Phototesting and photoprotection in LE

Photosensitivity and induction of skin lesions following UV radiation is a common problem of patients with cutaneous and systemic forms of lupus erythematosus. The detrimental effect of UV radiation to patients with lupus erythematosus was already recognized in the last century. Skin lesions can now be provoked under standardized conditions allowing the diagnosis and classification of patients with photosensitive disorders. The aim of this review is to give an overview on the history, test procedure and test results in patients with lupus erythematosus

X-ray topographic determination of the granular structure in a graphite mosaic crystal: a three-dimensional reconstruction

Section topographs recorded at different spatial locations and at different rocking angles of a highly oriented pyrolytic graphite (HOPG) crystal allow three-dimensional maps of the local angular-dependent scattering power to be obtained. This is performed with a direct reconstruction from the intensity distribution on such topographs. The maps allow the extraction of information on local structural parameters such as size, form and internal mosaic spread of crystalline domains. This data analysis leads to a new method for the characterization of mosaic crystals. Perspectives and limits of applicability of this method are discussed

Dual energy imaging in mammography: Cross-talk study in a Si array detector

Abstract One of the main limitation to the extensive use of breast-cancer screening as a prevention method is the relatively high X-ray dose released to the patient. A new approach is under study in which two quasi-monochromatic beamswith mean energies of 18.0 and 36.0 keV -are produced simultaneously, starting from an X-ray tube, by means of a monochromator based on a pyrolytic graphite crystal. The two beams are superimposed in space. The removal of the energy components with low content of diagnostic information from the spectrum, leads to a reduction of the dose released to patients maintaining (or improving) the image quality. The two quasi-monochromatic beams impinge on the patient and then are detected with a solid-state array detector; the image results as the difference between the transmitted intensities of the two detected beams. In this work, the performances of two different electronic readouts and three pixel widths of a silicon position sensitive array detector are simulated and described in order to minimize cross-talk effects between adjacent pixels. The use of a detector with spectrometric capabilities is necessary to separate, by means of thresholds, the high energy photons from the low energy ones

X-ray topographic determination of the granular structure in a graphite mosaic crystal : a three-dimensional reconstruction

Section topographs recorded at different spatial locations and at different rocking angles of a highly oriented pyrolytic graphite (HOPG) crystal allow three-dimensional maps of the local angular-dependent scattering power to be obtained. This is performed with a direct reconstruction from the intensity distribution on such topographs. The maps allow the extraction of information on local structural parameters such as size, form and internal mosaic spread of crystalline domains. This data analysis leads to a new method for the characterization of mosaic crystals. Perspectives and limits of applicability of this method are discussed

Silicon strip detectors for two-dimensional soft X-ray imaging at normal incidence

A simple prototype system for static two-dimensional soft X-ray imaging using silicon microstrip detectors irradiated at normal incidence is presented. Radiation sensors consist of single-sided silicon detectors made from 300 mum thick wafers, read by RX64 ASICs. Data acquisition and control is performed by a Windows PC workstation running dedicated LabVIEW routines, connected to the sensors through a PCI-DIO-96 interface. Two-dimensional images are obtained by scanning a lead collimator with a thin slit perpendicular to the strip axis, along the whole detector size; the several strip profiles (slices) taken at each position are then put together to form a planar image. Preliminary results are presented, illustrating the high-resolution imaging capabilities of the system with soft X-rays. (C) 2003 Elsevier B.V. All rights reserved.info:eu-repo/semantics/publishedVersio

Bilateral linear scleroderma "en coup de sabre" associated with facial atrophy and neurological complications

BACKGROUND: Linear scleroderma "en coup de sabre" (LSCS) usually affects one side of the face and head in the frontoparietal area with band-like indurated skin lesions. The disease may be associated with facial hemiatrophy. Various ophthalmological and neurological abnormalities have been observed in patients with LSCS. We describe an unusual case of LSC. CASE PRESENTATION: A 23 year old woman presented bilateral LSCS and facial atrophy. The patient had epileptic seizures as well as oculomotor and facial nerve palsy on the left side which also had pronounced skin involvement. Clinical features of different stages of the disease are presented. CONCLUSIONS: The findings of the presented patient with bilateral LSCS and facial atrophy provide further evidence for a neurological etiology of the disease and may also indicate that classic progressive facial hemiatrophy (Parry-Romberg syndrome) and LSCS actually represent different spectra of the same disease

Spectrum of centrosome autoantibodies in childhood varicella and post-varicella acute cerebellar ataxia

BACKGROUND: Sera from children with post-varicella infections have autoantibodies that react with centrosomes in brain and tissue culture cells. We investigated the sera of children with infections and post-varicella ataxia and related conditions for reactivity to five recombinant centrosome proteins: γγ-enolase, pericentrin, ninein, PCM-1, and Mob1. METHODS: Sera from 12 patients with acute post-varicella ataxia, 1 with post-Epstein Barr virus (EBV) ataxia, 5 with uncomplicated varicella infections, and other conditions were tested for reactivity to cryopreserved cerebellum tissue and recombinant centrosome proteins. The distribution of pericentrin in the cerebellum was studied by indirect immunofluorescence (IIF) using rabbit antibodies to the recombinant protein. Antibodies to phospholipids (APL) were detected by ELISA. RESULTS: Eleven of 12 children with post-varicella ataxia, 4/5 children with uncomplicated varicella infections, 1/1 with post-EBV ataxia, 2/2 with ADEM, 1/2 with neuroblastoma and ataxia, and 2/2 with cerebellitis had antibodies directed against 1 or more recombinant centrosome antigens. Antibodies to pericentrin were seen in 5/12 children with post-varicella ataxia but not in any of the other sera tested. IIF demonstrated that pericentrin is located in axons and centrosomes of cerebellar cells. APL were detected in 75% of the sera from children with post-varicella ataxia and 50% of children with varicella without ataxia and in none of the controls. CONCLUSION: This is the first study to show the antigen specificity of anti-centrosome antibodies in children with varicella. Our data suggest that children with post-varicella ataxia have unique autoantibody reactivity to pericentrin