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Foltyn W Kos-Kudła B Siemińska L Zemczak A Strzelczyk J Marek B Kajdaniuk D Nowak M Borowska M Jurecka-Lubienicka B 《Endokrynologia Polska》2006,57(2):160-165
Neuroendocrine tumors are frequently associated with other primary malignancies. Plasmablastic lymphoma is a rare, aggressive neoplasm, derived from large B-cell, associated with human immunodeficiency virus infection. Plasmablastic lymphoma cells share many cytomorphologic and immunophenotypic features with plasmablastic cells, causing some diagnostic problems. We present a unique case of coexisting two very uncommon neoplasms: plasmablastic lymphoma and neuroendocrine carcinoma in 54-years-old men. This is the first report of caecum localization of plasmablastic lymphoma. Presented case images diagnostic problems in rare neoplasms. 相似文献
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INTRODUCTION: The aim of the study was to determine the expression of selected adhesive molecules in papillary thyroid carcinoma. MATERIAL AND METHODS: 47 papillary thyroid carcinoma cases and 11 nonmalignant goiter cases were analyzed by immunohistochemistry. RESULTS: Galectin-3 (LGAL3) was a sensitive and specific marker, present in 91% of analyzed tumors and only in 5% of tumor margin. The presence of CA50 was 86% and 3% respectively with only 3% positive non-malignant cases. Cadherin E expression was noted in 91% of primary tumors, in 84% of the surrounding tissue and in 63% of non-malignant goiter. CD44 (DF1485) was observed in 89% of primary tumors and 48% of surrounding tissue; the reaction with BBA10 was more characteristic for metastases. CONCLUSIONS: Our study confirms the high diagnostic value of galectin-3 in papillary thyroid carcinoma and reveals the similar efficiency of CA50. CD44 (DF1485) expression in primary tumor is more intensive than in surrounding tissue, but the diagnostical inportance is not high because it is often observed in benign lesions. Using of BBA10 is more sensitive, but less specific. High expression of cadherin E in benign lesions impairs its diagnostical application in papillary thyroid cancer. 相似文献
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Stepniak D Spaenij-Dekking L Mitea C Moester M de Ru A Baak-Pablo R van Veelen P Edens L Koning F 《American journal of physiology. Gastrointestinal and liver physiology》2006,291(4):G621-G629
Celiac disease is a T cell-driven intolerance to wheat gluten. The gluten-derived T cell epitopes are proline-rich and thereby highly resistant to proteolytic degradation within the gastrointestinal tract. Oral supplementation with prolyl oligopeptidases has therefore been proposed as a potential therapeutic approach. The enzymes studied, however, have limitations as they are irreversibly inactivated by pepsin and acidic pH, both present in the stomach. As a consequence, these enzymes will fail to degrade gluten before it reaches the small intestine, the site where gluten induces inflammatory T cell responses that lead to celiac disease. We have now determined the usefulness of a newly identified prolyl endoprotease from Aspergillus niger for this purpose. Gluten and its peptic/tryptic digest were treated with prolyl endoprotease, and the destruction of the T cell epitopes was tested using mass spectrometry, T cell proliferation assays, ELISA, reverse-phase HPLC, SDS-PAGE, and Western blotting. We observed that the A. niger prolyl endoprotease works optimally at 4-5 pH, remains stable at 2 pH, and is completely resistant to digestion with pepsin. Moreover, the A. niger-derived enzyme efficiently degraded all tested T cell stimulatory peptides as well as intact gluten molecules. On average, the endoprotease from A. niger degraded gluten peptides 60 times faster than a prolyl oligopeptidase. Together these results indicate that the enzyme from A. niger efficiently degrades gluten proteins. Future studies are required to determine if the prolyl endoprotease can be used as an oral supplement to reduce gluten intake in patients. 相似文献
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In between-subjects studies on two groups of women of the same age, we show that women assess male's facial attractiveness differently in the follicular (F) and luteal (L) phases. In the high conception risk phase (F), women tended to give higher scores to male faces than when they were in the luteal phase. During the five first days of the cycle, i.e. when the estrogen level is still low, women assessed men's facial attractiveness relatively highly. We suggest that it is progesterone in the luteal phase that is responsible for lower attractiveness assigned then to male faces. We also tested which anthropometric facial traits or indices influence male attractiveness. We found that assessments of attractiveness were correlated only with mouth height (positively) and the angle between the middle of the mouth and the middle of the eyes (negatively). The results are compared with those from other studies and discussed in the light of evolutionary biology. 相似文献
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Dariusz Ruszkowski Anna Szakiel Elbieta Auguciska Wirginia Janiszowska 《Acta Physiologiae Plantarum》2006,28(3):217-223
Many medicinal plants contain oleanane saponins in roots, however, only scarce data on their biosynthesis in this organ are
available so far, including our previous results concerning Calendula officinalis plant. Thus, the purpose of the present work was to confirm the presumable biosynthetic pathway of oleanolic acid glycosides
in roots of young C. officinalis plants. First of all, the effective method of isolation of protoplasts from C. officinalis roots was established. Then, isolated root protoplasts were supplied with radioactive precursors, [2-14C] mevalonate (MVA) and [3-3H] oleanolic acid (OL) and their transformations were studied with comparison to results obtained with excised roots. The
penetration of both precursors into protoplasts was more rapid and effective than in the case of excised roots. The labeling
of sterols and OL during the incubation with MVA showed that the isoprenoid pathway leading to triterpenoids was operative
in excised roots as well as isolated root protoplasts. Moreover, the transformations of OL into two series of its glycosides,
i.e. glucosides and glucuronides were investigated. It has been shown that both series of OL glycosides are synthesized in isolated
root protoplasts in the same way as in excised roots of young marigold plants. 相似文献
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Lipocalins are a widely distributed group of proteins whose common feature is the presence of six-or eight-stranded beta-barrel in their tertiary structure and highly conservative motifs short conserved region, (SCR) in their amino acid sequences. The presence of three SCRs is typical for kernel lipocalins, while outlier lipocalins have only one or two such regions. Owing to their ability to bind and transport small, hydrophobic molecules, lipocalins participate in the distribution of such substances. However, the physiological significance of lipocalins is not limited to transfer processes. They play an important role in the regulation of immunological and developmental processes, and are also involved in the reactions of organisms to various stress factors and in the pathways of signal transduction. Of special interest is the enzymatic activity found in a few members of the lipocalin family, as well as the interaction with natural membranes, both directly with lipids and through membrane-localized protein receptors. 相似文献