Position Statement: Linear prurigo is a subtype of chronic prurigo

BACKGROUND

Chronic prurigo (CPG) is a distinct disease characterized by chronic pruritus, history and/or signs of prolonged scratching and multiple pruriginous lesions. It may present with various clinical manifestations, including papules, nodules, plaques or umbilicated lesions. Some patients with chronic pruritus show pruriginous linear and scaring scratch lesions (LSSL) and it is unclear whether these lesions belong to the spectrum of CPG.

OBJECTIVE

To achieve a consensus on the classification of pruriginous LSSL and establish criteria to differentiate them from similar appearing conditions of different nature.

METHODS

Members of the Task Force Pruritus (TFP) of the European Academy of Dermatology and Venereology participated in the consensus conference, discussing representative clinical cases. Using the Delphi method, consensus was reached when ≥75% of members agreed on a statement.

RESULTS

Twenty-one members of the TFP with voting rights participated in the meeting. It was consented that LSSL occurs due to chronic pruritus and prolonged scratching, and share common pathophysiological mechanisms with CPG. LSSL were thus considered as belonging to the spectrum of CPG and the term 'linear prurigo' was chosen to describe this manifestation.

CONCLUSION

Considering linear prurigo as belonging to the spectrum of CPG has important clinical implications, since both the diagnostic and therapeutic approach of these patients should be performed as recommended for CPG. Importantly, linear prurigo should be differentiated from self-inflicted skin lesions as factitious disorders or skin picking syndromes. In the latter, artificial manipulation rather than pruritus itself leads to the development of cutaneous lesions, which can show clinical similarities to linear prurigo.

Relations between a standardized experimental stressor and cutaneous sensory function in patients with chronic pruritus and healthy controls: an experimental case-control study

Background

While chronic pruritus (CP) is a frequent symptom, many aspects of its underlying pathophysiological mechanisms still need elucidation. Research on sensory cutaneous function and on the influence of stress has been conducted mainly in patients with atopic dermatitis but is lacking for patients with CP.

Objective

To assess whether a standardized social stressor influences cutaneous sensory function in patients with CP in comparison with healthy controls (HC).

Methods

Case–control study; 33 CP and 30 HC were submitted to the standardized quantitative sensory testing protocol before and after the Trier Social Stress Test and 1 h later. Intraepidermal nerve fibre density (IENFD) was determined.

Results

Mechanical pain sensitivity and mechanical detection thresholds were significantly higher in CP than in HC, and mechanical detection thresholds increased more in CP than in HC over the three measurements. In both groups, cold pain threshold increased and heat pain threshold decreased from before to after the stress test and remained constant 1 h later. Only in CP, almost all QST tests induced at least a small amount of pruritus, which was not significantly altered by the stress test. IENFD in pruritic skin was significantly reduced in CP when compared to healthy controls.

Conclusion

Peripheral thermal sensory function was not altered in CP despite reduced IENFD in lesional skin, but we could demonstrate central sensitization processes specifically in CP and influences of an acute stressor inducing more sensitivity to thermal pain in both groups.

Identifying Asthma Exacerbation-Related Emergency Department Visit Using Electronic Medical Record and Claims Data

Background  Asthma exacerbation leading to emergency department (ED) visit is prevalent, an indicator of poor control of asthma, and is a potentially preventable clinical outcome.

Objective  We propose to utilize multiple data elements available in electronic medical records (EMRs) and claims database to create separate algorithms with high validity for clinical and research purposes to identify asthma exacerbation-related ED visit among the general population.

Methods  We performed a retrospective study with inclusion criteria of patients aged 4 to 40 years, a visit to Geisinger ED from January 1, 2006, to October 28, 2013, with asthma on their problem list. Different electronic data elements including chief complaints, vitals, season, smoking, medication use, and discharge diagnoses were obtained to create the algorithm. A stratified random sample was generated to select the charts for review. Chart review was performed to classify patients with asthma-related ED visit, that is, the gold standard. Two reviewers performed the chart review and validation was done on a small subset.

Results  There were 966 eligible ED visits in the EMR sample and 731 in the claims sample. Agreement between reviewers was 95.45% and kappa statistic was 0.91. Mean age of the EMR sample was 22 years, and mostly white (93%). Multiple models conventionally used in studies were evaluated and the final model chosen included principal diagnosis, bronchodilator, and steroid use for both algorithms, chief complaints for EMR, and secondary diagnosis for claims. Area under the curve was 0.93 (95% confidence interval: 0.91–0.94) and 0.94 (0.93–0.96), respectively, for EMR and claims data, with positive predictive value of > 94%. The algorithms are visually presented using nomograms.

Conclusion  We were able to develop two separate algorithms for EMR and claims to identify asthma exacerbation-related ED visit with excellent diagnostic ability and varying discrimination threshold for clinical and research purposes.

Characterization of degeneration phenomena in lithium-ion batteries by combined microscopic techniques

The application of detector strategies in scanning electron microscopy (SEM) correlated with computer tomography (CT) and light microscopy (LM) delivered unique new insights in degeneration effects of lithium-ion batteries. There we exemplary studied reference, cycled and storage cells. High-resolution SEM permit to visualize a coating on top of the cathode material of the treated cells for the first time, which also connects the conductive additives and battery active material. This confirms the assumption of a solid permeable interface on top of the cathode. The detection of low-loss reflected backscattered electrons for energies beyond 3 keV increases the available spatial resolution for material contrast. This offered the opportunity to address the atomic number of precipitates in the nm range inside the coating to be above carbon and below Li_1-x(Ni_1/3Mn_1/3Co_1/3)O₂ (NMC). Applying voltage contrast enables to show the difference in electronic conductivity of plate-like features on top of the cycled cell anode, most likely lithium plating. Cross sectional images of the anode delivered a significant change of the surficial-area morphology for the treated cells with increasing porosity. Precipitates were detected on top of the separator foil. An increment in thickness of the entire treated cells by computer tomography was found, which can be explained by the alteration of the anode, separator and cathode.

[Imaging and biopsy of soft tissue tumors]

Soft tissue tumors represent a special challenge in interdisciplinary cooperation. Malignant tumors require a multimodal therapy concept so that patient treatment in a specialized tumor center is recommended. The task of the surgeon in close cooperation with the radiologist is the resection of the tumor in sano with the required safety margin. The aim of diagnostic imaging is to describe the primary expansion of the tumor size and a possible tumor infiltration of adjacent compartments. The most important diagnostic imaging for this purpose is magnetic resonance imaging (MRI), especially T1-weighted fat-suppressed gadolinium-enhanced sequences. Together with T2-weighted sequences a reliable differentiation between necrosis and vital tumor tissue is possible, which enables a targeted biopsy of vital tumor tissue. For the differentiation between benign and malignant soft tissue tumors and for determination of histological differentation a core needle biopsy, either computer tomography-guided or under sonographic control and increasingly more by MRI guidance, is currently the gold standard in most tumor centers. A representative biopsy from vital tumor tissue leads to the diagnosis with a very high degree of certainty.

Characterisation of anticancer peptides at the single-cell level

The development of efficacious anticancer therapeutics is difficult due to the heterogeneity of the cellular response to chemotherapy. Anticancer peptides (ACPs) are promising drug candidates that have been shown to be active against a range of cancer cells. However, few ACP studies focus on tumour single-cell heterogeneities. In order to address this need, we developed a microfluidic device and an imaging procedure that enable the capture, monitoring, and analysis of several hundred single cells for the study of drug response. MCF-7 human breast adenocarcinoma cells were captured in hydrodynamic traps and isolated in individual microchambers of less than 100 pL volume. With pneumatic valves, different sets of microchambers were actuated to expose the cells to various drugs. Here, the effect of three membranolytic ACPs - melittin, aurein 1.2 and aurein 2.2 - was investigated by monitoring the efflux of calcein from single MCF-7 cells. The loss of membrane integrity was observed with two different strategies that allow either focusing on one cell for mechanistic studies or parallel analysis of hundreds of individual cells. In general, the device is applicable to the analysis of the effect of various drugs on a large number of different cell types. The platform will enable us in the future to determine the origin of heterogeneous responses on pharmacological substances like ACPs within cell populations by combining it with other on-chip analytical methods.

[Conventional radiological diagnosis of benign none neoplasms]

BACKGROUND

Benign bone tumors are of special clinical importance because they might be confused with malignant bone tumors.

OBJECTIVES

The aim of this article it to present the characteristics of benign bone tumors. The focus is orientated towards conventional x‑ray as the essential pillar for primary diagnosis. Consequently, the description of signal intensities of benign bone tumors in magnetic resonance images or less helpful clues like male-female ratios are deliberately omitted.

RESULTS

The classification of bone tumors introduced by Lodwick allows the identification of benign growth patterns. Growth patterns will not help, for example, in case of dedifferentiation of benign chondroid tumors towards chondrosarcomas. Therefore, each diagnosis has to incorporate the patient's clinical scenario. Furthermore, benign bone tumors might also cause aggressive growth patterns. Tumors classified as Lodwick Ic or higher should not be automatically regarded as malignant. Naturally, further clarification is mandatory for these tumors.

CONCLUSIONS

Differentiation between definitely benign bone tumors and those which need further work up is a critical diagnostic step. In the majority of cases, this is possible based on the appearance in conventional x‑ray images. In case of possibly malignant lesions, both the patient's symptoms and the x‑ray morphology have to be considered by orthopedic surgeons, pathologists, and radiologists to determine the optimal diagnostic strategy.

[Update in neuroanesthesiology - key publications]

One of the aims of the Scientific Working Group Neuroanesthesia (WAKNA) of the German Society of Anesthesiology and Intensive Care Medicine is to disseminate new findings in the field of neuroscience and neuroanesthesia and to propagate novel therapeutic and diagnostic options into clinical practice. Once a year, the WAKNA displays and discusses recent noteworthy publications from the past 12 months at the German Anesthesia Meeting. In 2016, a new pharmacologic strategy with dexmedetomidine to prevent postoperative pain after craniotomy, the impact of the widely used anesthetic drug propofol on GABA receptor surface expression, a study highlighting the ultrasound-guided detection of increased intracranial pressure, and an article showing the interactions of neuromuscular blocking drugs on the BIS neuromonitoring were presented.

Sixfold improved single particle measurement of the magnetic moment of the antiproton

Our current understanding of the Universe comes, among others, from particle physics and cosmology. In particle physics an almost perfect symmetry between matter and antimatter exists. On cosmological scales, however, a striking matter/antimatter imbalance is observed. This contradiction inspires comparisons of the fundamental properties of particles and antiparticles with high precision. Here we report on a measurement of the g-factor of the antiproton with a fractional precision of 0.8 parts per million at 95% confidence level. Our value /2=2.7928465(23) outperforms the previous best measurement by a factor of 6. The result is consistent with our proton g-factor measurement gp/2=2.792847350(9), and therefore agrees with the fundamental charge, parity, time (CPT) invariance of the Standard Model of particle physics. Additionally, our result improves coefficients of the standard model extension which discusses the sensitivity of experiments with respect to CPT violation by up to a factor of 20.

De-orphaning the marine natural product (±)-marinopyrrole A by computational target prediction and biochemical validation

A machine-learning method led to the discovery of the macromolecular targets of the natural anticancer compound marinopyrrol A.

Highly sensitive superconducting circuits at ∼700 kHz with tunable quality factors for image-current detection of single trapped antiprotons

We developed highly sensitive image-current detection systems based on superconducting toroidal coils and ultra-low noise amplifiers for non-destructive measurements of the axial frequencies (550-800 kHz) of single antiprotons stored in a cryogenic multi-Penning-trap system. The unloaded superconducting tuned circuits show quality factors of up to 500 000, which corresponds to a factor of 10 improvement compared to our previously used solenoidal designs. Connected to ultra-low noise amplifiers and the trap system, signal-to-noise-ratios of 30 dB at quality factors of >20 000 are achieved. In addition, we have developed a superconducting switch which allows continuous tuning of the detector's quality factor and to sensitively tune the particle-detector interaction. This allowed us to improve frequency resolution at constant averaging time, which is crucial for single antiproton spin-transition spectroscopy experiments, as well as improved measurements of the proton-to-antiproton charge-to-mass ratio.

Spotting and designing promiscuous ligands for drug discovery

The promiscuous binding behavior of bioactive compounds forms a mechanistic basis for understanding polypharmacological drug action. We present the development and prospective application of a computational tool for identifying potential promiscuous drug-like ligands. In combination with computational target prediction methods, the approach provides a working concept for rationally designing such molecular structures. We could confirm the multi-target binding of a de novo generated compound in a proof-of-concept study relying on the new method.

[Undesired awareness phenomena during general anesthesia: Evidence-based state of knowledge, current discussions and strategies for prevention and management]

Patient awareness during general anesthesia and the later recall of what happened during surgery can be experienced by patients as horrifying events that leave lasting mental trauma in the form of posttraumatic stress syndrome (PTSS). Awareness is related to a temporary insufficient depth of anesthesia. This phenomenon has been discussed for more than 20 years. According to randomized controlled studies, in the absence of risk factors awareness phenomena occur in 1-2 per 1000 operations involving general anesthesia (0.1-0.2%) and are classified as occasionally occurring critical events. An astonishing twist occurred elicited by the recent data from the 5th National Audit Project from Great Britain (NAP5) published in the British Journal of Anaesthesia and in Anaesthesia. The NAP5 evaluated patient reports of accidental awareness during general anesthesia (AAGA) in a multicenter manner in more than 2.7 million cases and indicated incidences of awareness of only 1:19,600, a frequency 20 times less than previously reported. These results gave rise to some controversy. It seems likely that, due to the absence of structured interviews, the NAP5 data only demonstrated the tip of the iceberg and may have vastly underestimated the real incidence of intraoperative awareness. The present overview summarizes the current knowledge about awareness. Furthermore, it addresses the question whether the awareness problem has been overestimated by evidence-based criteria or underestimated by the results of the NAP5. The responsibility for sufficient anesthesia in the clinical routine requires knowledge of awareness risks and potential sequelae. A formal recommendation from the German Society of Anesthesia and Intensive Care Medicine (DGAI) concerning awareness is not yet available; however, the recognition of evidence-based strategies in the management of anesthesia may minimize the occurrence of awareness and its sequelae.

Multi-objective active machine learning rapidly improves structure-activity models and reveals new protein-protein interaction inhibitors

Active machine learning puts artificial intelligence in charge of a sequential, feedback-driven discovery process. We present the application of a multi-objective active learning scheme for identifying small molecules that inhibit the protein-protein interaction between the anti-cancer target CXC chemokine receptor 4 (CXCR4) and its endogenous ligand CXCL-12 (SDF-1). Experimental design by active learning was used to retrieve informative active compounds that continuously improved the adaptive structure-activity model. The balanced character of the compound selection function rapidly delivered new molecular structures with the desired inhibitory activity and at the same time allowed us to focus on informative compounds for model adjustment. The results of our study validate active learning for prospective ligand finding by adaptive, focused screening of large compound repositories and virtual compound libraries.