A literature review and expert consensus statement on diagnostics in suspected metal implant allergy.

BACKGROUND: Although rare, allergic reactions to metal implants represent a diagnostic challenge in view of missing guidelines. OBJECTIVES: To develop an European expert consensus on characteristics of metal allergy reactions and the utility of various diagnostic tools in suspected metal implant allergy. METHODS: A nominal group technique (NGT) was applied to develop consensus statements. Initially an online literature database was created on a secure server to enable a comprehensive information. Twenty-three statements were formulated on potential aspects of metal implant allergy with a focus on diagnostics and grouped into five domains. For the consensus development, the panel of 12 experts initially did refine and reformulate those statements that were ambiguous or had unclear wording. By face-to-face (9/12) or virtual participation (3/12), an anonymous online voting was performed. RESULTS: Consensus (≥80% of agreement) was reached in 20/23 statements. The panel agreed that implant allergy despite being rare should be considered in case of persistent unexplained symptoms. It was, however, recommended to allow adequate time for resolution of symptoms associated with healing and integration of an implant. Obtaining questionnaire-aided standardized medical history and standardized scoring of patient outcomes was also considered an important step by all experts There was broad consensus regarding the utility/performance of patch testing with additional late reading. It was recognized that the lymphocyte transformation test (LTT) has to many limitations to be generally recommended. Prior to orthopaedic implant, allergy screening of patients without a history of potential allergy to implant components was not recommended. CONCLUSIONS: Using an expert consensus process, statements concerning allergy diagnostics in suspected metal implant allergy were created. Areas of nonconsensus were identified, stressing uncertainty among the experts around topics such as preoperative testing in assumed allergy, histological correlate of periimplant allergy and in vitro testing, which underscores the need for further research.

Deep learning-based classification of dermatological lesions given a limited amount of labelled data.

BACKGROUND: Artificial intelligence (AI) techniques are promising in early diagnosis of skin diseases. However, a precondition for their success is the access to large-scaled annotated data. Until now, obtaining this data has only been feasible with very high personnel and financial resources. OBJECTIVES: The aim of this study was to overcome the obstacle caused by the scarcity of labelled data. METHODS: To simulate the scenario of label shortage, we discarded a proportion of labels of the training set. The training set consisted of both labelled and unlabelled images. We then leveraged a self-supervised learning technique to pretrain the AI model on the unlabelled images. Next, we fine-tuned the pretrained model on the labelled images. RESULTS: When the images in the training dataset were fully labelled, the self-supervised pretrained model achieved 95.7% of accuracy, 91.7% of precision and 90.7% of sensitivity. When only 10% of the data were labelled, the model could still yield 87.7% of accuracy, 81.7% of precision and 68.6% of sensitivity. In addition, we also empirically verified that the AI model and dermatologists are consistent in visually inspecting the skin images. CONCLUSIONS: The experimental results demonstrate the great potential of the self-supervised learning in alleviating the scarcity of annotated data.

Risks and benefits of dermatological machine learning health care applications-an overview and ethical analysis.

BACKGROUND: Visual data are particularly amenable for machine learning techniques. With clinical photography established for skin surveillance and documentation purposes as well as progress checks, dermatology is an ideal field for the development and application of emerging machine learning health care applications (ML-HCAs). To date, several ML-HCAs have detected malignant skin lesions on par with experts or found overlooked visual patterns that correlate with certain dermatological diseases. However, it is well established that ML-HCAs come with ethical and social implications. OBJECTIVES: Currently, there is a lack of research that establishes model design, training, usage and regulation of such technologies sufficient to ensure ethically and socially responsible development and clinical translation, specifically within the field of dermatology. With this paper, we aim to give an overview of currently discussed ethical issues relating to dermatological ML-HCAs. METHODS: On the basis of a thematic, keyword-based literature search, we performed an ethical analysis against established frameworks of biomedical ethics. We combined our results with current, relevant normative machine learning ethics literature to identify the status quo of the ethics of ML-HCAs in dermatology. We describe the benefits and risks of dermatological ML-HCAs that are currently being developed for clinical purposes. RESULTS: The potential benefits range from better patient outcomes to better knowledge accessibility to decreasing health care disparities, that is, standards of care between different population groups. The risks associated with ML-HCAs range from confidentiality issues to individual patient outcomes as well as the exacerbation of prevalent health care disparities. We discuss the practical implications for all stages of dermatological ML-HCA development. CONCLUSION: We found that ML-HCAs present stakeholder-specific risks for patients, health care professionals and society, which need to be considered separately. The discipline lacks sufficient biomedical ethics research that could standardize the approach to ML-HCA model design, training, use and regulation of such technologies.

[Ex vivo confocal laser scanning microscopy for melanocytic lesions and autoimmune diseases]. / Ex-vivo konfokale Laserscanmikroskopie bei melanozytären Läsionen und Autoimmunerkrankungen.

BACKGROUND: Ex vivo confocal laser scanning microscopy (CLSM) enables bedside histology and offers the surgeon a direct intraoperative tissue examination. OBJECTIVES: To determine whether this innovative, ultra-fast diagnostic tool can be expanded beyond nonmelanoma skin cancer, particularly basal cell carcinoma, to other indications including melanocytic lesions and autoimmune diseases. MATERIALS AND METHODS: Review of literature and summary of the current knowledge and experience of the use of ex vivo CLSM in melanocytic lesions and in autoimmune diseases. RESULTS: Up to date experience of the use of ex vivo CLSM in melanocytic lesions and in autoimmune diseases is limited but promising. Current knowledge on melanocytic lesions in ex vivo CLSM and their examples together with classic ex vivo CLSM features are presented. Previous results on the use of ex vivo CLSM in autoimmune dermatoses are presented, and future application possibilities of ex vivo CLSM are discussed. CONCLUSIONS: The method is particularly suitable for the rapid examination of basal cell carcinomas during Mohs surgery but could also be used in the future for the intraoperative examination of melanocytic and autoimmune skin lesions.

Breakthrough instruments and products: Lattice Lightsheet 7-Non-invasive imaging of the subcellular dynamics of life.

Light sheet fluorescence microscopy has become an established method for fast and sensitive imaging of living specimens with minimum phototoxicity and photobleaching. By adding lattice structures to the light sheet, the ZEISS Lattice Lightsheet 7 makes this technique available for live cell imaging at subcellular resolution while also allowing microscopists to use their standard sample carriers.

Haem-responsive gene transporter enables mobilization of host haem in ticks.

Ticks, notorious blood-feeders and disease-vectors, have lost a part of their genetic complement encoding haem biosynthetic enzymes and are, therefore, dependent on the acquisition and distribution of host haem. Solute carrier protein SLC48A1, aka haem-responsive gene 1 protein (HRG1), has been implicated in haem transport, regulating the availability of intracellular haem. HRG1 transporter has been identified in both free-living and parasitic organisms ranging from unicellular kinetoplastids, nematodes, up to vertebrates. However, an HRG1 homologue in the arthropod lineage has not yet been identified. We have identified a single HRG1 homologue in the midgut transcriptome of the tick Ixodes ricinus, denoted as IrHRG, and have elucidated its role as a haem transporter. Data from haem biosynthesis-deficient yeast growth assays, systemic RNA interference and the evaluation of gallium protoporphyrin IX-mediated toxicity through tick membrane feeding clearly show that IrHRG is the bona fide tetrapyrrole transporter. We argue that during evolution, ticks profited from retaining a functional hrg1 gene in the genome because its protein product facilitates host haem escort from intracellularly digested haemoglobin, rendering haem bioavailable for a haem-dependent network of enzymes.

Line-field confocal optical coherence tomography for the in vivo real-time diagnosis of different stages of keratinocyte skin cancer: a preliminary study.

BACKGROUND: The treatment of keratinocyte cancers (KC) strictly depends on their differentiation and invasiveness. Non-invasive diagnostic techniques can support the diagnosis in real time, avoiding unnecessary biopsies. This study aimed to preliminarily define main imaging criteria and histological correlations of actinic keratosis (AK), Bowen's disease (BD) and squamous cell carcinoma (SCC) using the novel device line-field confocal optical coherence tomography (LC-OCT). METHODS: Dermoscopy and LC-OCT images of 73 histopathologically confirmed lesions (46 AKs, 11 BD and 16 SCCs) were included in the study. Exemplary lesions (10 AKs, 5 BD and 5 SCCs) were additionally investigated with optical coherence tomography and reflectance confocal microscopy. RESULTS: Most common LC-OCT findings of KC in the descriptive statistics were hyperkeratosis/parakeratosis, disruption of stratum corneum, broadened epidermis, basal and suprabasal keratinocyte atypia, dilated vessels/neoangiogenesis and elastosis/collagen alterations. In the univariate multinomial logistic regression, a preserved DEJ was less common in SCC compared with AK and BD, BD displayed marked keratinocyte atypia involving all epidermal layers (bowenoid pattern), while SCC showed ulceration, increased epidermal thickness, keratin plugs, acantholysis, not visible/interrupted DEJ and epidermal bright particles. LC-OCT increased the diagnostic confidence by 24.7% compared with dermoscopy alone. CONCLUSIONS: Our study describes for the first time specific LC-OCT features of different stages of KC and their histopathological correlates, focusing on keratinocyte morphology and architecture of the epidermis and DEJ. LC-OCT may open new scenarios in the bedside diagnosis, treatment planning and follow-up of KC.

Lesional activation of Tc 17 cells in Behçet disease and psoriasis supports HLA class I-mediated autoimmune responses.

BACKGROUND: Behçet disease (BD) presents with lymphocytic and neutrophilic vasculitis of unknown aetiology. HLA-B*51, the endoplasmic reticulum aminopeptidase 1 (ERAP1), and interleukin 23 receptor (IL23R)/IL12R are genetic risk factors. IL-23 regulates IL-17A, which controls the recruitment and activation of neutrophils. OBJECTIVES: To determine pathological changes in BD skin lesions related to the complex genetic predisposition. METHODS: We characterized the expression of IL-17A and IL-23A in various cell types by immunohistological double staining of sections from papulopustular skin lesions of acute attacks of BD and psoriasis vulgaris lesions, another HLA-class I-associated T-cell-mediated autoimmune disease in which excessive T-cell-derived IL-17A production promotes neutrophil activation. RESULTS: We found that in BD lesions, as in psoriasis, actively expanding CD8+ T cells were the predominant source of IL-17A. IL-17A+ CD8+ T (Tc 17) cells outnumbered infiltrating IL-17A+ CD4+ T cells. Unlike the epidermal localization of CD8+ T cells in psoriasis, Tc 17 cells in BD lesions mainly infiltrated the perivascular tissue and the blood vessel walls of dermis and subcutaneous tissue. They co-localised with a marked IL-23A expression by CD11c+ dendritic cells and CD68+ macrophages. IL-17A expression was associated with extensive recruitment of neutrophils around blood vessels that formed neutrophil extracellular traps (NETs). CONCLUSIONS: In BD, the genetic predisposition may mediate antigen-specific activation and differentiation of a Tc 17 response, possibly targeting endothelial (auto)antigens. Neutrophils recruited by IL-17A in this process may enhance tissue damage by extensive NET formation (NETosis). Thus, the IL-23/IL-17 axis presumably controls neutrophilic inflammation in BD vasculitis in the context of a predominant antigen-specific CD8+ T-cell response.

Line-field optical coherence tomography: in vivo diagnosis of basal cell carcinoma subtypes compared with histopathology.

BACKGROUND: Basal cell carcinoma (BCC) is the most common skin cancer in the general population. Treatments vary from Mohs surgery to topical therapy, depending on the subtype. Dermoscopy, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) have gained a foothold in daily clinical practice to optimize diagnosis and subtype-oriented treatment. The new technique of line-field confocal OCT (LC-OCT) allows imaging at high resolution and depth, but its use has not yet been investigated in larger studies. AIM: To evaluate the main LC-OCT criteria for the diagnosis and subtyping of BCC compared with histopathology, OCT and RCM. METHODS: In total, 52 histopathologically confirmed BCCs were evaluated for imaging criteria. Their frequency, predictive values and ROC curves were calculated. A multinominal regression with stepwise variables selection to distinguish BCC subtypes was performed. RESULTS: Nodular BCCs were mainly characterized by atypical keratinocytes, altered dermoepidermal junction (DEJ), tumour nests in the dermis, dark clefting, prominent vascularization and white hyper-reflective stroma. Superficial BCCs showed a thickening of the epidermis due to a series of tumour lobules with clear connection to the DEJ (string of pearls pattern). Infiltrative BCCs were characterized by elongated hyporeflective tumour strands, surrounded by bright collagen (shoal of fish pattern). The overall BCC subtype agreement between LC-OCT and conventional histology was 90.4% (95% CI 79.0-96.8). CONCLUSION: LC-OCT allows noninvasive, real-time identification of BCCs and their subtypes in vertical, horizontal and three-dimension mode compared with histology, RCM and OCT. Further larger studies are needed to better explore the clinical applications of this promising device.

Development of the ion cyclotron emission diagnostic for the W7-X stellarator.

An ion cyclotron emission (ICE) diagnostic is prepared for installation into the W7-X stellarator, with the aim to be operated in the 2022 experimental campaign. The design is based on the successful ICE diagnostic on the ASDEX Upgrade tokamak. The new diagnostic consists of four B-dot probes, mounted about 72° toroidally away (one module) from the neutral beam injector, with an unobstructed plasma view. Two of the B-dot probes are oriented parallel to the local magnetic field, aimed to detect fast magnetosonic waves. The remaining two probes are oriented poloidally, with the aim to detect slow waves. The radio frequency (RF) signals picked up by the probes are transferred via 50 Ω vacuum-compatible coaxial cables to RF detectors. Narrow band notch filters are used to protect the detectors from possible RF waves launched by the W7-X antenna. The signal will be sampled with a four-channel fast analog-to-digital converter with 14 bit depth and 1 GSample/s sampling rate. The diagnostic's phase-frequency characteristic is properly measured in order to allow measuring the wave vectors of the picked up waves.

Oxidative stress is involved in LLLT mechanism of action on skin healing in rats.

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

Oxidative stress is involved in LLLT mechanism of action on skin healing in rats

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

Charge exchange recombination spectroscopy at Wendelstein 7-X.

The Charge Exchange Recombination Spectroscopy (CXRS) diagnostic has become a routine diagnostic on almost all major high temperature fusion experimental devices. For the optimized stellarator Wendelstein 7-X (W7-X), a highly flexible and extensive CXRS diagnostic has been built to provide high-resolution local measurements of several important plasma parameters using the recently commissioned neutral beam heating. This paper outlines the design specifics of the W7-X CXRS system and gives examples of the initial results obtained, including typical ion temperature profiles for several common heating scenarios, toroidal flow and radial electric field derived from velocity measurements, beam attenuation via beam emission spectra, and normalized impurity density profiles under some typical plasma conditions.

Ex vivo confocal laser scanning microscopy for bullous pemphigoid diagnostics: new era in direct immunofluorescence?

BACKGROUND: Ex vivo confocal laser scanning microscopy (ex vivo CLSM) is a novel diagnostic method allowing rapid, high-resolution imaging of excised skin samples. Furthermore, fluorescent detection is possible using fluorescent-labelled antibodies. OBJECTIVE: To assess the applicability of ex vivo CLSM in the detection of basement membrane (BM) fluorescence in bullous pemphigoid (BP) and to compare its diagnostic accuracy with direct immunofluorescence (DIF) microscopy. METHODS: A total of 81 sections of 49 BP patients with positive DIF microscopy findings were examined using ex vivo CLSM in reflectance and fluorescence mode following staining with fluorescent-labelled IgG and C3 antibodies. RESULTS: Ex vivo CLSM showed an overall performance of 65.3% in identifying BM fluorescence in BP patients. IgG and C3 deposition along the BM was detected in 50% and 45.5% of the patients, respectively. The sensitivity of ex vivo CLSM in detecting BM fluorescence was low (IgG: 50%, C3: 45.5%), but the specificity was high (IgG: 100, C3: 90%). In addition to immunoreactivity, ex vivo CLSM could display subepidermal inflammatory cells similar to histological examination in 84% of patients. CONCLUSIONS: Basement membrane fluorescence could be identified with ex vivo CLSM in the skin sections of BP patients. Ex vivo CLSM enables simultaneous and rapid detection of histopathological and immunofluorescence findings in the same session, albeit with a lower sensitivity than DIF in detecting BM fluorescence.

The influence of temperature during water-quench rapid heat treatment on the microstructure, mechanical properties and biocompatibility of Ti6Al4V ELI alloy.

This study investigates the influence of a rapid heat treatment followed by water-quenching on the mechanical properties of Ti6Al4V ELI alloy to improve its strength for use in implants. Prior to the experiment, a dilatometry test was performed to understand the progressive α-to ß-phase transformation taking place during heating. The results were then used to carry out heat treatments. Microstructure was analysed using SEM, EBSD, EDX and XRD techniques. Vickers micro-hardness, tensile and high cycle rotating bending tests were used to analyse the influence of the $\alpha'$-phase fraction on the strength of the studied alloy. Results show that this process can provide a Ti6Al4V ELI alloy with a better Yield Strength (YS)/uniform deformation (εu) ratio and improved high cycle fatigue strength than those observed in the current microstructure used in medical implants. Lastly, cytotoxicity tests were performed on two types of human cells, namely MG63 osteoblast-like cells and fibroblasts. The results reveal the non-toxicity of the heat-treated Ti6Al4V ELI alloy.

Signatures of a jet cocoon in early spectra of a supernova associated with a γ-ray burst.

Long γ-ray bursts are associated with energetic, broad-lined, stripped-envelope supernovae1,2 and as such mark the death of massive stars. The scarcity of such events nearby and the brightness of the γ-ray burst afterglow, which dominates the emission in the first few days after the burst, have so far prevented the study of the very early evolution of supernovae associated with γ-ray bursts3. In hydrogen-stripped supernovae that are not associated with γ-ray bursts, an excess of high-velocity (roughly 30,000 kilometres per second) material has been interpreted as a signature of a choked jet, which did not emerge from the progenitor star and instead deposited all of its energy in a thermal cocoon4. Here we report multi-epoch spectroscopic observations of the supernova SN 2017iuk, which is associated with the γ-ray burst GRB 171205A. Our spectra display features at extremely high expansion velocities (around 115,000 kilometres per second) within the first day after the burst5,6. Using spectral synthesis models developed for SN 2017iuk, we show that these features are characterized by chemical abundances that differ from those observed in the ejecta of SN 2017iuk at later times. We further show that the high-velocity features originate from the mildly relativistic hot cocoon that is generated by an ultra-relativistic jet within the γ-ray burst expanding and decelerating into the medium that surrounds the progenitor star7,8. This cocoon rapidly becomes transparent9 and is outshone by the supernova emission, which starts to dominate the emission three days after the burst.

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise.

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.