Are changes in nociceptive withdrawal reflex magnitude a viable central sensitization proxy? Implications of a replication attempt

OBJECTIVE

The nociceptive withdrawal reflex (NWR) has been proposed to read-out central sensitization (CS). Replicating a published study, it was assessed if the NWR magnitude reflects sensitization by painful heat. Additionally, NWR response rates were compared for two stimulation, the sural nerve at the lateral malleolus (SU) and the medial plantar nerve on the foot sole (MP), and three recording sites, biceps femoris (BF), rectus femoris (RF), and tibialis anterior (TA) muscles.

METHODS

16 subjects underwent one experiment with six blocks of eight transcutaneous electrical stimulations to elicit the NWR while surface electromyography was collected. Tonic heat was concurrently applied in the same dermatome. Temperatures rose from 32 °C in the first to 46 °C in the last block following the previously published protocol.

RESULTS

Tonic heat did not influence NWR magnitude. The highest NWR response rate was obtained for MP-TA combination (79%). Regarding elicitation in all three muscles, SU stimulation outperformed MP (59% vs 57%).

CONCLUSIONS

The replication failed. NWR magnitude as a CS proxy in healthy subjects needs continued investigation. With respect to response rates, MP-TA proved efficient, whereas SU stimulation seemed preferable for multiple muscle recordings.

SIGNIFICANCE

Unclear methodological descriptions in the original study affected CS and NWR replication. The NWR magnitude changes induced by CS may closely depend on the different stimulation methods used.

Elevated risk of depression and anxiety disorder by „high strain“ occupations: a systematic review

Background

Poor working conditions might lead to mental illness.

Methods

We performed a systematic review with meta-analyses as an update of a review published in 2013. We registered the study protocol with PROSPERO (registration number: CRD42020170032) and searched for epidemiological studies in MEDLINE, PsycINFO, and Embase. Two reviewers carried out independently all review steps including title-abstract screening, full-text screening, risk-of-bias assessment and data extraction. Discordances were solved by consensus. We determined the certainty of evidence using the GRADE-approach.

Results

Ten cohort studies with acceptable study quality examined the relationship between high job strain and the incidence of depression. In the “classic” demand-control-model, ‘high strain’ (combination of high demands and low control) is compared with ‘low strain’ (combination of low demands and high job control). For high strain, the risk of depression was elevated by 73%, the pooled effect estimate for the risk of depression was 1.73 (95% CI 1.32-2.27. In a dichotomous analysis (without dividing job strain into the four dimensions mentioned above), there was a doubled risk of depression with high job strain (pooled effect estimate=1.99, 95% CI 1.68-2.35). We found comparable risk estimates for men and women. The GRADE assessment revealed a high certainty of evidence of the association between job strain and depression. We also found a considerably increased risk of anxiety disorder among individuals prone to high job strain.

Conclusions

This systematic review finds a clear association between high job strain (high demands in combination with low control) and depression as well as anxiety disorders.

Acknowledgment: This study was financially supported by SUVA (Schweizerische Unfallversicherungsanstalt).

Key messages

Active impedance matching of a cryogenic radio frequency resonator for ion traps

A combination of direct current (DC) fields and high amplitude radio frequency (RF) fields is necessary to trap ions in a Paul trap. Such high electric RF fields are usually reached with the help of a resonator in close proximity to the ion trap. Ion trap based quantum computers profit from good vacuum conditions and low heating rates that cryogenic environments provide. However, an impedance matching network between the resonator and its RF source is necessary, as an unmatched resonator would require higher input power due to power reflection. The reflected power would not contribute to the RF trapping potential, and the losses in the cable induce additional heat into the system. The electrical properties of the matching network components change during cooling, and a cryogenic setup usually prohibits physical access to integrated components while the experiment is running. This circumstance leads to either several cooling cycles to improve the matching at cryogenic temperatures or the operation of poorly matched resonators. In this work, we demonstrate an RF resonator that is actively matched to the wave impedance of coaxial cables and the signal source. The active part of the matching circuit consists of a varactor diode array. Its capacitance depends on the DC voltage applied from outside the cryostat. We present measurements of the power reflection, the Q-factor, and higher harmonic signals resulting from the nonlinearity of the varactor diodes. The RF resonator is tested in a cryostat at room temperature and cryogenic temperatures, down to 4.3 K. A superior impedance matching for different ion traps can be achieved with this type of resonator.

O-248 Cluster Analysis of men with idiopathic and unexplained male infertility identifies FSHB Genotype as relevant diagnostic parameter

Study question

In a cohort of idiopathic and unexplained infertile men we aimed to identify subgroups with similar characteristics, and therewith underlying etiologic factors, by clustering approach.

Summary answer

We identified two distinct patient clusters. Across all diverse phenotypes of infertility, the strongest segregation markers were FSHB c.-211G>T, FSH, and bi-testicular volume.

What is known already

In about 30-75% of infertile men no major causative factors can be identified; leading to the diagnose of unexplained (normozoospermia) or idiopathic (abnormal semen parameters) male infertility. This cohort of men remains very heterogenous, albeit the detailed andrological characterization that is currently applied in infertility workup.

New analysis tools such as machine learning and cluster analysis can provide a more in-depth approach. Such explorative analyses have the potential to uncover hitherto hidden patterns in data that might be difficult to spot for andrologists but become visible by these tools.

Study design, size, duration

A Cluster analysis was retrospectively performed in a clinically well characterized cohort of 2742 men with unexplained or idiopathic male infertility. These men had visited our Centre within a 10-year period (2008-2018) for infertility workup. Due to the well curated database (Androbase®) we were able to include up to 37 andrologic parameters in the unbiased cluster analysis.

Participants/materials, setting, methods

After applying strict selection criteria 2742, of initially 7627, infertile men remained for cluster analysis (exclusion: obstructive -, genetic -, other causative factors, female factor; inclusion: azoo- to normozoospermia, FSH ≥ 1IU/l, Testosterone ≥ 8nmol/l). For subsequent analyses the following parameters were included: somatic/semen/hormone parameters, testicular sonography and testis volume, genotyping of the FSHB c.-211G>T (rs10835638) single nucleotide polymorphism. For cluster analysis, partitioning around medoids method was employed based on Gower distance between patients.

Main results and the role of chance

The applied cluster approach for the study population yielded two separate clusters (average silhouette width ∼0.12). These clusters showed significantly different distributions in bi-testicular volume, FSH and FSHB genotype. Cluster 1 contained all men homozygous for G (wildtype) in FSHB c.-211G>T (100%), while Cluster 2 contained most patients carrying a T allele (>96.6%). Even in subgroup analysis (Total sperm count (TSC) <1Mill and TSC 1³Mill) two clusters each were formed too. Again, the strongest segregation markers between the respective clusters were FSHB c.-211G>T, bitesticular volume, and FSH, supporting the notion of a contributing genetic factor.

Surprisingly, sperm parameters like TSC, motility and morphology played a minor role in cluster formation; as well as testicular maldescent, varicocele, smoking, and microlithiasis testes.

The genetic parameter of FSHB c.-211G>T in combination with the established parameters FSH and testicular volume should attract more attention in future clinical workups of infertile men with unknown etiologic factors.

Limitations, reasons for caution

Categorical and numeric features contribute diversely to the calculation of patient dissimilarity. Potentially, categorical features can have a higher impact because patients are rated as completely different if they fall in different categories; for numeric features, the dissimilarity depends on the range of values.

Wider implications of the findings

The FSHB SNP was identified as an informative segregation marker; we therefore suggest introducing diagnostic genotyping into clinical routine in men with so far idiopathic or unexplained male infertility. This may reduce the high number of infertile men with so far unknown origin by nearly one-third.

Trial registration number

DFG Clinical Research Unit 326 Male Germ Cells

Changes in cardiometabolic risk factors during inpatient rehabilitation of traumatic spinal cord injury from a multicenter Swiss Spinal Cord Injury Cohort (SwiSCI)

Introduction

Cardiometabolic health has a growing relevance in spinal cord injury (SCI) considering the increasing survival and aging population. We explored longitudinal changes in cardiometabolic risk profile and examined whether injury characteristics could be a non-modifiable risk factor for individuals with SCI in subacute phase of the injury.

Methods

We used the data from a multicenter Swiss Spinal Cord Injury Cohort (SwiSCI) study and included adults with traumatic SCI (TSCI) without cardiometabolic diseases and diabetes at baseline. We included individuals with available data on admission and prior to discharge from first SCI rehabilitation. Blood pressure, lipid profile, fasting glucose, waist circumference (WC), weight, and body mass index (BMI) were compared according to the injury level (tetraplegia-TP vs paraplegia-PP) and completeness (motor complete-COM vs incomplete-INC). We used multivariable linear regression for cross-sectional analysis and linear mixed models for longitudinal analysis, adjusting for age, sex, lifestyle factors, medication-use, and injury characteristics. We performed age- (above and below median age) and sex-stratified analyses. Sensitivity analyses were also performed by removing systemic steroid-use (proxy for acute injury), adjusting for opioid-use (medication side-effect) and adjusting further for BMI and WC.

Results

We analyzed 258 individuals with TSCI (110 TP and 148 PP, 122 COM and 136 INC). Median age was 50 years (IQR 32–60), with 76.36% (n=197) of the population being male. The median rehabilitation duration was 5.5 months (IQR 3.2–7.1). On admission, the fully-adjusted models showed higher baseline weight, systolic BP, diastolic BP and triglycerides in PP than TP. Systolic BP, diastolic BP, HDL, HDL/LDL were higher in INC than COM. In the overall population, we observed increases in cholesterol, HDL, and HDL/LDL ratio over rehabilitation period. Individuals with PP had a higher increase in BMI as compared to TT, while no differences were detected when comparing INC and COM injury (Table 1–3). Results from sensitivity analyses were generally in line with the overall findings; however, at baseline, there was some indication that lipid profile may be different in COM and INC injury. In sex-stratified longitudinal analysis, triglycerides were higher in females PP than TP, and diastolic BP was higher in females with INC than COM. For age-stratified longitudinal analysis, elderly with PP have higher triglycerides than younger adults.

Conclusion

We reported changes in BMI and lipid profile during the inpatient rehabilitation of individuals with traumatic SCI and without history of cardiovascular diseases and diabetes. Injury characteristics may not be an independent risk factor for subacute phase, but maybe important in specific subgroups, like in women and in the elderly (>50 years old).

Funding Acknowledgement

Type of funding sources: None. MethodsResults

Atmospheric washout of 35S during single rain events - Implications for 35S sampling schemes

Cosmogenic radiosulfur (³⁵S; half-life: 87.4 days) is transferred with the rain to the groundwater (as ³⁵SO₄^2-) and can be used as residence time tracer for the detection of sub-yearly groundwater residence times. Due to the distinct but non-regular annual ³⁵S pattern in precipitation, related data evaluation requires consideration of a³⁵S input function that is based on representative rain samples. While minor rain events can easily be sampled quantitatively and hence representatively, a long-lasting rain event may get documented by a sample that represents only a certain sequence of the event, thus potentially resulting in a³⁵S activity concentration that might not be representative. With the aim to examine the magnitude of temporal variations of the ³⁵S activity concentration in rain during long-lasting rain events, we present and discuss two related exemplary ³⁵S time series. Furthermore, we evaluate the applicability of the parameters total sulfate and electrical conductivity (EC), both detected in rainwater as easily attainable ³⁵S proxies. The results of the study show (i) that the ³⁵S activity concentration may vary substantially during long-lasting rain events due to atmospheric migration processes and aerosol washout and (ii) that neither sulfate nor EC are suitable as ³⁵S proxies due to the different origin of ³⁵S on the one hand and sulfate/EC on the other. Hence, for the determination of a³⁵S activity concentration that is representative for a long-lasting rain event ³⁵S analyses of an adequate number of sub-samples cannot be avoided.

P13.01 Neuronal activity drives distinct invasion modes of glioma cells

BACKGROUND

Gliomas are incurable brain tumors characterized by their infiltrative growth which makes them a whole-brain disease. Previously we described membrane protrusions called tumor microtubes (TMs), and glutamatergic synapses between neurons and glioma cells, as mechanisms contributing to glioma cell invasion and tumor progression. However, the interrelation of the two, and the exact mechanisms of glioma cell dynamics over time was unknown. Therefore, we investigate neuronal synaptic input on TM-associated glioma cell motility.

MATERIAL AND METHODS

Here we established a novel workflow for analyzing single glioma cell dynamics over several hours with in-vivo two-photon microscopy. First, a membranous fluorescent marking of patient-derived glioma cells was established to reliably track membrane changes. Secondly, augmented microscopy based on deep- and machine-learning algorithms was used to track glioma cells. Neuronal activity was manipulated with different doses of isoflurane anesthesia, and used to study its effects on glioma cell dynamics.

RESULTS

This novel method revealed that motility of glioma cells can be described by the displacement of whole glioma cell somata (somatokinesis) and TM dynamics. TM motility in turn could be sub-categorized into protrusion, retraction and branching. Next, we describe three different invasion modes, all with similarities to different cell types involved in CNS development. Lastly, the effects of neuronal activity on glioma cell invasion were investigated. With the application of high anesthesia and subsequently reduced neuronal activity, TM turnover, branching events and as a result glioma cell invasion were inhibited, but in a heterogeneous manner.

CONCLUSION

The novel workflow allowed to comprehensively characterize glioma cell invasion over several hours. Its application demonstrates novel, hitherto unknown cellular mechanisms of glioma cell invasion, and provides a link between TM biology and neuron-glioma communication. Finally, neuronal input drives distinct subtypes of glioma cell motility patterns.All in all, this work presents an important first step in understanding mechanisms that lead to the whole- brain colonization of glioma cells making these brain tumors incurable. A further characterization of the exact molecular mechanisms that drive neuronal activity-dependent glioma cell motility is warranted.

O-089 A Genome Wide Association Study in men with unexplained infertility identifies nine SNPs at the FSHB locus to be associated with Follicle Stimulating Hormone level

Study question

Which single nucleotide polymorphisms (SNPs) are associated with Follicle stimulating hormone (FSH) levels in men with unexplained infertility and can affect FSH action and spermatogenesis?

Summary answer

We identified a genomic region at chromosome 11p.14.1, including nine SNPs, that are significantly associated with FSH levels in men with unexplained infertility.

What is known already

FSH action is essential for the initiation and maintenance of human spermatogenesis. One well-studied SNP, FSHB c.-211G>T (rs10835638), is associated with FSHB mRNA transcription and directly affects FSH serum levels, testicular volume and spermatogenesis. Carriers of a T-allele in this promoter are diagnosed with functional secondary hypogonadism with isolated FSH deficiency.

Other genetic variants, for example at the FSHR have been shown to slightly modulate FSH action, however the clinical impact in these variants seems to

be low. The so far identified FSH-associated SNPs revealed an impact of up to 2.3 % on FSH serum level variance.

Study design, size, duration

A Genome wide association study (GWAS) was performed on a clinically well characterized cohort of 742 men with unexplained infertility (discovery study). Of the nine identified SNPs, validation was performed for rs11031005 and the already described rs10835638 in an independent cohort of 1123 men with unexplained infertility (validation study).

Participants/materials, setting, methods

Patients were retrospectively selected from our CeRA database Androbase® applying strict selection criteria; DNA was isolated from stored EDTA-blood samples. Informative genetic variants were identified using Illumina PsychArray v1.3. Illumina®GenomeStudio v2.0, PLINK v1.90 and R 3.6.3 were used to perform quantitative association analysis based on normalized FSH values. The validation study was performed using TaqMan PCR for SNP detection and R 3.6.3 for quantitative association to analyze the impact of each SNP on FSH level.

Main results and the role of chance

Imputation of the GWAS data revealed 94 SNPs with suggestive significance (p < 8.56e-06) and nine SNPs (including rs10835638) with genome-wide significance (p < 4.28e-07). The nine SNPs are all located at the FSHB locus on Chromosome 11p.14.1 and are in high linkage disequilibrium (LD). The validation study of 1123 patients with unexplained infertility for the SNPs rs11003005 and rs10835638 revealed a significant association with FSH (p = 4.71e-06 and p = 5.55e-07) and FSH/LH ratio (p = 2.08e-12 and p = 6.4e-12).The nine significant SNPs accounted for 3.60 –4.65 % variance in FSH serum level each in the entire discovery cohort. In an oligozoospermic subgroup (n = 249) this effect was increased to 4.89 – 6.95 %.

This the first GWAS in men with unexplained infertility. This study shows that not one single SNP, but rather a genomic region has an impact on FSH serum level in men with unexplained male infertility. This effect is even more pronounced in the more severe phenotype of oligozoospermic men.

Limitations, reasons for caution

The study is restricted to men with unexplained infertility, which might cause a selection bias. Validation and functional evaluation of the eight newly identified SNPs in independent cohorts would emphasize the results more. The sample size of 742 limits detection of loci with smaller effect on FSH levels.

Wider implications of the findings

The determination of one of the nine SNPs can improve diagnostic precision in identifying men with secondary functional hypogonadism with isolated FSH deficiency. An oligozoospermic subgroup of these men would putatively benefit from FSH treatment and has to be proven in randomized controlled trials.

Trial registration number

German Research Foundation CRU326

The Restless Spinal Cord in Degenerative Cervical Myelopathy

BACKGROUND AND PURPOSE

The spinal cord is subject to a periodic, cardiac-related movement, which is increased at the level of a cervical stenosis. Increased oscillations may exert mechanical stress on spinal cord tissue causing intramedullary damage. Motion analysis thus holds promise as a biomarker related to disease progression in degenerative cervical myelopathy. Our aim was characterization of the cervical spinal cord motion in patients with degenerative cervical myelopathy.

MATERIALS AND METHODS

Phase-contrast MR imaging data were analyzed in 55 patients (37 men; mean age, 56.2 [SD,12.0] years; 36 multisegmental stenoses) and 18 controls (9 men, P = .368; mean age, 62.2 [SD, 6.5] years; P = .024). Parameters of interest included the displacement and motion pattern. Motion data were pooled on the segmental level for comparison between groups.

RESULTS

In patients, mean craniocaudal oscillations were increased manifold at any level of a cervical stenosis (eg, C5 displacement: controls [n = 18], 0.54 [SD, 0.16] mm; patients [n = 29], monosegmental stenosis [n = 10], 1.86 [SD, 0.92] mm; P < .001) and even in segments remote from the level of the stenosis (eg, C2 displacement: controls [n = 18], 0.36 [SD, 0.09] mm; patients [n = 52]; stenosis: C3, n = 21; C4, n = 11; C5, n = 18; C6, n = 2; 0.85 [SD, 0.46] mm; P < .001). Motion at C2 differed with the distance to the next stenotic segment and the number of stenotic segments. The motion pattern in most patients showed continuous spinal cord motion throughout the cardiac cycle.

CONCLUSIONS

Patients with degenerative cervical myelopathy show altered spinal cord motion with increased and ongoing oscillations at and also beyond the focal level of stenosis. Phase-contrast MR imaging has promise as a biomarker to reveal mechanical stress to the cord and may be applicable to predict disease progression and the impact of surgical interventions.

Low-sulphate water sample preparation for LSC detection of 35S avoiding sulphate precipitation

Information about groundwater residence times is essential for evaluating appropriate groundwater abstraction rates and aquifer vulnerabilities and hence for sustainable groundwater management in general. Naturally occurring radionuclides are suitable tools for related investigations. While the applicability of several long-lived radionuclides for the investigation of long-term processes has been demonstrated frequently, residence times of less than one year are only scarcely discussed in the literature. That is due to the rather small number of applicable radionuclides that show adequately short half-lives. A promising approach for investigating sub-yearly residence times applies radioactive sulphur. ³⁵S is continuously produced in the upper atmosphere from where it is transferred with the rain to the groundwater. As soon as the water enters the subsurface its ³⁵S activity concentration decreases with an 87.4 day half-life. This makes ³⁵S suitable for investigating sub-yearly groundwater residence times. However, the low ³⁵S activities in natural waters require sulphate pre-concentration for ³⁵S detection by means of liquid scintillation counting (LSC). That is usually done by sulphate extraction from large water samples with an anion-exchange resin (Amberlite IRA400, Cl-form), elution from the resin with NaCl, and precipitation as BaSO₄. Our study aimed at optimizing the standard sample preparation procedure by avoiding the laborious precipitation step. We suggest (i) sulphate extraction using the exchange resin Amberlite IRA67 (OH-form), (ii) elution with ammonium hydroxide, (iii) evaporation of the eluate and (iv) dissolving the resulting dry precipitate in 2 ml H₂O. In contrast to the standard approach our method results in a final sample solution of low ionic strength, which allows applying the water miscible scintillation cocktail Hionic-Fluor®. Since Hionic-Fluor accepts only aqueous solutions of low ionic strength the approach is applicable for waters with high ³⁵S/³²SO₄^2- ratios, i.e., low total sulphate sample loads (e.g. rainwater).

Improved approach for LSC detection of 35S aiming at its application as tracer for short groundwater residence times

The knowledge of groundwater residence times in (vulnerable) aquifers is essential for the sustainable management of the associated groundwater resources. A powerful tool for related investigations is the application of naturally occurring radioisotopes as water age indicators. However, due to the limited number of suitable (i.e. omnipresent, short-lived and easily detectable) radionuclides only few studies focus on groundwater ages below one year. A natural radionuclide that does have the potential to cover this time range is ³⁵S (87.4 day half-life). ³⁵S is continually produced in the upper atmosphere and transferred with the rain to the groundwater. Since no natural sources of ³⁵S exist in the subsurface the decrease of the ³⁵S activity concentration in such young groundwater can be used for the determination of its age. Still, ³⁵S activities in precipitation (and hence even more in groundwater) are very low and necessitate appropriate analytical protocols based on liquid scintillation counting (LSC). This turns out to be challenging due to the required large sample volumes and due to potentially high SO₄^2- loads of the samples, both limiting the range of possible applications of ³⁵S as indicator for short groundwater residence times. In the paper we present an improved straightforward LSC based approach for the detection of ³⁵S in natural water samples. We recommend using Insta-Gel Plus as scintillation cocktail for allowing a homogeneous suspension of ³⁵S-containing BaSO₄ in the cocktail. The recommended improvements in instrument setting concern the LSC (TriCarb 3170 Tr/SL) counting window, the pulse decay discriminator setting and the delay before burst setting. The settings allow measuring low activity concentrations of ³⁵S, which was previously pre-concentrated from natural water samples, containing SO₄^2- loads of up to 1500 mg with a reasonably high statistical reliability.

All-cause and cause-specific mortality following non-traumatic spinal cord injury: evidence from a population-based cohort study in Switzerland

Study design

Observational cohort study.

Objective

To benchmark all-cause and cause-specific mortality following NTSCI to the general population (GP).

Setting

Specialized rehabilitation centers in Switzerland.

Methods

Longitudinal data from the Swiss Spinal Cord Injury (SwiSCI) Medical Record study were probabilistically linked with cause of death (CoD) information from the Swiss National Cohort. Standardized mortality ratios (SMRs) were estimated for all-cause and cause-specific mortality. Competing risk frameworks were used to estimate the probability of death due to specific CoD.

Results

One thousand five hundred and one individuals were admitted for first rehabilitation with NTSCI between 1990–2011; CoD information was available for 454 individuals of the 525 individuals that died. Overall, the mortality rate for persons with NTSCI was 1.6 times greater than that of the GP. Deaths due to cardiovascular disease (39.8%), neoplasms (22%), and infection (9.9%) were most often reported. Individuals with an SCI due to a vascular etiology indicated the greatest burden of mortality from infection compared with the GP (SMR 5.4; 95% CI, 3.1 to 9.2).

Conclusions

Cause-specific SMRs varied according to etiology. This supports the need for targeted clinical care and follow-up. Cardiovascular disease, neoplasms, and infection, emerged as main causes of death following NTSCI and should thus be targets for future research and differential clinical management approaches.

Estimation of Sparse VAR Models with Artificial Neural Networks for the Analysis of Biosignals

Vector autoregressive models (VAR models) are often used to model and to analyze multivariate time series, especially to provide short-term forecasts. A common method of estimating coefficients of these VAR models is solving the Yule- Walker equations. This work introduces and investigates a method to set up "sparse" VAR models, in order to obtain a comparable prognosis quality with significantly fewer coefficients. For this purpose, an artificial neural network was programmed in Python with TensorFlow. Sparsity arises from the implementation of regularization algorithms.Based on simulated data and an ECG, we show that a comparable prognosis quality can be achieved with significantly fewer coefficients. In addition, sparse VAR models can also be determined if the data would actually lead to an underdetermined system of equations. Thus, sparse VAR models may help to classify short epochs of biosignals, e.g. P-waves or QRS-complexes.

Diagnostic accuracy of a new ex vivo confocal laser scanning microscope compared to H&E-stained paraffin slides for micrographic surgery of basal cell carcinoma

BACKGROUND

For safe excision of malignant skin tumours, complete negative surgical margins are mandatory. The gold standard for analysis is frozen sections or paraffin-embedded haematoxylin and eosin (H&E)-stained slides. The production of H&E-stained slides is time-consuming (>20 h) while wounds remain unclosed. An upcoming method is confocal laser scanning microscopy (CLSM), a technique that scans unfixed fresh tissue rapidly.

OBJECTIVE

Evaluation of the process to generate and analyse CLSM images and assessment of the accuracy to detect basal cell carcinoma (BCC) tissue.

METHODS

Digital microscopic images were generated by the Histolog Scanner v1 from 544 fresh specimens of 148 BCCs that had been stained with a 0.01% proflavine solution. CLSM images were compared to the histological diagnoses of the corresponding H&E-stained slides.

RESULTS

A total of 525 images could be analysed. The sensitivity was 73% (95% CI = [65.27%; 80.47%]), and the specificity was 96% (95% CI = [93.40%; 97.60%]). Detection of BCCs in punch biopsies was certainly detected (sensitivity of 100%). The median total time to generate and evaluate a CLSM image was 5.17 min (maximum 20.17 min and minimum 2.05 min). The greatest challenge was flattening the specimen to assure complete representation of the surgical margins.

CONCLUSION

Confocal laser scanning microscopy is a time-saving and very effective alternative to classical paraffin-embedded or frozen sections. Patient treatment could be improved due to shorter hospital stays or faster outpatient therapy due to reduced intervals between surgical stages. Diagnostic accuracy of the microscope used still must be improved.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Paraneoplastic cerebellar degeneration: Yo antibody alters mitochondrial calcium buffering capacity

Aim

Neurodegeneration is associated with dysfunction of calcium buffering capacity and thereby sustained cellular and mitochondrial calcium overload. Paraneoplastic cerebellar degeneration (PCD), characterized by progressive Purkinje neurone degeneration following paraneoplastic Yo antibody internalization and binding to cerebellar degeneration‐related protein CDR2 and CDR2L, has been linked to intracellular calcium homeostasis imbalance due to calbindin D_28k malfunction. Therefore, we hypothesized that Yo antibody internalization affects not only calbindin calcium binding capacity, but also calcium‐sensitive mitochondrial‐associated signalling, causing mitochondrial calcium overload and thereby Purkinje neurone death.

Methods

Immunohistochemically, we evaluated cerebellar organotypic slice cultures of rat brains after inducing PCD through the application of Yo antibody‐positive PCD patient sera or purified antibodies against CDR2 and CDR2L how pharmacologically biased mitochondrial signalling affected PCD pathology.

Results

We found that Yo antibody internalization into Purkinje neurons caused depletion of Purkinje neurone calbindin‐immunoreactivity, cannabinoid 1 receptor over‐activation and alterations in the actions of the mitochondria permeability transition pore (MPTP), voltage‐dependent anion channels, reactive oxygen species (ROS) and Na⁺/Ca²⁺ exchangers (NCX). The pathological mechanisms caused by Yo antibody binding to CDR2 or CDR2L differed between the two targets. Yo‐CDR2 binding did not alter the mitochondrial calcium retention capacity, cyclophilin D‐independent opening of MPTP or activity of NCX.

Conclusion

These findings suggest that minimizing intracellular calcium overload toxicity either directly with cyclosporin‐A or indirectly with cannabidiol or the ROS scavenger butylated hydroxytoluene promotes mitochondrial calcium homeostasis and may therefore be used as future neuroprotective therapy for PCD patients.

Errata: Die Zukunft der medizinisch–rehabilitativen Versorgung im Kontext der Multimorbidität – Teil I: Begriffsbestimmung, Versorgungsfragen und Herausforderungen

W. Seger, W. Cibis, A. Deventer, S. Grotkamp, N. Lübke, P.-W. Schönle, M. Schubert. Die Zukunft der medizinisch-rehabilitativen Versorgung im Kontext der Multimorbidität – Teil I: Begriffsbestimmung, Versorgungsfragen und Herausforderungen Künstlerische Therapeuten im Gesundheitswesen. Gesundheitswesen 2016;

Bei diesem Beitrag fehlte ein Autor und die zugehörige Institutsangabe. Nachfolgend die ergänzten Autoren und Institute:

Autoren: W. Seger1, W. Cibis2, A. Deventer3, S. Grotkamp4, N. Lübke5, P.-W. Schönle6, M. Schmidt-Ohlemann7, M. Schubert2

Institute: 1 MDK Niedersachsen, Hannover 2 Bundesarbeitsgemeinschaft für Rehabilitation (BAR), Frankfurt 3 Praxis für Physikalische und Rehabilitative Medizin, Hamburg 4 MDK Niedersachsen, SEG 1, Hannover 5 Kompetenz-Centrum Geriatrie (KCG), Hamburg 6 Maternus Kliniken, Bad Oeynhausen 7 Diakonie Bad Kreuznach, Rehabilitationsklinik, Bad Kreuznach

Interface Adhesion and Structural Characterization of Rolled-up GaAs/In0.2Ga0.8As Multilayer Tubes by Coherent Phonon Spectroscopy

We present a detailed experimental and theoretical study of the acoustic phonon modes in rolled-up multilayers with thickness of the layers in the nanometre and diameters in the micrometre range. We compare our results to planar, unrolled multilayers grown by molecular beam epitaxy. For the planar multilayers the experimentally obtained acoustic modes exhibit properties of a superlattice and match well to calculations obtained by the Rytov model. The rolled-up superlattice tubes show intriguing differences compared to the planar structures which can be attributed to the imperfect adhesion between individual tube windings. A transfer matrix method including a massless spring accounting for the imperfect adhesion between the layers yields good agreement between experiment and calculations for up to five windings. Areas with sufficient mechanical coupling between all windings can be distinguished by their acoustic mode spectrum from areas where individual windings are only partially in contact. This allows the spatially resolved characterization of individual tubes with micrometre spatial resolution where areas with varying interface adhesion can be identified.

Anisotropic contrast optical microscope

An optical microscope is described that reveals contrast in the Mueller matrix images of a thin, transparent, or semi-transparent specimen located within an anisotropic object plane (anisotropic filter). The specimen changes the anisotropy of the filter and thereby produces contrast within the Mueller matrix images. Here we use an anisotropic filter composed of a semi-transparent, nanostructured thin film with sub-wavelength thickness placed within the object plane. The sample is illuminated as in common optical microscopy but the light is modulated in its polarization using combinations of linear polarizers and phase plate (compensator) to control and analyze the state of polarization. Direct generalized ellipsometry data analysis approaches permit extraction of fundamental Mueller matrix object plane images dispensing with the need of Fourier expansion methods. Generalized ellipsometry model approaches are used for quantitative image analyses. These images are obtained from sets of multiple images obtained under various polarizer, analyzer, and compensator settings. Up to 16 independent Mueller matrix images can be obtained, while our current setup is limited to 11 images normalized by the unpolarized intensity. We demonstrate the anisotropic contrast optical microscope by measuring lithographically defined micro-patterned anisotropic filters, and we quantify the adsorption of an organic self-assembled monolayer film onto the anisotropic filter. Comparison with an isotropic glass slide demonstrates the image enhancement obtained by our method over microscopy without the use of an anisotropic filter. In our current instrument, we estimate the limit of detection for organic volumetric mass within the object plane of ≈49 fg within ≈7 × 7 μm² object surface area. Compared to a quartz crystal microbalance with dissipation instrumentation, where contemporary limits require a total load of ≈500 pg for detection, the instrumentation demonstrated here improves sensitivity to a total mass required for detection by 4 orders of magnitude. We detail the design and operation principles of the anisotropic contrast optical microscope, and we present further applications to the detection of nanoparticles, to novel approaches for imaging chromatography and to new contrast modalities for observations on living cells.

Die Zukunft der medizinisch-rehabilitativen Versorgung im Kontext der Multimorbidität – Teil II: Strukturelle Voraussetzungen und Anforderungen an das rehabilitative Versorgungssystem

Hintergrund: Multimorbide Versicherte mit 2 und mehr chronischen Krankheiten mit sozialmedizinischer Relevanz, rücken immer mehr in den Vordergrund rehabilitativer Versorgung.

Methodik: Nach Klärung von Begriffen, Versorgungsfragen und Herausforderungen der Rehabilitation (Teil I) beschreibt eine Projektgruppe des Ärztlichen Sachverständigenrates der Bundesarbeitsgemeinschaft für Rehabilitation (BAR) vielfältige Handlungsfelder für die rehabilitative Versorgung von Personen mit Multimorbidität.

Ergebnisse: Der Sachverständigenrat empfiehlt ein Bündel möglicher und notwendiger Maßnahmen Diese reichen in ihrer Vielfalt von der Überprüfung des Formularwesens auf valide Identifizierung der rehabilitativen Bedarfe über eine diesbezügliche Sensibilisierung und Kompetenzerweiterung des involvierten Personals der Sozialleistungsträger und der Rehabilitationseinrichtungen bis hin zu einer Berücksichtigung von Multimorbidität in Leitlinien sowie Klärung noch offener Forschungsfragen.

Die Zukunft der medizinisch–rehabilitativen Versorgung im Kontext der Multimorbidität – Teil I: Begriffsbestimmung, Versorgungsfragen und Herausforderungen

Hintergrund: Multimorbide Personen mit 2 und mehr chronischen Krankheiten mit sozialmedizinischer Relevanz, rücken immer mehr in den Vordergrund der rehabilitativen Versorgung.

Methodik: Nach Klärung der Begriffsbestimmung von Multimorbidität im rehabilitativen Kontext und orientierender Literaturauswertung zu deren Prävalenz und Folgen wurden ausgehend von einem kasuistischen Beispiel besondere Anforderungen und allgemeine Herausforderungen für die Leistungsgestaltung sowie für die rehabilitative Versorgung herausgearbeitet und im Ärztlichen Sachverständigenrat der Bundesarbeitsgemeinschaft für Rehabilitation (BAR) konsentiert.

Ergebnis: Der Handlungsbedarf bei multimorbiden Versicherten reicht von der funktionsbezogenen, individuellen Bedarfsermittlung über die Zuweisungspraxis, Rehabilitationsdurchführung und -nachsorge bis zur Reintegration der Rehabilitanden in den Sozialraum.

[On the Differential Diagnosis of Intractable Psychogenic Chronic Cough: Neuropathic Larynx Irritable - Gabapentin's Antitussive Action]

We present the case of a 76 year old female inpatient who suffered from a chronic intractable cough which arose simultaneously to a severe major depression and was secondary to an exorbitant psychological distress. Chronic cough had never been experienced before and was initially considered to have a mere psychogenic origin since a comprehensive and guideline-based diagnostic screening did not reveal any underlying somatic cause. However, several factors cast doubt on the solitary psychic genesis of the chronic cough: i) occurrence immediately after a penetrant cold, ii) embedding in other complaints of laryngeal hyperreagibility (larynx irritable), such as persistent globus pharyngeus sensation, throat clearing and episodic dysphonia, iii) first occurrence on old life, iv) erupting from sleep as well, v) persistence despite remission of the major depression, and v) no sustaining benefit from specific psychotherapy and speech therapy. Therefore, diagnostics were extended to apparative tools for objective evaluation of swallowing by using fiberoptic videoendoscopic (FEES) and videofluoroscopic (VFS) techniques, which revealed signs of laryngeal neuropathy but without evidence of penetration or aspiration. A co-existing small goiter and an impaired glucose tolerance along with a putative intracellular vitamin B12 or folate deficiency (as indirectly derived from an apparent hyperhomocysteinemia) were assumed to be responsible for the neuropathy and underwent specific treatments. The impaired glucose tolerance and putative vitamin deficit were compatible with a distal symmetric sensorimotoric, even subclinical polyneuropathy of the lower extremities. The larynx irritable improved under gabapentin being confirmed by drug removals several times, and finally calmed down almost completely under gabapentin, which was in line with the scant literature of this topic. Re-examination of the larynx per FEES nine months later showed no deficits any more under the well-tolerated treatment (gabapentin, levothyroxine, vitamin B12 and folic acid substitution, weight reduction and physical training). All in all, the larynx irritable as well as the chronic cough were most probably induced by a laryngeal neuropathy and were not solely of psychic origin. Due to good treatment options a larynx irritable should be regularly taken into consideration of the investigation of intractable chronic cough. Therefore, an apparative evaluation of deglutition is recommended in the diagnostic toolbox of chronic cough - even if embedded in a psychiatric disorder or distress - before diagnosing a sole psychic origin. An hypothetical scheme of the development of a larynx irritable caused by neuropathic and non-neuropathic ("nociceptive") conditions is proposed.

Efficient production of Al(OH)3-immobilized laccase with a Heterobasidion annosum strain selected by microplate screening

AIMS

  Wild-type white rot fungi are the most important production organisms for laccase, a promising oxidative biocatalyst with numerous applications. This study aimed at identifying novel highly productive strains, finding optimal cultivation conditions for laccase production and establishing a simple immobilization procedure.

METHODS AND RESULTS

  By using a newly developed 96-well microplate cultivation method, 23 species of white rot fungi, represented by 29 strains, were directly compared with regard to the amount of secreted laccase. Both, with glucose and spruce saw dust as growth substrate a Heterobasidion annosum strain and a Physisporinus vitreus strain were the most productive (730–2200 U l−1 of secreted laccase). Cultivation conditions for laccase production with H. annosum were optimized in larger-scale liquid cultures. Aeration with a sparger lead to a 3·8-fold increase in laccase activity when compared to nonaerated flask cultures. More than 3000 U l−1 laccase was produced in glucose medium supplemented with yeast extract and the inducer veratryl alcohol. Culture supernatant was incubated with short-range ordered Al(OH)3 particles to directly immobilize and concentrate laccase by adsorption. Active laccase was recovered in 40% yield and the Al(OH)3-adsorbed laccase was suitable for repeated decolourization of indigo carmine.

CONCLUSIONS

  Microplate cultivation allowed a large-scale comparison of the capacity of different fungal species for laccase production. Laccase secretion of a highly productive H. annosum strain was found to vary strongly with different cultivation conditions. Adsorption to Al(OH)3 proved to be suitable as direct immobilization technique.

Collective Modes and Structural Modulation in Ni-Mn-Ga(Co) Martensite Thin Films Probed by Femtosecond Spectroscopy and Scanning Tunneling Microscopy

The origin of the martensitic transition in the magnetic shape memory alloy Ni-Mn-Ga has been widely discussed. While several studies suggest it is electronically driven, the adaptive martensite model reproduced the peculiar nonharmonic lattice modulation. We used femtosecond spectroscopy to probe the temperature and doping dependence of collective modes, and scanning tunneling microscopy revealed the corresponding static modulations. We show that the martensitic phase can be described by a complex charge-density wave tuned by magnetic ordering and strong electron-lattice coupling.