44 research outputs found

    Eccrine porocarcinoma of the head: An important differential diagnosis in the elderly patient

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    Background: Eccrine porocarcinoma is a rare malignant tumor of the sweat gland, characterized by a broad spectrum of clinicopathologic presentations. Surprisingly, unlike its benign counterpart eccrine poroma, eccrine porocarcinoma is seldom found in areas with a high density of eccrine sweat glands, like the palms or soles. Instead, eccrine porocarcinoma frequently occurs on the lower extremities, trunk and abdomen, but also on the head, resembling various other skin tumors, as illustrated in the patients described herein. Observations: We report 5 cases of eccrine porocarcinoma of the head. All patients were initially diagnosed as having epidermal or melanocytic skin tumors. Only after histopathologic examination were they classified as eccrine porocarcinoma, showing features of epithelial tumors with abortive ductal differentiation. Characteristic clinical, histopathologic and immunohistochemical findings of eccrine porocarcinomas are illustrated. Conclusion: Eccrine porocarcinomas are potentially fatal adnexal malignancies, in which extensive metastatic dissemination may occur. Porocarcinomas are commonly overlooked, or misinterpreted as squamous or basal cell carcinomas as well as other common malignant and even benign skin tumors. Knowledge of the clinical pattern and histologic findings, therefore, is crucial for an early therapeutic intervention, which can reduce the risk of tumor recurrence and serious complications. Copyright (c) 2008 S. Karger AG, Basel

    Targeted Destruction of Photosensitive Retinal Ganglion Cells with a Saporin Conjugate Alters the Effects of Light on Mouse Circadian Rhythms

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    Non-image related responses to light, such as the synchronization of circadian rhythms to the day/night cycle, are mediated by classical rod/cone photoreceptors and by a small subset of retinal ganglion cells that are intrinsically photosensitive, expressing the photopigment, melanopsin. This raises the possibility that the melanopsin cells may be serving as a conduit for photic information detected by the rods and/or cones. To test this idea, we developed a specific immunotoxin consisting of an anti-melanopsin antibody conjugated to the ribosome-inactivating protein, saporin. Intravitreal injection of this immunotoxin results in targeted destruction of melanopsin cells. We find that the specific loss of these cells in the adult mouse retina alters the effects of light on circadian rhythms. In particular, the photosensitivity of the circadian system is significantly attenuated. A subset of animals becomes non-responsive to the light/dark cycle, a characteristic previously observed in mice lacking rods, cones, and functional melanopsin cells. Mice lacking melanopsin cells are also unable to show light induced negative masking, a phenomenon known to be mediated by such cells, but both visual cliff and light/dark preference responses are normal. These data suggest that cells containing melanopsin do indeed function as a conduit for rod and/or cone information for certain non-image forming visual responses. Furthermore, we have developed a technique to specifically ablate melanopsin cells in the fully developed adult retina. This approach can be applied to any species subject to the existence of appropriate anti-melanopsin antibodies

    Mathematical modelling and the determination of some quality parameters of air-dried bay leaves

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    WOS: 000222759600007Bay leaves (Laurus nobilis L.) were dried at 40, 50 and 60degreesC air temperatures and 5, 10, 15% relative humidities and also under sun and shade in outdoor areas to see whether any significant difference of quality occurs in drying with hot air. During the drying tests with hot air, air flow velocity was held stable at 1.5 in s(-1) and the samples were hung in the drying channels as the surface of the leaves were held parallel to the direction of air flow. To find out the moisture content changes of the samples, weight loss from the leaves were recorded at fixed intervals. Then, the data obtained from the drying tests were applied to various well-known semi-empirical mathematical models of drying. As part of this effort, five well-known models with drying rate constant as a function of air temperature and both temperature and relative humidity were tested for goodness of fit. Furthermore, to determine the effects of the drying conditions on the colour and the amount of essential oil of the bay leaves, fresh leave's and the leaves dried under different conditions were compared. Among all the drying models, the Page model was found to satisfactorily describe the kinetics of convection drying of bay leaves. It was concluded that no significant loss of quality occurs when drying bay leaves at 60degreesC air temperature. (C) 2004 Silsoe Research Institute.All rights reserved Published by Elsevier Ltd

    An excessive coronoid hyperplasia with suspected traumatic etiology resulting in mandibular hypomobility

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    PubMed ID: 22606859There are multiple theories as to the causes of coronoid process hyperplasia of the mandible, including trauma, temporalis muscle hyperactivity, hormonal stimulus, and genetic inheritance. The excess growth of the coronoid process can cause impingement on the zygomatic processes and may result in mandibular hypomobility. A case of an excessive unilateral coronoid hyperplasia with suspected traumatic etiology, which was successfully treated by coronoidectomy and postoperative physiotherapy, is presented. The patient was a 21-year-old man whose maximum mouth opening was 23 mm. The attachments of the temporalis muscle were stripped and the coronoid process was accessed using the Al-Kayat and Bramley approach.1 The coronoid process was then resected via an intraoral pathway. One week after surgery, physiotherapy was started and the maximum mouth opening had increased to 38 mm. In the case presented, a coronoidectomy with postoperative physiotherapy for treatment of coronoid process hyperplasia produced satisfactory results in the correction of coronoidmalar interference. © 2012 by CHROMA, Inc
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