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Due to the corona pandemic and also to the new competence-oriented catalogue of learning objectives in medicine and the master plan for medical studies 2020, the development of digital and practical teaching concepts has experienced a great increase in importance.As a result of this development, it was an important task to establish this combination and incorporate it into the curricular teaching process.The "Toolkit dermatology" was established, which was sent to a total of more than 650 students at German university dermatology clinics. Using educational films, the students were able to practice their skills. In a further development, the toolkit was combined with classroom lectures and the students were asked to evaluate the toolkit online.The vast majority of students (95-100%) clearly stated that the toolkit helped them to develop their practical skills. Some of them were in fact motivated to complete a clinical traineeship/practical tertial year in dermatology (21-88%). The combination of toolkit and subsequent classroom teaching was also rated very positively (82.2%), as this hybrid mode of teaching provided a better understanding.Digital teaching formats as part of the concept of blended learning, i.e. the combination of virtual and analogue teaching formats, are becoming increasingly more important. Solutions for the disadvantages, such as the lack of real interaction and suitable examination formats, still remain to be found; however, the toolkit project demonstrates that hands-on and digital teaching can lead to high student motivation as well as a high educational standard.HINTERGRUND: Im Rahmen der Corona-Pandemie, aber auch durch den neuen kompetenzenorientierten Lernzielkatalog Medizin und den Masterplan Medizinstudium 2020 hat die Entwicklung digitaler und praktischer Lehrkonzepte einen großen Bedeutungszuwachs erfahren.Im Zuge dieser Entwicklungen stellte sich die Aufgabe, diese Kombination zu etablieren und in den curricularen Lehrablauf zu integrieren.Es folgte die Erstellung des „Toolkits Dermatologie“, das an insgesamt mehr als 650 Studierende an deutschen universitären Hautkliniken verschickt wurde. Anhand von Lehrfilmen konnten die Studierenden ihre praktischen Fertigkeiten trainieren. Im weiteren Verlauf wurde das Toolkit in Kombination zu Präsenzveranstaltungen eingesetzt, und die Studierenden konnten das Toolkit online evaluieren.Die überwiegende Mehrheit (95–100 %) der Studierenden gab an, dass das Toolkit ihnen beim Ausbau ihrer praktischen Fertigkeiten geholfen habe. Bei einigen konnte sogar die Motivation für eine Famulatur/PJ(praktisches Jahr)-Tertial in der Dermatologie geweckt werden (21–88 %). Die Verbindung von Toolkit und anschließender Präsenzveranstaltung wurde ebenfalls sehr positiv bewertet (82,2 %), da diese hybride Form der Lehrvermittlung zu einem besseren Verständnis geführt habe.Digitale Lehrformate im Rahmen des Konzeptes „Blended Learning“, also der Kombination von virtuellen und analogen Lehrformaten, gewinnen immer mehr an Bedeutung. Für die Nachteile wie das Fehlen von realer Interaktion und geeigneter Prüfungsformate müssen in Zukunft noch Lösungen gefunden werden. Allerdings zeigt das Toolkit-Projekt, dass eine praktische und digitale Lehre zugleich zu einer hohen Studierendenmotivation und einem hohen Ausbildungsstandard führen kann.

To combat the ongoing COVID-19 pandemic, scientists have been conducting research at breakneck speeds, producing over 52,000 peer-reviewed articles within the first year. To address the challenge in tracking the vast amount of new research located in separate repositories, we developedoutbreak.infoResearch Library, a standardized, searchable interface of COVID-19 and SARS-CoV-2 resources. Unifying metadata from sixteen repositories, we assembled a collection of over 350,000 publications, clinical trials, datasets, protocols, and other resources as of October 2022. We used a rigorous schema to enforce consistency across different sources and resource types and linked related resources. Researchers can quickly search the latest research across data repositories, regardless of resource type or repository location, via a search interface, public API, and R package. Finally, we discuss the challenges inherent in combining metadata from scattered and heterogeneous resources and provide recommendations to streamline this process to aid scientific research.

Optical coherence tomography (OCT) and reflectance confocal laser microscopy (RCM) allow noninvasive imaging diagnostics of the skin. Since the indication for a biopsy in children is generally made cautiously, OCT and KLM can be helpful in the clarification of pediatric skin lesions. In addition, biopsies only represent a snapshot of a small area of the skin, while noninvasive methods allow several locations to be examined over time, so that dynamic changes and the course of therapy can also be determined. In pediatric dermatology, these diagnostic methods are particularly suitable for the clarification of atypical pigment lesions, for infectious dermatoses such as scabies or tinea, and for the diagnosis of inflammatory and degenerative dermatoses.Die optische Kohärenztomographie (OCT) und die konfokale Lasermikroskopie (KLM) ermöglichen eine nichtinvasive bildgebende Diagnostik der Haut. Gerade weil bei Kindern die Indikation für eine Hautbiopsie eher zurückhaltend gestellt wird, können OCT und KLM für die Abklärung von kindlichen Hautveränderungen hilfreich sein. Außerdem stellen Biopsien immer nur eine Momentaufnahme eines kleinen Bezirkes der Haut dar, während die nichtinvasiven Methoden ermöglichen, mehrere Lokalisationen im Zeitverlauf zu untersuchen, sodass auch dynamische Veränderungen und Therapieverläufe sichtbar gemacht werden können. In der pädiatrischen Dermatologie eignen sie sich insbesondere zur Abklärung atypischer Pigmentläsionen, bei infektiösen Dermatosen wie Skabies oder Tinea und zur Diagnostik entzündlicher und degenerativer Dermatosen.

Optical coherence tomography (OCT) is a noninvasive technique, which fulfills the needs of image-guided treatment in dermatology very well. Its use to aid with the diagnosis and decision upon the suitable therapy of non-melanoma skin cancer—towards more and more novel minimally invasive treatments, which require noninvasive imaging devices for diagnosis and therapy control—is already proven. Together with the technical development of the dynamic OCT (D-OCT), which enables the visualization of the vascularization of the skin and its tumors, D-OCT offers many possibilities for image-guided treatment such as OCT-guided laser treatment and surgery and allows for differentiation between different skin tumors and for decisions on optimal therapy for the patient.

Optical coherence tomography (OCT) has become established in routine diagnosis in dermatology only in the last few years. The reason is that the skin is a challenge for OCT as a strong scattering medium, because only a very small proportion of photons is reflected and can be used for imaging. In addition, in most cases a visual assessment or a biopsy is sufficient. Nevertheless, the main field of application in dermatology is the diagnostics of epithelial skin tumors. The OCT is suitable for the early recognition of small, clinically and light microscopically unspecific basal cell carcinomas as well as for the differential diagnosis of other tumors and precancerous lesions. Using OCT, the preoperative measurement of tumor spread, observation of the course and treatment control of non-surgical procedures are possible; therefore, in many cases a biopsy or treatment control can be avoided. Dynamic OCT is a newly developed add on technique to visualize and quantify the superficial blood vessels of the skin. First studies are focused on the evaluation of tumor vessels, wound healing and monitoring of laser therapy. In ophthalmology, OCT diagnostics of basal cell carcinomas on the eyelids as well as for planning and control of eyelid interventions can be of interest.

We investigate the dynamics of ion crystals in zigzag configuration in transverse magnetic field gradients. A surface-electrode Paul trap is employed to trap $^{40}$Ca$^+$ ions and features submerged wires to generate magnetic field gradients of up to 16.3(9) T/m at the ions position. With the gradient aligned in the direction perpendicular to the axis of weakest confinement, along which linear ion crystals are formed, we demonstrate magnetic field gradient induced coupling between the spin and ion motion. For crystals of three ions across their linear-to-zigzag structural transition we perform sideband spectroscopy upon directly driving the spins with a radiofrequency field. Furthermore, we observe the rich excitation spectrum of vibrational modes in a planar crystal comprised of four ions.

Die optische Koharenztomographie (OCT) hat in der Dermatologie erst seit wenigen Jahren ihren Einzug in die Routinediagnostik genommen. Der Grund hierfur ist, dass die Haut fur die OCT trotz ihrer einfachen Zuganglichkeit als stark streuendes Medium eine Herausforderung darstellt, weil nur ein sehr geringer Anteil der Photonen zuruckreflektiert wird und zur Bildgebung genutzt werden kann. In den meisten Fallen ist zudem eine Blickdiagnose oder eine Biopsieentnahme ausreichend. Dennoch ist das Haupteinsatzgebiet der OCT in der Dermatologie die Diagnostik epithelialer Hauttumoren. Hier eignet sich die OCT zur Fruherkennung kleinster, klinisch und auflichtmikroskopisch unspezifischer Basalzellkarzinome ebenso wie zur Differenzialdiagnose zu anderen Tumoren und Prakanzerosen. Mit der OCT sind eine praoperative Messung der Tumorausdehnung, eine Verlaufsbeobachtung und insbesondere eine Therapiekontrolle bei nichtchirurgischen Verfahren moglich. In vielen Fallen kann so auf eine Biopsie und histologische Kontrolle verzichtet werden. Die dynamische OCT ist eine Weiterentwicklung, mit der die oberflachlichen Blutgefase der Haut visualisiert und quantifiziert werden konnen. Erste Studien fokussieren sich auf die Untersuchung von Tumorgefasen, Wundheilung und Therapieeffekte von Lasertherapien. In der Ophthalmologie kann die OCT-Diagnostik von Basalzellkarzinomen am Lidrand ebenso wie zur Planung und Kontrolle von Lideingriffen von Interesse sein.

Wir berichten von einer 31-jahrigen Anasthesieschwester, welche nach akzidentellem Kontakt mit Sevofluran schwere anaphylaktische Reaktionen zeigte. Wir diagnostizierten eine Sevofluran-Sensibilisierung. Die Anasthesieschwester meidet seitdem strikt OP-Raume mit Einsatz von Sevofluran.

Eine Hautklinik existiert in Augsburg erst seit den Nachkriegsjahren des Zweiten Weltkrieges. Zunachst lag der Schwerpunkt auf der stationaren Therapie von Geschlechtskrankheiten. Mit der Zusammenfuhrung aller Fachabteilungen in das Zentralklinikum in den 80er-Jahren hielt die moderne Dermatologie Einzug. Vorreiter war die Augsburger Hautklinik Anfang der 90er-Jahre mit der Etablierung und Standardisierung der Sentinel-Lymphonodektomie. Heute besteht dieser operative Schwerpunkt weiter, dazu wurde ein Hauttumorzentrum und ein interdisziplinares Allergiezentrum gegrundet. Die Zukunft wird fur die Klinik fur Dermatologie und Allergologie in Augsburg sehr spannend, da eine Umwandlung des stadtischen Hauses in ein Universitatsklinikum mit einer medizinischen Vollfakultat in konkreter Planung ist.

PURPOSE Eleven dermatology clinics from all over Germany took part in our multicenter prospective study with the aim of evaluating 20 MHz sonography in the preoperative diagnosis of malignant melanomas and other pigmented skin tumours. It was to be assessed how effective sonographic measurement of thickness would compare to histology and the clinical palpation of tumour thickness and also the significance of differential diagnosis in sonography of malignant melanomas. METHOD The prospective multicenter study proceed as follows. To the end of August 1997 264 patients with a primary malignant melanoma and 417 patients with benign skin tumours were examined via 20 MHz sonography. Two different examiners estimated the clinical thickness of the tumour by palpation. The tumour was then excised and examined for postoperative correlation with the histology sections. RESULTS The final results showed good correlation between the histological and sonographic estimation of tumour thickness (r = 0.97). Estimation of tumour thickness by palpation showed no correlation with the histology (r = 0.59). Most of the benign (44%) and malignant tumours (38.7%) were spindle shaped. There was no significant difference between the benign and malignant tumour groups in relation to the sonographic presented shapes or echo signs. No different diagnosis could be made. CONCLUSION The technique of high frequency sonography in relation to preoperative diagnosis of malignant melanomas has high priority. In contrast to clinical estimation of tumour thickness, sonography provided a good correlation to histology. The effectiveness of sonography with regard to the valence of the skin tumours is limited and there is no possibility of differentiating between malignant and benign tumours from the morphological face value. Hence, there is a demand for developing a 150 MHz apparatus which will be able to supply evidence regarding the valence of skin tumours.

Phlebologic diseases have become extremely common and have major socio-economic impact. However, the percentage of dermatologists working in phlebology appears to be decreasing according to the data of the German Society of Phlebology (DGP).To investigate the reasons for this development, we--on behalf of the DGP--sent a questionnaire to 120 German Departments of Dermatology in autumn 2012.In 76 returned questionnaires, the number of physicians with additional fellowship training in phlebology averaged 1.5; the average number of those who fulfill the criteria for training fellows in phlebology was 0.9. In 71.1 % of the departments there was a phlebologist. A special phlebologic outpatient clinic existed in 73.7 % of the departments. Sonography with Doppler (89.5 %) and duplex (86.8 %) was used as the most frequent diagnostic tool. For therapy, compression (94.7 %), sclerotherapy (liquid 78.9 %, foam 63.2 %, catheter 18.4 %), endoluminal thermic procedures (radio wave 28.9 %, laser 17.1 %) and surgery (especially crossectomy and stripping 67.1 %, phlebectomy of tributaries 75 %) were used. The average number of treatments was very heterogenous in the different departments.Phlebology definitely plays an important role in dermatology. Most departments fulfill the formal criteria for the license to conduct advanced training in phlebology. A wide spectrum of phlebological diagnostic and therapeutic procedures is available.

Muir-Torre syndrome (MTS) is a rare phenotypic variant of hereditary non-polyposis colorectal carcinoma (HNPCC, Lynch syndrome), in which patients, in addition to visceral carcinomas, develop skin tumors. Multiple keratoacanthomas and basal cell carcinomas with sebocytic differentiation are characteristic as well as multiple benign and malignant tumors of the sebaceous glands, such as sebaceous adenoma, sebaceous epithelioma (sebaceoma) and sebaceous carcinoma. Particularly Cystic tumors of the sebaceous glands are especially suggestive of MTS. In genetically predisposed persons, cutaneous and visceral tumors are diagnosed at an average age of 53 years. Here we present an interesting case of a 65-year-old man in whom molecular genetic tests revealed a novel mutation in the MSH2 gene, leading to a frame shift within the gene.

Onychomycosis is common and can mimic several different nail disorders. Accurate diagnosis is essential to choose the optimum antifungal therapy. The aim of this study was to evaluate the use of confocal laser scanning microscopy (CLSM) and optical coherence tomography (OCT) as new non-invasive diagnostic tools in onychomycosis and to compare them with the established techniques. In a prospective trial, 50 patients with suspected onychomycosis and 10 controls were examined by CLSM and OCT. Parallel KOH preparation, culture, PAS-staining and PCR were performed. PCR showed the highest sensitivity, followed by CLSM, PAS and KOH preparation. OCT offered the second best sensitivity but displayed the lowest specificity. CLSM and KOH preparation showed a high specificity and CLSM offered the best positive predictive value, similar to KOH preparation and OCT. Fungal culture showed the lowest sensitivity and the worst negative predictive value, yet culture and PCR are the only techniques able to identify genus and species. In summary, CLSM was comparable to PAS staining and superior to KOH preparation. Due to the low specificity we assess OCT not as appropriate. In the differentiation of species PCR outplays the fungal culture in terms of time and sensitivity.

Nail disorders can be diagnostically challenging to the dermatologist. Noninvasive methods might help to avoid nail biopsies. More knowledge of the typical features of healthy nails with these techniques is needed for comparison with nail diseases.To describe the typical morphology of healthy nails in optical coherence tomography (OCT) and confocal laser scanning microscopy (CLSM) and to examine the influence of exposure to water on OCT features, nail thickness as well as on transonychial water loss (TOWL) before and after a hand bath. Material and methods In the first part healthy nail plates were investigated with OCT and CLSM. The thickness of layers as well as structural details were defined. Secondly, in a prospective study 30 healthy volunteers conducted 10 hand baths with water within a 2-week period. Measurements of nail thickness and signal intensity by OCT as well as of the TOWL were performed over time.In OCT the unaffected nail plate appears as a band-like, layered structure, yet with some individual differences. In addition, CLSM is able to display single corneocytes and the integrity of their borders. Exposure to water led to a transient rise of TOWL and in nail thickness.OCT, CLSM and TOWL offer valuable noninvasive diagnostic tools for the examination of nails. Using CLSM, microscopic features like integrity of single corneocytes can be investigated. OCT allows determination of nail plate thickness and both OCT and TOWL measurements are able to detect short-term effects after exposure to water.

We discuss the experimental feasibility of quantum simulation with trapped ion crystals, using magnetic field gradients. We describe a micro structured planar ion trap, which contains a central wire loop generating a strong magnetic gradient of about 20 T/m in an ion crystal held about 160 \mu m above the surface. On the theoretical side, we extend a proposal about spin-spin interactions via magnetic gradient induced coupling (MAGIC) [Johanning, et al, J. Phys. B: At. Mol. Opt. Phys. 42 (2009) 154009]. We describe aspects where planar ion traps promise novel physics: Spin-spin coupling strengths of transversal eigenmodes exhibit significant advantages over the coupling schemes in longitudinal direction that have been previously investigated. With a chip device and a magnetic field coil with small inductance, a resonant enhancement of magnetic spin forces through the application of alternating magnetic field gradients is proposed. Such resonantly enhanced spin-spin coupling may be used, for instance, to create Schr\"odinger cat states. Finally we investigate magnetic gradient interactions in two-dimensional ion crystals, and discuss frustration effects in such two-dimensional arrangements., Comment: 20 pages, 13 figures

It is expected that ion trap quantum computing can be made scalable through protocols that make use of transport of ion qubits between sub-regions within the ion trap. In this scenario, any magnetic field inhomogeneity the ion experiences during the transport, may lead to dephasing and loss of fidelity. Here we demonstrate how to measure, and compensate for, magnetic field gradients inside a segmented ion trap, by transporting a single ion over variable distances. We attain a relative magnetic field sensitivity of \Delta B/B_0 ~ 5*10^{-7} over a test distance of 140 \micro m, which can be extended to the mm range, still with sub \micro m resolution. A fast experimental sequence is presented, facilitating its use as a magnetic field gradient calibration routine, and it is demonstrated that the main limitation is the quantum shot noise., Comment: 5 pages, 3 figures

Optical coherence tomography (OCT) is a high-resolution imaging method for in vivo investigation of the human skin. In cross-sectional images of several millimeters length with a penetration depth of the light signal into deeper parts of the dermis, architectural details of the upper skin layers can be assessed and monitored non-invasively over time. The resolution is not high enough to visualize cellular details. Several studies have been performed using OCT to assess its significance as a diagnostic tool for dermatology. The actual technical configuration of OCT is suitable to assess therapeutic effects objectively and to observe skin changes over time.

Radiotherapy is a common treatment of medulloblastoma carcinoma. Radiotherapy-induced ear injuries remain under-evaluated and under-reported. These reactions may have acute or late character, may affect all structures of the hearing organ, and result sensorineural or mixed hearing loss. Thus, reduction in radiation dose to the auditory structures should be attempted whenever possible. The present study describes the technique used in our clinic for the craniospinal irradiation. The doses to different organs at risk are evaluated and compared to other techniques found in the literature.

We explore the effect of the neutrino magnetic moment on neutrino scattering with matter in a core-collapse Supernova. We study the impact both on the neutrino fluxes and on the electron fraction. We find that sizeable modifications require very large magnetic moments both for Dirac and Majorana neutrinos., 7 pages, 6 figures

Skin atrophy is one of the main side-effects of topical corticosteroid therapy. Although the use of high-frequency ultrasound is an established method that has been studied previously, it allows measurements of the slow-reacting dermal thickness only.To investigate the decreasing epidermal thickness, which occurs earlier, we used optical coherence tomography (OCT), a high-resolution noninvasive imaging technique, and compared it with 20-MHz ultrasound and profilometry.In this double-blind placebo-controlled trial 20 healthy volunteers applied four different corticosteroids and the cream base formulation as placebo to the volar part of both arms once a day over a 4-week period. The epidermal thickness, the dermal thickness and the skin surface roughness were assessed using OCT, high-frequency ultrasound and profilometry.Each of the three methods allowed the detection and monitoring of significant corticosteroid-induced skin atrophy and its reversibility. The changes correlated with the potency of the steroids. The epidermal thickness decreased significantly in all test areas, even in the placebo and the untreated fields. As expected, the reduction in epidermal thickness was more pronounced and could be detected earlier by OCT than the reduction of dermal thickness using ultrasound. The epidermal surface roughness investigated using profilometry showed a slight smoothing.OCT allows a simple, fast and noninvasive in vivo measurement of the epidermal thickness. To evaluate the atrophogenic potential of corticosteroids it is more suitable than high-frequency ultrasound as epidermal thickness decreases earlier. In addition, epidermal thickness is a more sensitive indicator of steroid atrophy as the degree of thinning is much higher compared with the dermal atrophy. Profilometry might give further information; however, it would not be suitable for clinical use as the results were generally less pronounced. In the future, OCT might be useful to detect corticosteroid-induced side-effects at the beginning for monitoring the therapy.

An established commercial cream containing polidocanol and urea has been tested in double-blind, randomised clinical studies, in comparison with a new lotion formulation, that has been developed for extensive treatment of the whole body. The studies were carried out in 19 healthy volunteers and 30 atopic eczema patients with itching and dry skin. The results show that the cream and the lotion have very good skin tolerance, significantly increased skin moisture and skin lipids and have fast-onset anti-itching efficacy. Both products are highly effective for the treatment of itching and dry skin of patients with atopic eczema.

Optical coherence tomography (OCT) is a non-invasive technique for morphological investigation of tissue. Since its development in the late 1980s it is mainly used as a diagnostic tool in ophthalmology. For examination of a highly scattering tissue like the skin, it was necessary to modify the method. Early studies on the value of OCT for skin diagnosis gave promising results.The OCT technique is based on the principle of Michelson interferometry. The light sources used for OCT are low coherent superluminescent diodes operating at a wavelength of about 1300 nm. OCT provides two-dimensional images with a scan length of a few millimeters (mm), a resolution of about 15 microns and a maximum detection depth of 1.5 mm. The image acquisition can be performed nearly in real time. The measurement is non-invasive and with no side effects.The in vivo OCT images of human skin show a strong scattering from tissue with a few layers and some optical inhomogeneities. The resolution enables the visualization of architectural changes, but not of single cells. In palmoplantar skin, the thick stratum comeum is visible as a low-scattering superficial well defined layer with spiral sweat gland ducts inside. The epidermis can be distinguished from the dermis. Adnexal structures and blood vessels are low-scattering regions in the upper dermis. Skin tumors show a homogenous signal distribution. In some cases, tumor borders to healthy skin are detectable. Inflammatory skin diseases lead to changes of the OCT image, such as thickening of the epidermis and reduction of the light attenuation in the dermis. A quantification of treatment effects, such as swelling of the horny layer due to application of a moisturizer, is possible. Repeated measurements allow a monitoring of the changes over time.OCT is a promising new bioengineering method for investigation of skin morphology. In some cases it may be useful for diagnosis of skin diseases. Because of its non-invasive character, the technique allows monitoring of inflammatory diseases over time. An objective quantification of the efficacy and tolerance of topical treatment is also possible. Due to the high resolution and simple application, OCT is an interesting addition to other morphological techniques in dermatology.

Die Haut ist die Grenze des Korpers zur Umgebung. Die Physiologie beschaftigt sich mit den Funktionen, die das Hautorgan im Kontakt mit auseren Einflussen ausubt. Auf diese Funktionen sowie die relevanten Strukturelemente, die diese beeinflussen, wird im folgenden naher eingegangen.

Eleven dermatology clinics from all over Germany took part in our multicenter prospective study with the aim of evaluating 20 MHz sonography in the preoperative diagnosis of malignant melanomas and other pigmented skin tumours. It was to be assessed how effective sonographic measurement of thickness would compare to histology and the clinical palpation of tumour thickness and also the significance of differential diagnosis in sonography of malignant melanomas.The prospective multicenter study proceed as follows. To the end of August 1997 264 patients with a primary malignant melanoma and 417 patients with benign skin tumours were examined via 20 MHz sonography. Two different examiners estimated the clinical thickness of the tumour by palpation. The tumour was then excised and examined for postoperative correlation with the histology sections.The final results showed good correlation between the histological and sonographic estimation of tumour thickness (r = 0.97). Estimation of tumour thickness by palpation showed no correlation with the histology (r = 0.59). Most of the benign (44%) and malignant tumours (38.7%) were spindle shaped. There was no significant difference between the benign and malignant tumour groups in relation to the sonographic presented shapes or echo signs. No different diagnosis could be made.The technique of high frequency sonography in relation to preoperative diagnosis of malignant melanomas has high priority. In contrast to clinical estimation of tumour thickness, sonography provided a good correlation to histology. The effectiveness of sonography with regard to the valence of the skin tumours is limited and there is no possibility of differentiating between malignant and benign tumours from the morphological face value. Hence, there is a demand for developing a 150 MHz apparatus which will be able to supply evidence regarding the valence of skin tumours.

Changes in skin thickness and echodensity during the spontaneous menstrual cycle, in women taking hormonal contraceptives and pregnant women were investigated by high-frequency (20 MHz) ultrasound. Women with a spontaneous ovulatory menstrual cycle (group I), women taking one-phase contraceptives (group II), women taking three-phase contraceptives (group III) and pregnant women (group IV) were measured at the following locations: proximal and distal forearm and lower leg on both sides. The skin was investigated during three phases of the menstrual cycle: days 2-4 (phase A), days 12-14 (phase B) and days 20-22 (phase C). Oestradiol and progesterone levels were determined at each phase. The pregnant women were investigated 2 weeks prepartal and 6 weeks after delivery. Group I showed a statistically significant increase in the skin thickness from phase A to phase B, but not from phase B to phase C. Group II showed no significant changes in skin thickness, whereas the skin thickness increased from phase A to phase B in group III. In group IV, the skin was significantly thicker prepartal than after delivery. The measured echodensity showed a negative correlation with skin thickness in group III and in pregnant women. We were able to demonstrate that the status of female sex hormones influences the thickness of the skin. These results can be explained by hormone-induced water retention in the skin. Sonography at 20 MHz is able to quantify these effects, which should be considered when performing ultrasound measurement in women.

Six medical students inhabiting a centuries-old, rat-infested house in Lübeck, in northern Germany, were suffering from itching papules and seropapules. Prior to these patients' visit to our institute, their conditions had been diagnosed as pediculosis, scabies, or pulicosis and treated unsuccessfully with the antiparasitic agent lindane (0.3%). The final diagnosis, tropical rat mite dermatitis, was based on the identification of the arthropod Ornithonyssus bacoti, which has an unsegmented body with eight legs. No treatment was recommended, and the dermatitis disappeared within 2 weeks. Measures taken to prevent reinfestation included extermination of the rats and treatment of the rooms of the house with the acaricide benzyl benzoate. Because the mite O. bacoti spends a relatively short time on a host and penetrates the skin for feeding only, the application of an antiparasitic agent is not necessary. If indicated, treatment should be symptomatic.

We describe the influence of radiation trapping on the spatial distribution of the excited-state population in sodium vapor, interacting with a linearly polarized Gaussian laser beam. Counterintuitively the excitation volume experiences a strong spatial shrinking at high optical depth. The interpretation of this nonlocal effect is based on the numerical solution of the stationary Holstein equation, which takes into account the full frequency dependence of the reabsorption probability within the process of diffusion of radiation. The calculations performed are in good qualitative agreement with the spatial effects observed experimentally. \textcopyright{} 1996 The American Physical Society.

The degree of lipodermatosclerosis in chronic venous insufficiency was determined by high-resolution 20 MHz ultrasound. For comparison, skin biopsies were taken and examined by light microscopy. With increasingly extensive sclerosis, ultrasound showed increasing thickness of the dermis with a poorly defined border from the subcutaneous fat. In addition, an echolucent band appeared in the upper dermis, corresponding to regions of glomerular capillaries in histology. In our experience, high-resolution ultrasound examination allows rapid and objective quantification of lipodermatosclerosis.

33 legs of patients with chronic venous insufficiency and 21 legs of healthy persons were examined by high resolution 20 MHz ultrasound. With increasing lipodermatosclerosis--which was most pronounced in the medium part of the lower leg--an increase of thickness and a decrease of echo density of the dermis could be seen. The first sign of decreased density was an echolucent band in the upper part of the dermis. While in healthy subjects dermis and subcutaneous fat were clearly separated in ultrasound, in mild sclerosis differentiation was more difficult; in extensive lipodermatosclerosis it often was not possible to distinguish these parts of the skin. Localisation and extent of lipodermatosclerosis can be well demonstrated and evaluated by 20 MHz ultrasound.

2050 Background: The epidermal growth factor receptor (EGFR) is commonly amplified, overexpressed, and mutated in glioblastoma (GBM). Anti-EGFR treatments have shown to be associated with EGFR deletion mutant variant III (EGFRvIII) expression in presence of PTEN expression, suggesting a prognostic role of EGFRvIII expression. We determined molecular biomarkers and correlated these with outcome in the GERT trial. Methods: To date, 39 patients were treated within the GERT protocol (Combs SE et al., 2006) evaluating radiochemotherapy (RCHT) with temozolomide (TMZ) and weekly CTX. Pretreatment paraffin-embedded tumor tissue of 32 patients was available for molecular analysis. Twenty-three patients were male, 9 were female. Median age was 49 years. We analyzed amplification of EGFR, expression of EGFR, EGFRvIII, the tumor-suppressor PTEN and O(6)-methylguanine DNA methyltransferase (MGMT) gene promoter methylation. Results: Median follow-up was 12 months. Overall survival (OS) at 12 and 24 months was 89% and 42%. Progression-free survival (PFS) was 76% and 45% at 6 and 12 months, respectively. MGMT promoter hypermethylation was detected in 16/32 tumours. Methylated MGMT did not impact PFS or OS (p = 0.48 and p = 0.08). Data on EGFR copy number of 31/32 tumors showed EGFR gene amplification in 11 tumors. EGFR protein expression was found in 23/32 patients. EGFR-amplification did not impact PFS or OS (p = 0.56, p = 0.3). Patients with EGFR expression showed longer PFS (p = 0.05), but unaltered OS (p = 0.06). EGFRvIII was seen in 5/32 patients, only in tumors with EGFR amplification. Expression of EGFRvIII did not influence PFS (p = 0.26) or OS (p = 0.09). Reduced PTEN (22/32) did not influence PFS or OS (p = 0.27, p = 0.85). Outcome was not associated with coexpression of EGFRvIII and PTEN (n = 5); coexpression of EGFR and PTEN (n = 13) significantly influenced PFS (p = 0.005), but not OS (p = 0.10). Conclusions: Expression of EGFR, and coexpression of EGFR/PTEN is associated with significant increase in PFS after RCHT with TMZ and CTX. EGFR-amplification, reduction of PTEN expression and expression of EGFRvIII did not impact PFS nor OS. Randomized data in the primary treatment of GBM might help identify patients for anti-EGFR therapies. [Table: see text]

In 12 normal volunteers the interaction between the metabolic and cardiovascular effects of adrenaline and either a cardioselective (atenolol 150 mg p. o. for 1 week) or a non-selective β-blocker with intrinsic sympathomimetic activity (pindolol 15 mg p. o. for 1 week) were studied. Equiactive doses of the β-blockers were investigated with respect to their metabolic effects. There were profound differences in the metabolic profile of the two substances: the non-cardioselective beta-blocker caused significant inhibition of the lipolytic, glycogenolytic and the growth hormone-releasing effects of adrenaline when compared to the cardioselective agent. The results indicate that, during non-cardioselective beta-blockade, metabolic effects occur which should favourably influence myocardial oxygen consumption by making myocardial performance more economical. © 1981 Springer-Verlag.