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Stefan Whrl Robert Loewe Winfried F. Pickl Georg Stingl Stephan N. Wagner 《Journal der Deutschen Dermatologischen Gesellschaft》2005,3(1):39-43
Background: Seizure prophylaxis with phenytoin is a common measure in oncologic patients with brain metastases. In these patients, generalized severe adverse drug reactions such as erythema multiforme (EEM) may occur. However, in a subgroup of patients with brain radiation therapy, EEM‐like lesions develop particularly in the radiation field. Most recently, the acronym EMPACT ( E rythema M ultiforme associated with P henytoin A nd C ranial radiation T herapy) was proposed to specifically describe this syndrome. Patient/Method: Here, we report on EMPACT syndrome in a 46‐year‐old woman. Therapeutic measures included seizure prophylaxis with phenytoin and total brain radiation therapy of brain metastases from bronchial carcinoma. Three weeks after introduction of phenytoin, the patient presented with EEM‐like skin lesions restricted to the original radiation field and facial mucocutaneous involvement. After a few days, the rash spread to the upper part of the body. She was also in poor general condition. Results: The immediate cessation of phenytoin therapy, combined with administration of systemic corticosteroids and high dose immunoglobulins along with intensive local treatment and pain medications, resulted in complete resolution of the skin eruption. Patch testing to phenytoin was positive after 72 hours. Conclusion: EMPACT should be classified as an specific entity among the EEM‐like drug reactions as it only appears after radiotherapy and seizure prophylaxis with the anticonvulsant phenytoin. We propose including specific type IV‐sensitization to phenytoin into the definition of EMPACT. 相似文献
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Television viewing is the most frequent cause of photogenic attacks in daily life. In the present study, we examined 48 photosensitive children and adolescents to find out: 1) whether hypersynchronous activity is induced less often by viewing a PC monitor than a television screen and 2) whether certain images are more likely to cause hypersynchronous activity than others. All subjects were tested for sensitivity to intermittent photic stimulation (IPS) and to a black and white striped pattern on cards. Additionally, all were subjected to stimuli from four different images (vertical black and white striped pattern, geometric figures, text, and a painting by Max Pechstein - 1913, Italian church), presented on a television screen (with an image regeneration frequency of 50 Hz) and on PC screens (with regeneration frequencies of 48 and 100 Hz). A total of 21 non-photosensitive, healthy children and adolescents served as controls. Of the 48 photosensitive subjects 13% were also pattern sensitive (cards), and 33% exhibited screen sensitivity. No differences were found between the three monitor types. However, the hypersynchronous reactivity to the four images presented was significantly different, with high contrast vertical striped pattern being the most provocative. Non-photosensitive subjects did not react to any of the stimuli. The results of the present study show that screen-dependant factors are less important than image-dependant factors. 相似文献
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Takahiro Higuchi Stephan G Nekolla Antanas Jankaukas Axel W Weber Marc C Huisman Sybille Reder Sibylle I Ziegler Markus Schwaiger Frank M Bengel 《Journal of nuclear medicine》2007,48(2):288-294
The combination of small-animal PET and MRI data provides quantitative in vivo insights into cardiac pathophysiology, integrating information on biology and morphology. We sought to determine the feasibility of PET and MRI for the quantification of ischemic injury in the rat model. METHODS: Fourteen healthy male Wistar rats were studied with 18F-FDG PET and cine MRI. Myocardial viability was determined in a transmural myocardial infarction model in 12 additional rats, using 18F-FDG PET and delayed-enhancement MRI with gadolinium-diethylenetriaminepentaacetic acid. All PET was acquired with a dedicated small-animal PET system. MRI was performed on a 1.5-T clinical tomograph with a dedicated small-animal electrocardiographic triggering device and a small surface coil. RESULTS: In normal rats, 18F-FDG uptake was homogeneous throughout the left ventricle. The lowest mean uptake of the 18F-FDG was found in the apical regions (79% +/- 6.0% of maximum) and the highest uptake was in the anterior wall (93% +/- 4.3 % of maximum). Myocardial infarct size as determined by histology correlated well with defects of glucose metabolism obtained with 18F-FDG PET (r = 0.89) and also with delayed-enhancement MRI (r = 0.91). Left ventricular ejection fraction in normal rats measured by cine MRI was 57% +/- 5.4% and decreased to 38% +/- 12.9% (P < 0.001) in the myocardial infarction model. CONCLUSION: Integrating information from small-animal PET and clinical MRI instrumentation allows for the quantitative assessment of cardiac function and infarct size in the rat model. The MRI measurements of scar can be complemented by metabolic imaging, addressing the extent and severity of ischemic injury and providing endpoints for therapeutic interventions. 相似文献
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Benign paroxysmal tonic upgaze is an ill-defined neuro-ophthalmological disorder with onset in infancy. It consists of sudden ocular movements with sustained upward deviation of the eyes. Episodes disappear with time: spontaneous remission occurs within a few months or years without any change in psychomotor development. EEG and neuro-imaging are unrevealing. To date, the pathogenesis of the condition is still unknown. Early recognition of this benign condition minimizes potentially unnecessary investigations and treatments. Herein, we report on 2 additional sporadic cases. 相似文献
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Barry J. Cusack Stephan P. Young Vicki L. Loseke Michelle R. Hurty Loring Beals Richard D. Olson 《Cancer chemotherapy and pharmacology》1992,30(2):145-148
Summary Malnutrition involving protein deficiency, which commonly occurs in cancer patients receiving anthracycline treatment, is considered to be a risk factor for the development of cardiotoxicity. Protein deficiency has been shown to impair the metabolism of drugs such as theophylline and acetaminophen. If protein deficiency also impairs anthracycline metabolism, it could explain at least in part the enchanced anthracycline toxicity associated with malnutrition. We tested this idea by determining the effect of a low- protein, isocaloric diet on doxorubicin pharmacokinetics in rabbits. The animals were randomized into two groups for 8–12 weeks. Rabbits in group 1 received a low-protein (5%), isocaloric diet, whereas those in group 2 received a normal-protein (15%) diet. Both groups (group 1,n=15; group 2,n=14) were given 5 mg/kg doxorubicin by i.v. bolus. After doxorubicin injection, blood samples were obtained over the next 52 h for the measurement of doxorubicin and doxorubicinol plasma concentrations by high-performance liquid chromatography (HPLC) with fluorometric detection. The low-protein diet significantly decreased doxorubicin clearance (48±3 vs 59±4 ml min–1 kg–1;P<0.05), prolonged the terminal climination half-life (28±2 vs 22±2 h;P<0.05), and increased the area under the plasma concentration/time curve extrapolated to infinity (1722±122 vs 1405±71 ng h ml–1;P<0.05) as compared with the values determined for rabbits fed the standard rabbit chow (15% protein). The volume of distribution for doxorubicin was not altered by the low-protein diet. In addition, in rabbits fed the the low-portein diet, the terminal elimination half-life of the alcohol metabolite, doxorubicinol was prolonged (52±5 vs 40±2 h;P<0.05). Thus, a low-protein diet causes a reduction in the ability of rabbits to eliminate doxorubicin and possibly its alcohol metabolite doxorubicinol. If a similar alteration in anthracycline pharmacokinetics occurs in malnourished cancer patients, this phenomenon may contribute to their increased risk of developing cardiotoxicity associated with anthracycline therapy.Supported by the Department of Veterans Affairs and the American Heart Foundation 相似文献
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