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

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.

[Physical and chemical emergencies in dermatology]. / Physikalische und chemische Notfälle in der Dermatologie.

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.

[S1 guideline on intermittent pneumatic compression (IPC)]. / S1-Leitlinie Intermittierende Pneumatische Kompression (IPK, AIK).

Under the direction of the German Society of Phlebology (Deutsche Gesellschaft für Phlebologie) and in cooperation with other specialist associations, the S1 guideline on intermittent pneumatic compression (IPC) was adopted in January 2018. It replaces the previous guideline from March 2005. The aim of the guideline is to optimize the indication and therapeutic use of IPC in vascular diseases and edema. An extensive literature search of MEDLINE, existing guidelines, and work relevant to the topic was performed. In view of the often methodologically weak study quality with often small numbers of cases and heterogeneous treatment protocols, recommendations can often only be derived from the available data using good clinical practice/expert consensus. Intermittent pneumatic compression is used for thromboembolism prophylaxis, decongestive therapy for edema, and to positively influence arterial and venous circulation to improve clinical symptoms and accelerate ulcer healing in both the outpatient and inpatient care setting. The therapy regimens and devices used depend on the indication and target location. They can be used as outpatient and inpatient devices as well as at home for long-term indications. A target indication is thrombosis prophylaxis. IPC should be used in severe chronic venous insufficiency (stages C4b to C6), in extremity lymphedema as an add-on therapy and in peripheral arterial occlusive disease (PAOD) with stable intermittent claudication or critical ischemia. IPC can be used in post-traumatic edema, therapy-resistant venous edema, lipedema and hemiplegia with sensory deficits and edema. Absolute and relative contraindications to IPC must be taken into account and risks considered and avoided as far as possible. Adverse events are extremely rare if IPC is used correctly. If the indication and application are correct-also as an add-on therapy-it is a safe and effective treatment method, especially for the treatment of the described vascular diseases and edema as well as thrombosis prophylaxis.

[Evidence of compression therapy]. / Evidenz der Kompressionstherapie.

BACKGROUND: Medical compression therapy is widely used to treat phlebologic diseases. Compression bandages as well as compression stockings are used. Compression has been identified to be an effective conservative therapy for the healing of venous ulcers and other indications. Thus, the evidence for the use of medical compression therapy and for which indications is presented. MATERIALS AND METHODS: Review and systematic presentation of the evidence-based use of compression. The current literature, guidelines, and consensus statements were searched and the indications for compression therapy are presented. RESULTS: There is a high level of evidence that compression therapy is effective to heal venous ulcers and to prevent recurrent ulcers. The use of compression bandages and hosiery after interventional and surgical procedures for varicose veins is based on experience but not on randomized controlled trials. According to clinical experience, the healing of inflammatory skin diseases (e.g., erythema nodosum, pyoderma gangrenosum, necrobiosis lipoidica, cutaneous leukocytoclastic vasculitis, and psoriasis of the extremities) is supported by compression therapy. Compression therapy in patients suffering from venous ulcers is highly recommended.

The Mercedes flap and its new variants: a 'workhorse' flap for the dermatological surgeon?

BACKGROUND: The plastic reconstruction of defects in problem regions, such as, e.g. the heel, temple, malleolar region, sternum and capillitium, is usually a challenge. OBJECTIVE: We describe the use of the Mercedes flap, a combination of the purse string and advancement flap, and new modifications for use in various body locations. These examples extend the scope of application in tumour surgery of the skin. METHODS: We demonstrate the different techniques and practical application of the repair and evaluate the benefits and limitations. RESULTS: The Mercedes flap and its modifications are an excellent method for repairing various defects in problem locations after tumour surgery of the skin. CONCLUSION: The Mercedes flap and its modifications prove to be a good alternative to other closure types, especially in problem regions such as the shoulder, malleolar region, heel, etc. The procedure is fast and simple, with few side-effects, and proves to be a 'workhorse' flap for the dermatological surgeon.

[Cutaneous changes in long-standing erythropoietic protoporphyria]. / Hautveränderungen bei lange bestehender erythropoetischer Protoporphyrie.

Erythropoietic protoporphyria results in highly increased photosensitivity of the skin. Solar irradiation causes sunburn-like symptoms with erythema, edema and wheals. We report the case of a 60-year-old man suffering from erythropoietic protoporphyria since his childhood who additionally developed chronic cutaneous lichenoid papules in sun-exposed skin areas. Vaporization with both electrocautery and carbon dioxide laser proved to be a successful treatment option.

Chondrocutaneous helix rim advancement flap: two classical and two new modifications for very large defects of the ear.

BACKGROUND: The plastic reconstruction of the ear after microscopically controlled tumor surgery is a particular challenge. The chondrocutaneous helix rim advancement flap (CHRAF) is perfectly suited for the repair of different defects of the helix and even defects beyond. OBJECTIVE: Here, we describe two known and two new modifications of the CHRAF that enlarge the scope of application in tumor surgery of the ear. METHODS: We demonstrate the different techniques and practical application of the repair and evaluate the benefits and limitations. RESULTS: The CHRAF and its modifications is an excellent method for repair of various defects of the helical region of the ear. CONCLUSION: The CHRAF and its modifications proves to be an good alternative to other methods of closure by preserving the anatomical contour and mechanical and acoustic functions in a single-staged procedure with excellent aesthetic results. The two new modifications we introduced here, enlarge the known armentarium for very large defects of the upper pole and the mid-helix of the ear.

W.A.R. scores in patients with chronic leg ulcers: results of a multicentre study.

OBJECTIVE: To assess the individual patient's risk of wound infection using the wounds-at-risk (W.A.R.) score developed by a group of interdisciplinary experts. METHOD: The W.A.R. score is a clinical test in which, based on anamnestic and clinical criteria, wound patients are assigned point values, where a score of less than or equal to 3 indicates a need for antimicrobial treatment. RESULTS: The data of 970 patients (553 women, 417 men) with chronic leg ulcers were evaluated at 10 dermatological wound clinics in different regions within Germany. The age of the patients was between 10 and 100 years (mean of 69.8 years); the duration of the wounds was between 2 months and 68 years (mean of 41.1 months). Wound sizes were between 1 and 736 cm² (mean of 42.8 cm²). Overall, W.A.R. scores of <3 points were found in 73.1% of patients and scores of greater than or equal to 3 were found in 26.9% [corrected] of patients. There were significant differences in W.A.R. scores by regions with respect to the bacterial species detected and the aetiologies of the wounds. CONCLUSION: Our multicentre study is the first evaluation of clinical data using the newly established W.A.R. scores. We were able to show that the W.A.R. scores are able to identify a segment of the patient population for whom it can be assumed that they are prone to an increased risk of wound infections unless appropriate antimicrobial action is taken. The W.A.R. score is a simple clinical score that identifies patients with an increased risk of wound infection.

[Current detection rates of multiresistant gram negative bacteria (3MRGN, 4MRGN) in patients with chronic leg ulcers]. / Aktuelle Nachweisraten multiresistenter Gram-negativer Bakterien (3MRGN, 4MRGN) bei Patienten mit chronischem Ulcus cruris.

BACKGROUND: Due to the increasing problem of antibiotic resistance in gram-negative pathogens, the Commission for Hospital Hygiene and Infection Prevention (KRINKO) decided to establish a new clinically oriented definition of multi-resistance. Gram-negative pathogens with a multidrug-resistance (MRGN) are divided into those with resistance to three (3MRGN) or four (4MRGN) antibiotic groups. PATIENTS AND METHODS: In this multicenter study which was done in ten dermatological wound clinics, the bacteriological swabs from up to 100 patients with chronic leg ulcers per center were analyzed according to the current classification KRINKO and evaluated. RESULTS: Overall, the results of 970 patients (553 women, 417 men) could be evaluated. We found 681 gram-positive and 1155 gram-negative bacteria. Pseudomonas aeruginosa was with a detection-rate of 31.1% the most frequent gram-negative pathogen, followed by Proteus mirabilis with 13.7% and various enterobacteria with 28.6%. According to the current KRINKO classification,eight patients with 4MRGN and 34 patients with 3MRGN could be identified. CONCLUSIONS: Our results demonstrate the current spectrum of bacteria in patients with chronic leg ulcers with a variety of gram-negative pathogens, some of which are classified as multi-drug resistant. As a clinical consequence some of the patients require individualized preventive measures and therapy.

[Special indications for negative pressure wound therapy in dermatologic surgery]. / Besondere Indikationen der Vakuumversiegelungstherapie in der Dermatochirurgie.

In recent years negative pressure wound therapy (NPWT) has gained more and more supporters in dermatologic surgery. NPWT has become one of the standard therapeutic options, especially for non-healing diabetic, venous and arterial ulcers of the legs. When managing large wounds after tumor surgery, NPWT is frequently used to induce granulation tissue and reduce wound size before the wound is closed with split- or full-thickness skin grafts or local flaps. In addition to these well-established uses, NPWT can be also employed for a variety of "new" or rare indications, some of which are presented in this review.

[Dermatobia hominis infection in a 3-year-old child]. / Dermatobia-hominis-Infektion bei einem 3-jährigen Kind.

In the context of increasing travel to the tropics, outpatient services are more frequently confronted with non-domestic diseases in Europe. A 3-year old child presented with a painful tumor of the scalp. After incision of the furuncle-like lesion, we extracted a larva of the botfly Dermatobia hominis. Botflies are mainly encountered in Central and South America; they should be considered if patients demonstrate a furuncle-like lesion and have returned from a holiday in these endemic regions.

[Bitemporal scalp necrosis : a very rare manifestation of giant cell arteritis]. / Bitemporale Skalpnekrose : Eine sehr seltene Manifestation der Riesenzellarteriitis.

A 71-year-old woman developed progressive spreading of bitemporal scalp necrosis within 4 weeks accompanied by headaches, myalgia of the shoulder girdle and muscle weakness that had started a few months previously. No additional diseases were reported. The suspected temporal giant cell arteritis could be confirmed by temporal artery biopsy. Therapy with glucocorticoids led to a rapid resolution of clinical symptoms and was tapered over 18 months. Recovery of the scalp necrosis emerged following second intention healing and split-skin transplantation of necrotic areas after successful wound conditioning. The case study demonstrates a rare and serious complication of temporal arteritis which is often accompanied by a poor prognosis.

Human leucocyte antigen class I and class II antigen expression in malignant fibrous histiocytoma, fibrosarcoma and dermatofibrosarcoma protuberans is significantly downregulated.

BACKGROUND: Abnormalities in the expression of human leucocyte antigens (HLA) by tumour cells impair cellular immune responses promoting immune evasion and tumour survival. To date, studies analysing HLA class I and class II expression levels in malignant fibrous histiocytomas, fibrosarcomas and dermatofibrosarcoma protuberans are limited. AIMS: Therefore, we investigated the in vivo expression profile of HLA class I and class II antigens in 99 malignant fibrous histiocytomas, 20 fibrosarcomas and 34 dermatofibrosarcoma protuberans from different anatomical sites. MATERIAL AND METHODS: Immunohistochemistry using monoclonal antibodies to HLA class I and class II antigens was used to define the expression levels of these antigens on respective tumour samples. RESULTS: Frequent loss or downregulation of HLA class I and class II expression in malignant fibrous tumours was observed for the different types of tumours examined. DISCUSSION: The data presented suggest for the first time a high frequency of HLA class I and class II abnormalities in malignant fibrous histiocytomas, fibrosarcomas and dermatofibrosarcoma protuberans in vivo. CONCLUSION: This information might be useful in the practical and clinical design of tumour vaccination strategies.

Loss of interferon-gamma inducibility of the MHC class II antigen processing pathway in head and neck cancer: evidence for post-transcriptional as well as epigenetic regulation.

BACKGROUND: Abnormalities of the major histocompatibility complex (MHC) antigens by tumour cells impair the cellular immune response and promote tumour evasion from immune surveillance. So far, studies analysing the MHC class II expression levels in head and neck cancer have been limited. OBJECTIVES: Therefore, we investigated the constitutive and interferon (IFN)-gamma-regulated expression profiles of MHC class II antigen processing machinery (APM) in various head and neck cancer cell lines and also analysed the MHC class II expression in head and neck cancer lesions. METHODS: Using immunohistochemistry, flow cytometry, and reverse transcriptase-polymerase chain reaction analyses we investigated the expression pattern of various components of the MHC class II APM in biopsies and cell lines from head and neck cancers. Furthermore, we analysed the class II transactivator (CIITA) and HLA-DR promoter activity in head and neck cancer cells by transient transfection of specific luciferase promoter constructs and finally studied the methylation pattern of the CIITA promoter using methylation sensitive restriction enzymes. RESULTS: Head and neck cancer cell lines analysed in vitro lacked constitutive MHC class II surface expression. Despite the IFN-gamma-mediated induction at the mRNA level, six out of 10 cell lines did not show any relevant MHC class II surface expression. This phenomenon might be attributed to a post-transcriptional dysregulation of specific MHC class II APM components. One cell line displayed a loss of IFN-gamma-induced CIITA-expression that corresponded to impaired MHC class II surface expression, which could be linked to hypermethylation of the IFN-gamma-responsive CIITA-promoter IV. In vivo, immunohistochemistry analyses of 35 patients revealed that about 86% of head and neck cancer tissues exhibit a negative or only marginally positive staining, whereas 14% displayed a heterogeneous or highly positive MHC class II surface expression. There was no statistical correlation between tumour differentiation and the MHC class II expression in head and neck cancer lesions. CONCLUSIONS: Taken together these results suggest a high frequency of MHC class II abnormalities in head and neck cancer in vitro and in vivo, which could occur at different steps of the antigen processing pathway. This information may have a significant impact on practical and clinical aspects of tumour immunotherapeutic strategies.