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In addition to venous and lymphatic diseases, there is increasing scientific evidence that inflammatory dermatoses of the legs are also indications for compression therapy. Specifically, diseases such as pyoderma gangrenosum, livedoid vasculopathy, cutaneous vasculitides, necrobiosis lipoidica, psoriasis, or erysipelas are conditions for which adjunctive compression therapy may be used when manifestations occur on the lower extremities. When inflammatory dermatoses are accompanied by edema, compression therapy is not an off-label use. Especially because of the often problematic pain symptoms, compression therapy can be performed with low resting pressures around 20 mmHg, especially in inflammatory dermatoses.In this review article, the current scientific aspects of compression therapy in inflammatory dermatoses of the legs and the corresponding limitations are presented in a differentiated manner.

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The polymeric ouzo effect is an energy-efficient and robust method to create nanoparticles with biologically degradable polymers. Usually, a discontinuous or semi-continuous process is employed due to its low technical effort and the fact that the amount of dispersions needed in a laboratory is relatively small. However, the number of particles produced in this method is not enough to make this process economically feasible. Therefore, it is necessary to improve the productivity of the process and create a controllable and robust continuous process with the potential to control parameters, such as the particle size or surface properties. In this study, nanoparticles were formulated from polycaprolactone (PCL) in a continuous process using additively manufactured micromixers. The main goal was to be able to exert control on the particle parameters in terms of size and zeta potential. The results showed that particle size could be adjusted in the range of 130 to 465 nm by using different flow rates of the organic and aqueous phase and varying concentrations of PCL dissolved in the organic phase. Particle surface charge was successfully shifted from a slightly negative potential of -14.1 mV to a negative, positive, or neutral value applying the appropriate surfactant. In summary, a continuous process of nanoprecipitation not only improves the cost of the method, but furthermore increases the control over the particle's parameters.

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Erysipelas is a bacterial soft tissue infection caused by ß-haemolytic streptococci that spreads proximally along the lymphatic system of the skin. The entry sites of the pathogens can be minor injuries or chronic wounds. The diagnosis of erysipelas is made clinically by the spreading eythema and overheating of the skin, the reduced general condition with fever and chills as well as by means of serological inflammation parameters and must be distinguished from numerous differential diagnoses.Systemic therapy is carried out with penicillin usually. In local therapy, the value of measures such as compression therapy or cooling is currently still controversial. Long-term therapy of the lymphoedema and the consistent avoidance and treatment of entry sites are essential, especially for the prevention of recurrence.

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OBJECTIVE: Compression therapy is the cornerstone of therapeutic management of patients with chronic venous insufficiency (CVI). This study aimed to evaluate the efficacy and safety of a multicomponent compression system in an unselected population of patients with CVI problems under real-life conditions. METHOD: A prospective, multicentre, observational study with a multicomponent two-bandage compression system (UrgoK2, Laboratoires Urgo, France) was conducted in 103 centres in Germany. Main outcomes included wound healing rate, wound healing progression, assessment of oedema and ankle mobility, local tolerability and acceptance of the compression therapy. RESULTS: A total of 702 patients with venous leg ulcers (VLU) and/or with lower limb oedema due to CVI were treated with the evaluated system for a mean (±standard deviation) duration of 27±17 days. By the last visit, 30.9% of wounds had healed and 61.8% had improved. Limb oedema was resolved in 66.7% of patients and an improvement of ankle mobility was reported in 44.2% of patients. The skin condition under the compression therapy was also considered as improved in 73.9% of patients and a substantial reduction of pain was achieved, both in number of patients reporting pain and in pain intensity. Compression therapy with the evaluated system was 'very well' or 'well' tolerated and 'very well' or 'well' accepted by >95% of patients. These positive outcomes were in line with the general opinion of physicians on the evaluated compression bandages, which were judged 'very useful' or 'useful' for >96.6% of patients. Similar results were reported regardless of the treated condition, VLU and/or limb oedema. CONCLUSION: Real-life data documented in this large observational study of non-selected patients receiving compression therapy in daily practice confirm the benefits and safety profile of the evaluated compression system. This study also confirms the high-level of performance and acceptability of the system, regardless of the characteristics of the wounds or patients at initiation of the treatment. The data support the use of this multicomponent compression system as one first-line intervention in patients with symptoms caused by CVI.

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BACKGROUND: The pressure exerted by a compression device on a part of the body corresponds to the dosage of the compression therapy. Therefore, the pressure course under compression materials should be investigated in different clinical situations. MATERIAL AND METHODS: Pressure measurements were carried out under different compression materials in lying, standing and walking positions within the framework of training, self-experimentation and in patients with venous leg ulcers. RESULTS: The results showed that the pressure varied considerably depending on the material used, the firmness of application, the local configuration (body position) and the time interval between applications. A loss of pressure occurred under each compression therapy, especially under inelastic short-stretch material, mainly due to movement and edema reduction. This pressure loss is decisive for the timing of dressing changes and a reason for the good tolerance of high-pressure levels in mobile patients. CONCLUSION: Low pressures are particularly suitable for edema reduction. Hemodynamic effects require higher pressures (60-80 mmHg). For this purpose, inelastic materials are preferred which enable lower pressures when lying down (40-60 mmHg). As compression bandages are too loosely applied by many users, pressure indicators on bandages or adaptive bandages with templates are helpful to apply the material with the correct pressure. As a consequence of these findings it is postulated that, at least in studies comparing different compression media, pressure measurements should be carried out in the future, whereby the measuring point and body position should be documented.

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BACKGROUND: Luxation of the elbow occurs around the age of 7 years instead of a supracondylar humeral fracture. The most common complication is a fracture of the medial epicondyle of the ulna in the sense of a bony avulsion of the ligament. There are only few case reports regarding collateral injuries of the brachial artery. All authors have described this complication as being very rare. CASE REPORT AND LITERATURE SEARCH: This article reports the case of a 10-year-old boy, who suffered a dorsal luxation of the left elbow. After reduction the left hand was noticeably pale and cold. The diagnostics showed a complete rupture of the brachial artery, associated with a dislocated fracture of the medial epicondyle of the ulna. In addition to the case report, the available literature concerning traumatic rupture of the brachial artery in pediatric elbow dislocation was evaluated. RESULTS: Because of the results of the clinical examination and the Doppler examination with a lack of blood flow in the brachial artery of the left arm, computed tomography angiography was directly performed. The result was a complete interruption of the brachial artery at the level of the left elbow. The brachial artery rupture was treated using a local vein graft from the brachial vein. The fracture of the medial epicondyle of the ulna was treated by open reduction and an osteosynthesis with Kirschner (k) wires was performed. DISCUSSION: The clinical suspicion of an injury of the brachial artery justifies a rapid diagnostic investigation by CT angiography and an open vascular intervention as the only possibility to recreate a sufficient blood flow.

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An impediment to a mechanistic understanding of how some species sense the geomagnetic field ("magnetoreception") is the lack of vertebrate genetic models that exhibit well-characterized magnetoreceptive behavior and are amenable to whole-brain analysis. We investigated the genetic model organisms zebrafish and medaka, whose young stages are transparent and optically accessible. In an unfamiliar environment, adult fish orient according to the directional change of a magnetic field even in darkness. To enable experiments also in juveniles, we applied slowly oscillating magnetic fields, aimed at generating conflicting sensory inputs during exploratory behavior. Medaka (but not zebrafish) increase their locomotor activity in this assay. Complementary brain  activity mapping reveals neuronal activation in the lateral hindbrain during magnetic stimulation. These comparative data support magnetoreception in teleosts, provide evidence for a light-independent mechanism, and demonstrate the usefulness of zebrafish and medaka as genetic vertebrate models for studying the biophysical and neuronal mechanisms underlying magnetoreception.

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The mammalian magnetic sense is predominantly studied in species with reduced vision such as mole-rats and bats. Far less is known about surface-dwelling (epigeic) rodents with well-developed eyes. Here, we tested the wood mouse Apodemus sylvaticus for magnetoreception using a simple behavioural assay in which mice are allowed to build nests overnight in a visually symmetrical, circular arena. The tests were performed in the ambient magnetic field or in a field rotated by 90°. When plotted with respect to magnetic north, the nests were bimodally clustered in the northern and southern sectors, clearly indicating that the animals used magnetic cues. Additionally, mice were tested in the ambient magnetic field with a superimposed radio frequency magnetic field of the order of 100 nT. Wood mice exposed to a 0.9 to 5 MHz frequency sweep changed their preference from north-south to east-west. In contrast to birds, however, a constant frequency field tuned to the Larmor frequency (1.33 MHz) had no effect on mouse orientation. In sum, we demonstrated magnetoreception in wood mice and provide first evidence for a radical-pair mechanism in a mammal.

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The ferrimagnetic mineral magnetite Fe3O4 is biomineralized by magnetotactic microorganisms and a diverse range of animals. Here we demonstrate that confocal Raman microscopy can be used to visualize chains of magnetite crystals in magnetotactic bacteria, even though magnetite is a poor Raman scatterer and in bacteria occurs in typical grain sizes of only 35-120 nm, well below the diffraction-limited optical resolution. When using long integration times together with low laser power (<0.25 mW) to prevent laser induced damage of magnetite, we can identify and map magnetite by its characteristic Raman spectrum (303, 535, 665 cm(-1)) against a large autofluorescence background in our natural magnetotactic bacteria samples. While greigite (cubic Fe3S4; Raman lines of 253 and 351 cm(-1)) is often found in the Deltaproteobacteria class, it is not present in our samples. In intracellular sulfur globules of Candidatus Magnetobacterium bavaricum (Nitrospirae), we identified the sole presence of cyclo-octasulfur (S8: 151, 219, 467 cm(-1)), using green (532 nm), red (638 nm) and near-infrared excitation (785 nm). The Raman-spectra of phosphorous-rich intracellular accumulations point to orthophosphate in magnetic vibrios and to polyphosphate in magnetic cocci. Under green excitation, the cell envelopes are dominated by the resonant Raman lines of the heme cofactor of the b or c-type cytochrome, which can be used as a strong marker for label-free live-cell imaging of bacterial cytoplasmic membranes, as well as an indicator for the redox state.

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Over the past 50 y, behavioral experiments have produced a large body of evidence for the existence of a magnetic sense in a wide range of animals. However, the underlying sensory physiology remains poorly understood due to the elusiveness of the magnetosensory structures. Here we present an effective method for isolating and characterizing potential magnetite-based magnetoreceptor cells. In essence, a rotating magnetic field is employed to visually identify, within a dissociated tissue preparation, cells that contain magnetic material by their rotational behavior. As a tissue of choice, we selected trout olfactory epithelium that has been previously suggested to host candidate magnetoreceptor cells. We were able to reproducibly detect magnetic cells and to determine their magnetic dipole moment. The obtained values (4 to 100 fAm(2)) greatly exceed previous estimates (0.5 fAm(2)). The magnetism of the cells is due to a µm-sized intracellular structure of iron-rich crystals, most likely single-domain magnetite. In confocal reflectance imaging, these produce bright reflective spots close to the cell membrane. The magnetic inclusions are found to be firmly coupled to the cell membrane, enabling a direct transduction of mechanical stress produced by magnetic torque acting on the cellular dipole in situ. Our results show that the magnetically identified cells clearly meet the physical requirements for a magnetoreceptor capable of rapidly detecting small changes in the external magnetic field. This would also explain interference of ac powerline magnetic fields with magnetoreception, as reported in cattle.

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BACKGROUND: Some 40 000 lower limb amputations are performed in Germany each year, 70% of them in diabetics. About 80% of all major amputations may be preventable with the use of new interventional and vascular surgical procedures, particularly on the arteries of the leg and foot. We present the current state of the art in revascularization techniques and evaluate their usefulness for preservation of the lower limb. METHODS: This overview is based on the guidelines for the diagnosis and treatment of peripheral artery disease (PAD) and diabetic foot syndrome (DFS) that have been issued by the American Heart Association (AHA), the American College of Cardiology (ACC), the German Society of Angiology (DGA), the Trans-Atlantic Intersociety Consensus (TASC II), the German Society of Vascular Surgery (DGG), and the German Diabetes Society (DDG). A selective search in PubMed for relevant articles that appeared from 2000 to 2011 was conducted with the search terms "pedal bypass," "vascular intervention crural pedal," and "crural-pedal revascularization." RESULTS: Most of the data on crural and pedal revascularization are derived from small-scale studies. The few comparative studies of interventional treatments and bypass surgery have not revealed any significant differences in outcome, but all studies of revascularization have shown good success rates for lower limb preservation. CONCLUSION: Though the data are still sparse, the high reported rates of limb preservation imply that peripheral revascularization techniques can play a major role in the treatment of chronic critical limb ischemia (CLI). Therefore, these techniques are recommended without exception by the current guidelines.

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