children (n=99).

RESULTS

Seventeen out of 18 children with SRS had ophthalmological abnormalities. Best corrected VA of the best eye was <0.1 log of the minimal angle of resolution in 11 children (ref n=98) (p<0.0001), and 11 children had refractive errors (ref n=33) (p=0.05). Anisometropia (≥1 dioptre) was noted in three of the children (ref n=3) (p=0.046). Subnormal stereo acuity and NPC were found in 2/16 (ref=0) (p=0.02). The total axial length in both eyes was shorter compared with that in controls (p<0.006 and p<0.001). Small optic discs were found in 3/16, large cup in 3/16 and increased tortuosity of retinal vessels in 4/13 children with SRS.

CONCLUSION

Children with SRS, who are severely intrauterine growth retarded, show significant ophthalmological abnormalities. Based on the present findings, ophthalmological examination is recommended in children with SRS.

Social cognition in attention-deficit hyperactivity disorder (ADHD)

Attention-deficit hyperactivity disorder (ADHD) is associated with a range of cognitive deficits and social cognition impairments, which might be interpreted in the context of fronto-striatal dysfunction. So far only few studies have addressed the issue of social cognition deficits in ADHD.

METHOD

Medline and Psyclit searches were performed for a 30-year period (1979-2009) using the words 'ADHD' and 'social cognition', 'theory of mind', 'prosody', 'face perception', 'humour' or 'social information processing'. Inclusion criteria consisted of a diagnosis according to DSM as well as the inclusion of a control group or a follow-up assessment following the treatment with methylphenidate.

RESULTS

ADHD is clearly associated with social cognition impairments involving emotional face and prosody perception. Although the database is sparse so far, there is some evidence for theory of mind deficits and reduced empathy in ADHD.

CONCLUSIONS

In summary, the social cognition impairments are consistent with fronto-striatal dysfunction in ADHD, but other functional networks of brain areas also appear to be implicated.

Economic benefit of crop pollination by bees: a case of Kakamega small-holder farming in western Kenya

In most developing countries, crop production is by small scale farmers, who mainly produce for their own consumption and the extra for market. Pollination in such systems is unmanaged and is usually incidental, supported by nearby ecosystems. One of the reasons of not managing pollination is the lack of understanding of its economic value. The "public-good" nature of pollination in these systems also discourages individual initiatives intended to conserve pollinators. We evaluate the economic returns from bee pollination in small-holder farming systems. To do this we apply the factor of production method, a form of revealed preferences methods available for valuing ecosystem services. Our analyses show that bee pollination enhances the yield of most crops grown in the farmland and improves immensely the quality of produce. Almost 40% of the annual value of crops under consideration represented the net returns derived from bee pollination. More than 99% of this benefit is attributed to pollination by feral bees. We provide in-depth valuation of pollination service and discuss applicability and limitations of the factor of production method in developing countries.

Perioperative adjuvant therapy with infliximab in complicated anal Crohn's disease

PURPOSE

Infliximab may represent an adjuvant to surgical therapy in patients with severe anal Crohn's disease as it has been shown to affect rapid remissions in a proportion of cases.

PATIENTS AND METHODS

Nineteen patients underwent infliximab therapy 5 mg/kg perioperatively to scheduled anal reconstructive surgery for complicated fistulising anal Crohn's disease.

RESULTS

One adverse event was recorded (generalised exanthema with subsequent resolution). Eight patients showed complete clinical remission refusing further surgery. One of the eight relapsed during follow-up and was continued on infliximab. Surgery consisted of advancement flaps. It was successful at first attempt in nine of the remaining 11 patients (82%). Operative fistula closure remained unsuccessful in two patients. Overall, 16 of 19 patients (84%) with advanced anal Crohn's disease had a favourable outcome.

CONCLUSION

The use of infliximab as adjuvant to surgery in this series of patients with complicated anal Crohn's disease was safe. Although the data is uncontrolled a positive effect of infliximab on the outcome of surgery may be postulated since our results compare favourably with other studies.

Experimental and theoretical study of the neutron dose produced by carbon ion therapy beams

High-energy (12)C ions offer favourable conditions for the treatment of deep-seated local tumours. Several facilities for the heavy ion therapy are planned or under construction, for example the new clinical ion-therapy unit HIT at the Radiological University Clinics in Heidelberg. In order to improve existing treatment planning models, it is essential to evaluate the secondary fragment production and to include these contributions to the therapy dose with higher accuracy. Secondary neutrons are most abundantly produced in the reactions between (12)C beams and tissues. The dose contribution to tissues by a neutron is fairly small compared with the projectile and the other charged fragments due to no ionisation and the small reaction cross-sections; however, it distributes in a considerably wider region beyond the bragg-peak because of the strong penetrability. Systematic data on energy spectra and doses of secondary neutrons produced by (12)C beams using water targets of different thicknesses for various detection angles have therefore been measured in this study at GSI Darmstadt.

A new model for the determination of fluid status and body composition from bioimpedance measurements

In patients with end stage renal failure, control of the fluid status of the body is lost and fluid accumulates continuously. By dialysis therapy, excess fluid can be removed, but there are no reliable methods to establish the amount of excess fluid to be removed. Severe and even lethal complications may be the consequence of longer term deviations from a normal fluid status in dialysis patients, but also in other patient groups. Therefore, a large medical need exists for a precise and pragmatic method to determine fluid status. Bioimpedance measurement, today mainly used for nutrition status assessment, is regarded as an interesting candidate method for fluid status determination. This paper presents a four-compartment model of the human body, developed to derive information on fluid status from extra- and intracellular volumes measured by bioimpedance spectroscopy. The model allows us to determine weights of each of four compartments (overhydration, fat, muscle and remaining 'basic' components) by analyzing extra- and intracellular water volumes in different tissues of the body. Thereby fluid status (overhydration volume, normohydrated weight of the patient) as well as nutrition and fitness status (lean body, fat and muscle mass) can be determined quantitatively from a single measurement. A preliminary evaluation of the performance of a system consisting of a bioimpedance spectrum analyzer and the four-compartment model is also provided.

Detection limit of methods to assess fluid status changes in dialysis patients

Technical systems for an accurate and practicable fluid management of dialysis patients are urgently needed, since current clinical methods are partially subjective, imprecise, and time consuming. Such new systems should not only allow the determination of the target normohydration weight, but also must be able to detect clinically relevant changes in fluid volume ( approximately 1 l). This study focuses on the systematic analysis of the detection limit of several candidate methods for fluid management. In a cohort of 16 new dialysis patients, several candidate methods were applied in parallel during each treatment of the initial weight reduction phase: the measurement of vena cava diameter (VCD), vena cava collapsibility index (CI), the blood volume drop during an ultrafiltration (UF) bolus (Deltarelative blood volume (RBV)-), the rebound after the UF bolus (DeltaRBV+), and the extracellular fluid volume determined with whole body bioimpedance spectroscopy (BIS). A clinical reference method was used to manage the fluid status of patients. All methods showed significant correlations with predialysis weight. The detection limits W(lim) of candidate methods for changes in fluid status were assessed as W(lim)=0.87 kg+/-0.64 kg (BIS), 1.74 kg+/-1.56 kg (VCD), 2.3 kg+/-1.0 kg (DeltaRBV-), 7.4 kg+/-8.5 kg (CI), 40 kg+/-108 kg (DeltaRBV+). Only BIS shows a satisfactorily low detection limit W(lim), whereas W(lim) was rated as critical for the VCD and DeltaRBV- methods, and as unacceptable for the CI and DeltaRBV+ methods. Bioimpedance spectroscopy appears to be the most promising method for a practical fluid management system in dialysis.