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The classification of thyroid nodules in children is often difficult, especially in pretreated patients with metastatic disease. In osteosarcoma patients, Tc-MDP SPECT/CT is used for primary and follow-up staging. Bone and soft tissue metastases can be revealed because of Tc-MDP imaging of osteoid-producing metastases. We present Tc-MDP SPECT-CT, CT, and ultrasound images of a highly suspicious calcified thyroid lesion in a 17-year-old boy with osteosarcoma. High uptake in Tc-MDP SPECT-CT provides diagnosis of thyroid metastasis of osteosarcoma, which was proven by histopathology.

Unlabelled: Following diagnosis of acute lymphoblastic leukaemia (ALL) in a 10-year-old girl, routine coagulation screening including von Willebrand factor antigen (VWF:Ag), ristocetin cofactor activity (VWF:RCo) and factor VIIIC (FVIII:C) detected no pathological findings. After the first HR2' element of the high-risk group of the ALL-BFM 2000 protocol, the patient demonstrated extensive bleeding symptoms and acquired von Willebrand syndrome was diagnosed. VWF:Ag (13%), VWF:RCo (13%) and FVIII:C (27%) were decreased. Multimer analysis showed a loss of large multimers and a loss in triplet structures. The observed pattern was thought to be typical for monoclonal IgG gammopathy; however, in this case, unexpectedly, biclonal IgM gammopathy (κ and λ) was detected. After treatment with intravenous immunoglobulin over 5 days, coagulation factors increased to normal levels. Although this effect was assumed to be at best only temporary, especially in a case of IgM gammopathy, no further bleeding symptoms have been observed., Trial Registration Number: M208.

The physiological function of an allergen might be an important factor for the allergenicity. The major grass pollen allergen Phl p 1 shows sequence similarities to the consensus sequences of cysteine proteases. However, up to now, the proteolytic activity of Phl p 1 is controversial. The culture supernatant of Phl p 1-transfected clones from Pichia pastoris showed a proteolytic activity but this might be due to Phl p 1 or irrelevant yeast contaminants. To solve this question, we made use of the zymogram technique and improved it. Substrate as well as substrate concentration was changed from 1% casein to 0.25% skimmed milk powder. For staining, we used a colloidal Coomassie stain (RotiBlue) with a higher sensitivity and better practicability than the conventional Coomassie staining. The proteins in the zymogels and in the SDS-PAGE gels showed similar electrophoretic mobility. Furthermore, the zymogels could be blotted and immunostained. Thus, the molecular mass of the proteolytic bands could be determined and directly compared with immunoblotting results. To clearly assign the protease, we separated the culture supernatant of the Phl p 1-transfected P. pastoris clone by affinity chromatography with monoclonal antibody. Our studies demonstrate that the proteolytic activity did not belong to the recombinant allergen but to the yeast proteins. The enzyme was classified by zymogram inhibition tests as a strong serine protease.

Expansins are a family of proteins that catalyze pH-dependent long-term extension of isolated plant cell walls. They are divided into two groups, alpha and beta, the latter consisting of the grass group I pollen allergens and their vegetative homologs. Expansins are suggested to mediate plant cell growth by interfering with either structural proteins or the polysaccharide network in the cell wall. Our group reported papain-like properties of beta-expansin of Timothy grass (Phleum pratense) pollen, Phl p 1, and suggested that cleavage of cell wall structural proteins may be the underlying mechanism of expansin-mediated wall extension. Here, we report additional data showing that beta-expansins resemble ancient and modern cathepsin B, which is a member of the papain (C1) family of cysteine proteinases. Using the Pichia pastoris expression system, we show that cleavage of inhibitory prosequences from the recombinant allergen is facilitated by its N-glycosylation and that the truncated, activated allergen shows proteolytic activity, resulting in very low stability of the protein. We also show that deglycosylated, full-length allergen is not activated efficiently and therefore is relatively stable. Motif and homology search tools detected significant similarity between beta-expansins and cathepsins of modern animals as well as the archezoa Giardia lamblia, confirming the presence of inhibitory prosequences, active site and other functional amino-acid residues, as well as a conserved location of these features within these molecules. Lastly, we demonstrate by site-directed mutagenesis that the conserved His104 residue is involved in the catalytic activity of beta-expansins. These results indicate a common origin of cathepsin B and beta-expansins, especially if taken together with their previously known biochemical properties.

Dietary lectins, present in beans and other edible plant products, pose a potential threat to consumers due to their capacity to induce histamine release from basophils. In this study, we analyzed the capacity of 16 common, in particular dietary, lectins to induce human basophils to secrete IL-4 and IL-13, the key promoters of Th2 responses and IgE synthesis. Several of the lectins, especially concanavalin A, lentil lectin, phytohemagglutinin, Pisum sativum agglutinin and Sambucus nigra agglutinin, triggered basophils to release IL-4 at concentrations of up to 1 ng/10(6) basophils. Lectins with high IL-4-inducing capacity also stimulated the release of IL-13 and histamine. Lectin-induced IL-4 and IL-13 release reached a maximum after 4-6 h and more than 18 h, respectively. Affinoblotting revealed that lectins with the capacity to induce mediator release bind to IgE, suggesting IgE binding as initial step of signal generation. In conclusion, several dietary lectins can trigger human basophils to release IL-4 and IL-13. Since lectins can enter the circulation after oral uptake, they might play a role in inducing the so-called early IL-4 required to switch the immune response towards a Th2 response and type I allergy.

The aim of this in vitro study was to analyze the diagnostic performance of intravascular ultrasound (IVUS) in vessel wall calcifications and to compare the accuracy of mechanical 12.5 and 20 MHz transducers. Fourty-three sections of 10 vessels with signs of arteriosclerotic disease on pathologic examination were examined. Slices 500 microns thick were obtained and examined radiographically at 9 fold magnification. In each section, identical segments were defined, amounting to a total of 344 segments. The IVUS sections were analyzed by 3 experienced readers. For statistical evaluation ROC analysis was performed using magnification radiography as a reference. An area under the curve (AUC) of 0.79 was obtained for the 12.5 transducer and of 0.83 for the 20 MHz transducer. Additionally, sensitivity, specificity, and accuracy were determined. Sensitivity depended on the morphology, size, and density of the calcified lesions. We therefore conclude that the sensitivity of intravascular ultrasound concerning calcified arteriosclerotic plaques is limited and that there is no significant (p < 0.01) difference between mechanical 20 and 12.5 MHz transducers in examining iliac arteries.

Rationale and Objectives: Intravascular ultrasound (IVUS) is an adjunct to contrast angiography that gives additional information concerning the morphology of the vascular wall. The authors examined the accuracy of intravascular ultrasound (IVUS) in the evaluation of calcified lesions within the abdominal aorta and the iliac artery., Methods: Forty-nine human specimens (iliac artery, 26; abdominal aorta, 23) were examined using a 20-MHz 6.0-F ultrasound catheter, followed by magnification radiography of the same specimens using a newly developed microfocus x-ray tube. Magnification radiographs and ultrasound images were divided into identical sectors to analyze the morphology of calcified arteriosclerotic lesions., Results: A total of 644 sectors was analyzed. Sensitivity of intravascular sonography was 70%, specificity 53%. Sensitivity strongly depended on the morphology of the calcified lesions., Conclusion: The detection of calcified arteriosclerotic lesions by means of IVUS revealed a sensitivity of 70% in an in vitro study using human specimens. However, the specificity of IVUS was only 53%, which is basically a random chance occurrence.

Intravascular ultrasound can detect calcified peripheral arteriosclerotic lesions by hyperdense echo patterns and shadowing of subintimal layers. Nevertheless, 20 MHz ultrasound systems have not been validated for the detection of peripheral calcifications; besides, it is unknown whether the depiction of calcified lesions by intravascular ultrasound depends on the morphology of the calcification. Histological evaluation of severely calcified arteries is difficult because the preparation of those specimens often causes artefacts, e.g., fracture of calcified structures. Direct magnification radiography, currently used in forensic medicine or skeleton examination, is based on a minimized focus and enables the edge-enhanced views of calcifications with high discrimination. In this in-vitro-study direct radiological magnification was used to validate intravascular ultrasound. Forty-nine segments of human peripheral arteries were fixed in formalin, examined with intravascular ultrasound and, as a reference, radiographically magnified using a newly developed microfocus x-ray tube. Sensitivity, specificity, positive and negative predictive value, and accuracy of intravascular ultrasound for the detection of calcified wall areas were determined and compared to the appearance (configuration, circumferential and areal expansion, density, number of fragments) of these calcifications. Thicknesses of 110 single calcified structures were estimated on sonograms and radiograms. The overall sensitivity of the 20 MHz intravascular ultrasound system for the detection of calcification in 913 sectors was 70%, specificity 53%, positive predictive value 66%, negative value 58% and accuracy 62%. The depiction of calcified regions by direct magnification radiography showed that the sensitivity strongly depended on the density of the calcification. Sensitivity was 81% with calcified lesions of high density, but only 51% with lesions of low density.(ABSTRACT TRUNCATED AT 250 WORDS)