38 research outputs found

    Schmincke's Tumor, Carcinoma of the Base of the Tongue c T1-2, cN2c M0 – A Case Report

    Get PDF
    Background: Lymphoepithelial tumors are the most common carcinomas of the nasopharynx. The non-differentiated tumor, also called Schmincke’s tumor, is more prevalent in the African and Chinese population. The incidence of the tumor according to age peaks between 20 and 30 years of age, and after 60 years of age. The tumor is rarely located outside of the nasopharynx. Case Report: This report is about a 73-year-old female patient diagnosed with a tumor of the base of the tongue. The histological result shows a low-grade carcinoma of the squamous epithelium, a lymphoepithelial carcinoma. Conclusion: Despite the tumor’s rare manifestation outside the nasopharynx, one must also consider the non-differentiated carcinoma of lymphoepithelial matrix. Especially due to the well-known early tumor spreading, cervical lymph node swelling on both sides can be recognized as a possible early symptom. First-line therapy consists of primary radiation of the tumor’s primary region and its lymphoid draining channels. Concomitant chemotherapy can be applied. In case of cervical tumor spreading, a neck dissection reduces the risk of local recurrence

    The visibility of IQHE at sharp edges: Experimental proposals based on interactions and edge electrostatics

    Full text link
    The influence of the incompressible strips on the integer quantized Hall effect (IQHE) is investigated, considering a cleaved-edge overgrown (CEO) sample as an experimentally realizable sharp edge system. We propose a set of experiments to clarify the distinction between the large-sample limit when bulk disorder defines the IQHE plateau width and the small-sample limit smaller than the disorder correlation length, when self-consistent edge electrostatics define the IQHE plateau width. The large-sample or bulk QH regime is described by the usual localization picture, whereas the small-sample or edge regime is discussed within the compressible/incompressible strips picture, known as the screening theory of QH edges. Utilizing the unusually sharp edge profiles of the CEO samples, a Hall bar design is proposed to manipulate the edge potential profile from smooth to extremely sharp. By making use of a side-gate perpendicular to the two dimensional electron system, it is shown that the plateau widths can be changed or even eliminated altogether. Hence, the visibility of IQHE is strongly influenced when adjusting the edge potential profile and/or changing the dc current direction under high currents in the non-linear transport regime. As a second investigation, we consider two different types of ohmic contacts, namely highly transmitting (ideal) and highly reflecting (non-ideal) contacts. We show that if the injection contacts are non-ideal, however still ohmic, it is possible to measure directly the non-quantized transport taking place at the bulk of the CEO samples. The results of the experiments we propose will clarify the influence of the edge potential profile and the quality of the contacts, under quantized Hall conditions.Comment: Substantially revised version of manuscript arXiv:0906.3796v1, including new figures et

    Structural Olfactory Nerve Changes in Patients Suffering from Idiopathic Intracranial Hypertension

    Get PDF
    BACKGROUND: Complications of idiopathic intracranial hypertension (IIH) are usually caused by elevated intracranial pressure (ICP). In a similar way as in the optic nerve, elevated ICP could also compromise the olfactory nerve system. On the other side, there is growing evidence that an extensive lymphatic network system around the olfactory nerves could be disturbed in cerebrospinal fluid disorders like IIH. The hypothesis that patients with IIH suffer from hyposmia has been suggested in the past. However, this has not been proven in clinical studies yet. This pilot study investigates whether structural changes of the olfactory nerve system can be detected in patients with IIH. METHODOLOGY/PRINCIPAL FINDINGS: Twenty-three patients with IIH and 23 matched controls were included. Olfactory bulb volume (OBV) and sulcus olfactorius (OS) depth were calculated by magnetic resonance techniques. While mean values of total OBV (128.7±38.4 vs. 130.0±32.6 mm(3), p=0.90) and mean OS depth (8.5±1.2 vs. 8.6±1.1 mm, p=0.91) were similar in both groups, Pearson correlation showed that patients with a shorter medical history IIH revealed a smaller OBV (r=0.53, p<0.01). In untreated symptomatic patients (n=7), the effect was greater (r=0.76, p<0.05). Patients who suffered from IIH for less than one year (n=8), total OBV was significantly smaller than in matched controls (116.6±24.3 vs. 149.3±22.2 mm(3), p=0.01). IIH patients with visual disturbances (n=21) revealed a lower OS depth than patients without (8.3±0.9 vs. 10.8±1.0 mm, p<0.01). CONCLUSIONS/SIGNIFICANCE: The results suggest that morphological changes of the olfactory nerve system could be present in IIH patients at an early stage of disease

    Structural Correlates of Taste and Smell Loss in Encephalitis Disseminata

    Get PDF
    BACKGROUND: Olfactory dysfunction in MS patients is reported in the literature. MRI of the olfactory bulb (OB) is discussed as a promising new testing method for measuring olfactory function (OF). Aim of this study was to explore reasons for and optimize the detection of olfactory dysfunction in MS patients with MRI. MATERIALS AND METHODS: OB and olfactory brain volume was assessed within 34 MS patients by manual segmentation. Olfactory function was tested using the Threshold-Discrimination-Identification-Test (TDI), gustatory function was tested using Taste Strips (TST). RESULTS: 41% of the MS patients displayed olfactory dysfunction (8% of the control group), 16% displayed gustatory dysfunction (5% of the control group). There was a correlation between the OB volume and the number and volume of MS lesions in the olfactory brain. Olfactory brain volume correlated with the volume of lesions in the olfactory brain and the EDSS score. The TST score correlated with the number and volume of lesions in the olfactory brain. CONCLUSION: The correlation between a higher number and volume of MS lesions with a decreased OB and olfactory brain volume could help to explain olfactory dysfunction

    Influence of cyr61 on the chondrogenic differentiation of human chondrocytes

    No full text
    Das CCN Protein CYR61 besitzt eine Reihe außergewöhnlicher biologischer Funktionen. Als ein Molekül der EZM dient es der Regulation zellulärer Aktivitäten wie Adhäsion, Wanderung und Proliferation. Diese Funktionen stehen im Einklang mit der Wirkung von Proteinen, die Zellwachstum und Differenzierung steuern. Die gewebespezifische und zeitlich begrenzte Expression von CYR61 in Mäuseembryonen lieferte bereits erste Hinweise über eine mögliche Beteiligung an der Entwicklung des Skelettsystems. Auf Grundlage dieser Ergebnisse wurde das CYR61 Protein in nachfolgenden Arbeiten als ein neuer, die Chondrogenese regulierender, Faktor identifiziert. Welchen Einfluss dieses Proteins auf den Knorpelstoffwechsel unterschiedlicher humaner Chondrozytenzelllinien hat wurde Gegenstand neuer Untersuchungen. Dieses Interesse bildete die Grundlage zur Themenstellung der vorliegenden Arbeit. Die Wirkung von CYR61 auf die chondrogene Differenzierung sollte anhand zweier verschiedener Zelllinien (C-28/I2 und T/C-28a2) untersucht werden. Hierbei wurde das Expressionsverhalten von unterschiedlichen Chondrozytenmarkern unter der Wirkung von CYR61 untersucht. Die CYR61-abhängigen Effekte wurden durch RT-PCR nachgewiesen und die Ergebnisse unter serumhaltigen sowie serumreduzierten Versuchsbedingungen hierbei miteinander verglichen.The human cysteine rich protein 61 (cyr61)is a member of the CCN family of growth factor inducible immediate early genes. They play an important role in cellular processes such as adhesion, migration and proliferation. The influence of cyr61 on the chondrogenic differentiation of two different chondrocyte cell lines (C-28/I2 und T/C-28a2) was the aim of this work. The expression pattern of different collagens and proteoglycans was detected either in cyr61 stimulated cells and non-cyr61 stimulated cells for confluent and postconfluent cells. Differentiation markers were analyzed at the mRNA level by RT-PCR. To minimize seruminductive effects the experiments were also performed under serumreduced cellculture conditions

    Early Miocene stratigraphy of Central West Anatolia, Turkey: implications for the tectonic evolution of the Eastern Aegean area

    No full text
    WOS: 000243912100005Small-mammalian faunas enable the discrimination and correlation of uppermost Lower Miocene lacustrine sedimentary units in central western Anatolia. On the basis of sequential stratigraphic relationships, early Early Miocene and latest Early Miocene relative ages are suggested for the older lacustrine mass-flow deposits and younger paper shale units, respectively, which are devoid of age-diagnostic fossils. In central western Anatolia, the sequential differences between the uppermost Lower Miocene successions delineate a deformation zone of NE-SW-trending fault blocks separated by vertical faults. This deformation zone, inherited from Late Oligocene tectonics, underwent an early Early Miocene sinistral transtension leading to pull-aparts that were emplaced by granitoids. Limited extension caused the late Early Miocene repetitive up- and down-wards motions of the fault blocks, with variable magnitudes. This led to contrasting subsidence histories in the relevant basinal system. During the latest Early Miocene, fault blocks coalesced into a regional body characterized by uniform slow subsidence and non-extensional deformation facies. The general trend of the above tectonic events can be explained by lateral slab segmentation and progressive asthenospheric wedging, in response to NE-directed and decelerated palaeosubduction in the Aegean. Copyright (C) 2007 John Wiley & Sons, Ltd

    Screening model of metallic nonideal contacts in the integer quantized Hall regime

    No full text
    In this work, we calculate the electron and the current-density distributions both at the edges and the bulk of a two-dimensional electron system, focusing on ideal and nonideal contacts. A three-dimensional Poisson equation is solved self-consistently to obtain the potential profile in the absence of an external magnetic field considering a Hall bar defined both by gates (contacts) and etching (lateral confinement). In the presence of a perpendicular magnetic field, we obtain the spatial distribution of the incompressible strips, taking into account the electron-electron interactions within the Thomas-Fermi approximation. Using a local version of Ohm's law, together with a relevant conductivity model, we also calculate the current distribution. We observe that the incompressible strips can reside either on the edge or at the bulk depending on the field strength. Our numerical results show that, due to a density poor region just in front of the contacts, the incompressible strips are not in direct contact with the injection region when considering nonideal contact configuration. Such a nonideal contact is in strong contrast with the conventional edge channel pictures, hence has a strong influence on transport. We also take into account heating effects in a phenomenological manner and propose a current injection mechanism from the compressible regions to the incompressible regions. The model presented here perfectly agrees with the local probe experiments all together with the formation of hot-spots

    Mid-term outcome with surgery for type B aortic dissections: A single center experience

    No full text
    Background. The approach to acute and chronic type B aortic dissection has changed significantly over the past years. In this aspect, we have reviewed our single-center experience in surgery for type B dissections and compared the current data presented by other centers. Methods: Twenty-nine patients operated at our center for type B aortic dissection (14 acute, 15 chronic) were reviewed over the years between 1996 and 2004. All patient data in addition to immediate and late outcome following surgery were noted. Results: The mean age in acute and chronic groups was 53 +/- 16 versus 62 +/- 12 years, respectively (p = 0.1). Hospital mortality was 4 patients. The mean period in the intensive care unit was 4.2 +/- 3.1 days. Follow-up time was 36 +/- 11 months. Median interval between the initial symptoms and surgery was 3.8 days for acute cases. No patients underwent reoperation in acute, patients; whereas 3 underwent reoperation in the chronic group. False lumen patency rates in acute and chronic dissections were 16.7% versus 46% after 24 months (p< 0.05). Distal anastomoses included both true and false lumens in 83% of the chronic cases with false lumen patency. The mean reoperation-free survival was 79.35 months with standard error of 5.57 months (95% Cl, 68.42 to 90.27) in all patients. Conclusions: Open surgery in acute type B dissections yielded excellent immediate and long-term durability in our series with no false lumen patency or aortic expansion. However, incorporation of both false and true lumina into distal anastomosis in patients with chronic dissection resulted in false lumen patency with aortic expansion
    corecore