Showing papers by "Markus Meissner published in 2018"

Hidradenitis Suppurativa After Radical Surgery-Long-Term Follow-up for Recurrences and Associated Factors.

Abstract: BACKGROUND Hidradenitis suppurativa (HS) is a chronic debilitating skin disease in inverse body areas. Wide excision is recommended in Hurley Stages II to III, but the rate and symptoms of recurrences in long-term follow-up remain unclear. OBJECTIVE To analyze the allocation of recurrences regarding the operative field, the onset and quality of HS symptoms as well as factors associated with recurrences in long-term follow-up. MATERIAL AND METHODS Forty-eight patients with Hurley Stage III disease who had undergone 91 wide excisions from 2010 to 2015 were clinically examined regarding postoperative complications and allocation and quality of recurrences. To determine the risk of recurrence, possible surgery, and lifestyle-related associated factors were investigated. RESULTS Postoperative recurrences of HS were seen in 54.2%. Most recurrences (inflamed nodules) were detected in a <1-cm margin around the operative field (18.7%). Surgery under tumescence local anesthesia showed symptoms in 40.6% compared with 28.6% under general anesthesia. Increased alcohol consumption (p = .027) but not body mass index (p = .11) or smoking behavior (p = .45) had significant effect on relapse of HS. CONCLUSION Caution must be given especially in surgery with local anesthesia only. Half of patients with HS showed long-term follow-up signs of recurrence after wide excision, most frequently nearby the operation field.

Frontal fibrosing alopecia - review of recent case reports and case series in PubMed.

Abstract: BACKGROUND In his initial publication of frontal fibrosing alopecia (FFA) in 1994, Steven Kossard included six postmenopausal women. A type of cicatricial alopecia, FFA is clinically characterized by frontotemporal hairline recession and loss of eyebrows. In recent years, there has been an increasing number of case reports of FFA in both premenopausal women and men. STUDY OBJECTIVE Review and analysis of the literature on FFA with regard to epidemiology, associated disorders, disease presentation, diagnosis and treatment. METHODS AND MATERIAL We conducted a Pubmed database search for case reports and case series on FFA. Overall, we reviewed and analyzed data from 68 articles, including 932 patients. Apart from epidemiological data such as age, gender or ethnicity, we also assessed other aspects such as predilection sites, associated skin lesions, comorbidities, drugs and treatment response as well as the diagnostic significance of autoantibodies. RESULTS While we were able to confirm and more accurately define some of the data published in the literature, we were unable to reproduce certain assumptions that had previously been made. The high coincidence of FFA and thyroid disease we found in our analysis is particularly significant. CONCLUSIONS The present study provides the most comprehensive review to date of published cases of FFA.

Fast prototyping of microtubes with embedded sensing elements made possible with an inkjet printing and rolling process

Abstract: We present a new fabrication process to create sub-mm micro tubes with embedded conductive patterns. Based on common 2D patterning techniques and a specially designed rolling process, it achieves 3D structures featuring potentially complex, embedded electrical, mechanical and micro-fluidic functions. We demonstrate the advantage in creating freeform electrical conductors around sub-mm tubes, such as needed for a tube-integrated micro heater. The production of the 2D patterns is flexible, and we demonstrate that both additive manufacturing (fast, accessible) and conventional micro-fabrication processes (cleanroom, wafer-scale) are compatible with the rolling process. To adapt the rolling process for high frequency applications, the patterned tracks can be directly electroplated, with good adhesion, to reduce electrical resistance. For the first time, we achieve saddle-geometry NMR micro detectors. They feature 100 wide, 10 thick conductive tracks on 25 thick polyimide film, and were successfully tested in a 500 MHz (11.7 T) NMR spectrometer. Using a 620 diameter coil, we measured the single-shot SNR of deionized water sample, which corresponded to a mole sensitivity of 18.78 , and a water line shape of 1.52/26.8/37.3 Hz (50, 0.55, 0.11% of the maximum height) from a sample volume of only 82 nl.

Directing adipose-derived stem cells into keratinocyte-like cells: impact of medium composition and culture condition.

Abstract: Background Adipose-derived stem cells (ASC) are known to transdifferentiate into a wide range of different cell species in vitro including along the epidermal lineage. This property makes them a promising tool for regenerative medicine to restore the epidermal barrier. Objective This study is dedicated to identify in vitro conditions enabling transdifferentiation to a keratinocyte-like phenotype. In particular, the impact of different culture conditions (media compositions, 2D, 3D cultures) and extracellular matrix (ECM) molecules was evaluated. Methods Adipose-derived stem cells derived from subcutaneous abdominal fat were characterized by stemness-associated markers and subjected to different media. Epithelial differentiation in 2D cultures was monitored by pan-cytokeratin expression using flow cytometry and immunocytochemistry. To evaluate the impact of different ECM molecules on epidermal stratification, 3D cultures were produced, lifted to the air-liquid interface (ALI) and examined by histological analysis and quantitative real-time RT-PCR. Results We identified a medium composition containing retinoic acid, hydrocortisone, ascorbic acid and BMP-4 enabling maximum pan-cytokeratin expression in 2D cultures. Moreover, adhesion to type IV collagen further promotes the pan-cytokeratin expression. When cultures were lifted to the ALI, significant stratification was observed, particularly in supports coated with type IV collagen or fibronectin. Moreover, epidermal differentiation markers (involucrin, cytokeratin 1 and 14) become induced. Conclusion Conditions with hampered wound healing such as non-healing ulcers demand new treatment regimes. The here introduced optimized protocols for transdifferentiation of ASC into keratinocyte-like cells may help to establish more effective treatment procedures.

Frontal fibrosierende Alopezie - Review aktueller Fallbeispiele und Fallserien in PubMed.

Abstract: Hintergrund In der 1994 erschienen Erstpublikation zur frontal fibrosierenden Alopezie (FFA) fasste Steven Kossard sechs Patientinnen, die sich allesamt in der Postmenopause befanden, zusammen. Bei der FFA handelt es sich um eine vernarbende Alopezie, die durch die klinischen Kriterien der frontotemporalen Haarlinienregression und den Verlust der Augenbrauen gekennzeichnet ist. In letzten Jahren wurden zunehmend Fallberichte zur Manifestation in der Pramenopause und bei mannlichen Patienten publiziert. Ziel der arbeit Zusammenfassung und Analyse der verfugbaren Literatur in Pubmed zur FFA bezuglich der Epidemiologie, der Begleiterkrankungen, der Krankheitsprasentation, Diagnostik und Therapie. Material und methoden Die Datenbank Pubmed wurde nach Fallberichten und Fallserien zur FFA durchsucht. Insgesamt wurden 68 Artikel mit insgesamt 932 Patientenfallen eingeschlossen, analysiert und die patientengebundenen Daten ausgewertet. Neben den epidemiologischen Haufigkeiten wie Alter, Geschlecht oder Ethnie wurden zusatzliche Aspekte zu Pradilektionsstellen, assoziierten Hautveranderungen, Begleiterkrankungen, Medikationen und Therapieansprechen sowie die diagnostische Relevanz von Autoantikorpern erfasst. Ergebnisse Teilweise konnten die in Fallserien und Einzelfallberichten publizierten Erkenntnisse bestatigt und besser differenziert werden, wohingegen einzelne Annahmen nicht reproduziert werden konnten. Von besonderer Relevanz ist die in unserer Analyse ermittelte hohe Koinzidenz der FFA mit Schilddrusenerkrankungen. Schlussfolgerungen Die vorliegende Arbeit prasentiert, die bislang umfangreichste Zusammenfassung der in der Literatur zur FFA publizierten Patientenfalle.

Physical Attacks in Dermoscopy: An Evaluation of Robustness for clinical Deep-Learning

Abstract: Deep Learning (DL)-based diagnostic systems are getting approved for usage as fully automatic or secondary opinion products. This development derives from the achievement of expert-level performance by DL across several applications (e.g. dermoscopy and diabetic retinopathy). While recent literature shows their vulnerability to imperceptible digital manipulation of the image data (e.g. through cyberattacks), the performance of medical DL systems under physical world attacks is not yet explored. This problem demands attention if we want to safely translate medical DL research into clinical practice. In this paper, we design the first small-scale prospective evaluation addressing the vulnerability of DL-dermoscopy systems under physical world attacks in absentia of knowledge about the underlying DL-architecture. We publish the entire dataset of collected images as Physical Attacks on Dermoscopy (PADv1) for public use. The evaluation of susceptibility and robustness reveals that such attacks lead to on average 31% accuracy loss across popular DL-architectures. The DL diagnosis is changed by the attack in one of two cases even without any knowledge of the DL method.

Physikalische und chemische Notfälle in der Dermatologie

Abstract: Physical and chemical emergencies are often caused by household or work accidents. Regardless of the medical field and outside specialized clinics, the physician may be confronted with the situation for first or secondary care. The identification of the causing agent and a rapid assessment of the extent and severity of the tissue damage are essential to initiate early transfer to a specialized burn clinic. Grade 2b tissue damage is usually surgically treated. Smaller and superficial injuries can often be conservatively treated. Even supposedly safe and over-the-counter medicines can also lead to serious tissue damage.

Fatty acid receptor GPR120: a novel marker for human melanoma

Abstract: The correlation between ultraviolet radiation of the skin and melanoma incidence in humans is well established. Interestingly, epidemiologic data suggest also a correlation to an increased BMI pointing to metabolic trigger factors in melanoma pathogenesis. To substantiate this connection, we studied

Dropped‐head syndrome in a patient under treatment with the MEK inhibitor trametinib for NRAS‐mutated metastatic melanoma

Abstract: N. Rajan Institute of Genetic Medicine, University of Newcastle upon Tyne, Newcastle upon Tyne, UK; Department of Dermatology, Royal Victoria Infirmary, Newcastle upon Tyne, NE1 3BZ, UK; and Department of Dermatology, James Cook University Hospital, Middlesbrough, North Yorkshire, UK E-mail: neil.rajan@ncl.ac.uk Conflict of interest: the authors declare that they have no conflicts of interest. Accepted for publication 11 February 2017

Pleomorphic lipoma: Correspondence

Abstract: Surgical removal of soft tissue tumors such as lipoma is a common procedure in dermatological surgery. Only in certain cases is a preoperative diagnostic workup required. Imaging studies should be employed in order to better differentiate the tumor from adjacent structures in locations that are difficult to access surgically and to assess the depth of tumor invasion, as well as in cases in which the diagnosis is unclear. We report on a 48-year-old female patient who presented with a three-year history of an enlarging painless neck mass. Physical examination revealed a skin-colored mobile tumor (4.5 × 4.5 cm) in the nuchal region; there was no pain on palpation. Ultrasound imaging showed an encapsulated subcutaneous tumor (Figure 1a). Apart from hypoechoic components (adipose tissue), hyperechoic areas were also noted. Clinically, the mass was primarily consistent with lipoma. Given the atypical hyperechoic areas and for a more accurate assessment of the size of the lesion, we performed magnetic resonance imaging. This showed a solid subcutaneous tumor (2.7 × 1.9 × 3.3 cm) marked by intermediate T1 signal intensity and a hyperintense T2 signal. Administration of contrast agent resulted in inhomogeneous, cloudy contrast uptake. While the muscle fascia did not seem to be infiltrated, the caudal aspect of the lesion appeared somewhat blurred, a radiologically suspicious finding consistent with liposarcoma (Figure 1b–e). Following the urgent recommendation for histological confirmation, the lesion was surgically removed. Gross examination of the specimen revealed a tumor with a smooth capsule and a shiny yellow cut surface (Figure 2). Histology showed a mesenchymal tumor with myxoid, spindle-cell, and lipomatous components, including bizarre multinucleated cells and coarse collagen fibers (Figure 3a, b). No lipoblasts were noted. Immunohistochemically, the neoplastic cells were characterized by CD34 expression (Figure 3c). In order to distinguish this tumor from well-differentiated liposarcoma, additional immunohistochemical stains (CDK4 and MDM2) were performed [1]. These as well as S-100 staining were negative.