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11.
Noriko Kimura Mika Watanabe Tsuneo Ookuma Wakako Miura Takao Noshiro Yukio Miura Hiroshi Nagura 《Endocrine pathology》1994,5(3):178-182
Pheochromocytoma usually shows prominent nuclear atypia, but the presence of such atypical cells is known to be an unreliable
predictor of malignancy. DNA ploidy of pheochromocytomas has been analyzed by flow cytometry or photospectrometry on paraffinem-bedded
tissue, but the results were controversial. We performed DNA analysis on cytology specimens of 11 pheochromocytomas using
an image analysis system. All tumors had a mixed pattern of a large population of diploid cells and a small population of
polyploid cells. DNA content correlated with nuclear size, and larger cells had more DNA content. Such larger tumor cells
had polyploid nuclei, such as 4 C, 8 C, 16 C, and 32 C, in both malignant and benign pheochromocytomas. The larger polyploid
nuclei may result from difficulty of duplication at the mitotic phase of the cell cycle. 相似文献
12.
Y Soini D Kamel M Apaja-Sarkkinen I Virtanen V P Lehto 《Journal of clinical pathology》1993,46(3):218-221
AIMS: To determine the distribution of tenascin in normal and pathological bone marrow. METHODS: 48 different bone marrow lesions were studied immunohistochemically using a monoclonal antibody to tenascin. RESULTS: Tenascin immunoreactivity was found in lesions with increased fibrosis and high numbers of reticular fibres. The strongest immunoreactivity was found in myelofibrosis. Bone marrow from acute and chronic myeloid and lymphatic leukaemias showed weak or moderate immunoreactivity. In hyperplasias inconsistent reticular tenascin immunoreactivity was found; in normal bone marrow, only a few scattered positive fibres were occasionally seen. CONCLUSIONS: Tenascin was generally observed in conditions in which megakaryocytic hyperplasia was a feature. This is in line with the notion that tenascin synthesis in bone marrow fibroblasts is stimulated by TGF-beta which is synthesised by the megakaryocytic lineage. Tenascin also contains EGF-like repeats. It might therefore function as a growth promoter and in this way could also stimulate synthesis of other matrix components. On the other hand, tenascin could function as an adhesive molecule to some cells of the bone marrow. The presence of tenascin in many pathological states of the bone marrow suggests that it may have a role in their pathogenesis and that it also could be a potential marker of disease. 相似文献
13.
Masato Matsuda Mika Sato Hiroki Sakata Takahisa Ogawa Ken-ichiro Yamamoto Taiji Yakushiji Makoto Fukuda Takehiro Miyasaka Kiyotaka Sakai 《Journal of artificial organs》2008,11(3):148-155
When uremic blood flows through dialyzers during hemodialysis, dialysis membrane surfaces are exposed to shear stress and internal filtration, which may affect the surface characteristics of the dialysis membranes. In the present study, we evaluated changes in the characteristics of membrane surfaces caused by shear stress and internal filtration using blood substitutes: water purified by reverse osmosis and 6.7 wt% dextran70 solution. We focused on the levels of a hydrophilic modifier, polyvinylpyrrolidone (PVP), on the membrane surface measured by attenuated total reflectance Fourier transform infrared spectroscopy. Experiments involving 4 h dialysis, 0-144 h shear-stress loading, and 4 h dead-end filtration were performed using polyester-polymer alloy (PEPA) and polysulfone (PS) membranes. After the dialysis experiments with accompanying internal filtration, average PVP retention on the PEPA membrane surface was 93.7% in all areas, whereas that on the PS membrane surface was 98.9% in all areas. After the shear-stress loading experiments, PVP retention on the PEPA membrane surface decreased as shear-stress loading time and the magnitude of shear stress increased. However, with the PS membrane, PVP retention scarcely changed. After the dead-end filtration experiments, PVP retention decreased in all areas for both PEPA and PS membranes, but PVP retention on the PEPA membrane surface was lower than that on the PS membrane surface. PVP on the PEPA membrane surface was eluted by both shear stress and internal filtration, while that on the PS membrane surface was eluted only by internal filtration. 相似文献
14.
Differential diagnosis of chordoma, chondroid, and ependymal tumors as aided by anti-intermediate filament antibodies. 总被引:1,自引:2,他引:1
Six chordomas, nine chondrosarcomas, and three myxopapillary ependymomas of the filum terminale were evaluated immunohistochemically for the expression of intermediate filament proteins by the use of monospecific antibodies against intermediate filament proteins of keratin, vimentin, and glial fibrillary acidic protein (GFAP) type. All chordomas were positive for keratin but negative for GFAP, whereas chondrosarcomas and ependymomas were negative for keratin. Chondrosarcomas showed strong vimentin positivity, whereas ependymomas were positive for GFAP. Chordomas showed desmosomelike junctions by electron microscopy, whereas chondrosarcomas of different types showed no junctions or only primitive ones. By electron microscopy chordomas often showed prominent intermediate filaments also associated with desmosomes, and poorly differentiated chondrosarcomas also showed prominent intermediate filaments. Keratin positivity of chordomas suggests their epithelial nature, while vimentin positivity of chondrosarcomas is in line with their mesenchymal derivation. The results also show that antibodies against different intermediate filament proteins can be applied as diagnostic aids in making the distinction between chordomas, chondroid tumors, and ependymal tumors. 相似文献
15.
Mika Ogata Akinori Sukuya Chizuko Sugizaki Kaori Ikematsu Takanori Imai Hiroshi Tachimoto Motohiro Ebisawa 《Arerugī》2008,57(7):843-852
OBJECTIVE: We investigated the usefulness of skin prick test (SPT) for the diagnosis of egg white (EW) allergy in infants with atopic dermatitis who showed negative to EW CAPRAST, and followed up the EW-CAPRAST in this study. SUBJECTS AND METHODS: Data of negative SPT using Bifurcated needle (BN) were analyzed from the data of 202 atopic dermatitis infants, who had received SPT from January in 2001 to April in 2005. From the negative SPT value (average and standard deviation) positive SPT value was obtained. Among 202 cases, 89 suspected-egg allergy infants with negative IgE CAPRAST against EW at the time of first visit were recruited to examine the usefulness of SPT. Positive conversion of EW-CAPRAST was checked in 78 cases (65: egg allergy+, 13: egg allergy(-)) who had been followed up in our outpatient clinic. RESULTS: Range of negative SPT control value (mean+2SD) using BF among infants could be set as less than 2 mm for wheal and/or 5 mm for erythema. Among 89 suspected-egg allergy infants with negative EW-CAPRAST, 72 infants (80.9%) were diagnosed as egg allergy by the combination of elimination and provocation test, interestingly 39 infants (54.2%) showed positive SPT results. In the follow up study of 78 negative EW-CAPRAST cases, 47 EW-CAPRAST out of 65 egg-allergy cases turned positive later infantile period (mean EW-CAPRAST: 9.6+/-16.7 Ua/ml at 9.9+/-5.6 months old). EW-CAPRAST of 7 cases in 13 non-egg allergies also turned positive in the follow up, however EW-CAPRAST titer was relatively lower compared to that of egg allergies (1.1+/-1.5 Ua/ml at 13.3+/-2.6 months old). CONCLUSIONS: We experienced fairly number of atopic infants with negative EW-CAPRAST at the first outpatient visit, who were later diagnosed as egg allergy. In about half of these cases, SPT egg-allergy infants, three quarter of EW-CAPRAST turned positive around 10 months old. EW-CAPRAST of atopic infants without egg allergy also turned transiently and slightly positive. In the conclusions, SPT seemed to be more useful than EW-CAPRAST for the diagnosis of egg allergy in early infantile period, however provocation test should be required for the definitive diagnosis in suspected-egg allergy infants without any proof of egg-sensitization. 相似文献
16.
17.
H Holth?fer A Miettinen R Paasivuo V P Lehto E Linder O Alfthan I Virtanen 《Laboratory investigation; a journal of technical methods and pathology》1983,49(3):317-326
Frozen sections of human renal carcinomas were studied in indirect immunofluorescence using antibodies against intermediate filaments of cytokeratin, desmin and vimentin type, and against proximal tubular brush border and distal tubular Tamm-Horsfall glycoprotein antigens, as well as with fluorochrome-labeled lectins in an attempt to study the origin and stage of differentiation of renal carcinomas. Eighty per cent of the renal carcinomas expressed the brush border antigens, whereas the Tamm-Horsfall glycoprotein could not be found. Antibodies against epidermal cytokeratins reacted only with collecting ducts in normal kidney, whereas antibodies against cytokeratins of Madin-Darby canine kidney epithelial cell line also reacted with glomerular and tubular epithelium. In 93% of the carcinomas tumor cells showed reactivity with both types of antikeratin antibodies. Vimentin, the cytoskeletal protein of mesenchymal cells, was present in the carcinoma cells of 53% of the tumors, although it was not present in normal tubular epithelium. Moreover, vimentin was expressed together with cytokeratin in the carcinoma cells in 57% of the keratin-positive samples as judged by double immunostaining, whereas the muscle type of intermediate filament protein, desmin, was not seen in the malignant cells. Binding sites for Lotus tetragonolobus agglutinin and soybean agglutinin, normally present in the cells of proximal tubules, were lacking or only faintly detectable in the neoplastic cells. Dolichos biflorus agglutinin, normally present in collecting ducts, was not detected in the tumors. The results show that most renal carcinomas express cytokeratin antigens as a sign of their epithelial origin and also show characteristics of proximal tubular cells. On the other hand, the results indicate that lectin-binding sites typical for normal differentiated tubular cells are profoundly modified in renal carcinomas. Ulex europaeus agglutinin did not bind to the malignant cells but decorated the endothelial cells of the tumors. 相似文献
18.
CD59-antigen (protectin) is a widely distributed glycolipid-anchored inhibitor of complement lysis. CD59 interacts with complement components C8 and C9 during assembly of the membrane attack complex (MAC). To evaluate species specificity of these interactions we have in the present study examined cross-species binding of isolated human and rat CD59 to the terminal complement components C8 and C9. By using primarily soluble CD59 isolated from urine (CD59U) potentially non-specific binding interactions of the phospholipid portion of the membrane forms of CD59 could be avoided. Sucrose density gradient ultracentrifugation analysis showed that human CD59U bound to both human and rat C8 in the SC5b-8 complexes. Similar binding occurred when rat CD59U was used. The degree of binding did not significantly differ between the heterologous and homologous CD59-C8 combinations. C9 from both species inhibited the binding of CD59 to soluble SC5b-8. In ligand blotting analysis human and rat CD59U bound to human and rat C8 alpha gamma-subunit and C9. Binding of human and rat CD59U was stronger to human than rat C9. In plate binding assays the erythrocyte form of CD59 (CD59E) bound to both human and rat C8. Binding of CD59E to heterologous C9 was considerably weaker than to homologous C9. Our results imply that the reciprocal binding sites between C8 and CD59 and to a lesser degree between CD59 and C9 are conserved between human and rat. Interactions of CD59 with the terminal C components are thus species selective but not 'homologously restricted'. 相似文献
19.
M Miettinen H Holthofer V P Lehto A Miettinen I Virtanen 《American journal of clinical pathology》1983,79(1):32-36
Some skin and soft tumors, which generally are assumed to be derived from endothelial cells or blood vessels, were characterized with fluorochrome-labeled Ulex europaeus I agglutinin (UEA I), recently shown to bind specifically to endothelial cells in various normal human tissues. The staining pattern was compared with that obtained with immunostaining using antibodies against factor-VIII-related antigen (FVIII-RAG), a known marker for endothelial cells. The results showed that UEA-I is a specific and a more sensitive marker for the endothelial cells in benign vascular lesions as compared with anti-FVIII-RAG. UEA-I also stained many neoplastic cells of endothelial sarcomas, which generally were negative for FVIII-RAG. Melanomas, anaplastic carcinomas, and other types of sarcomas were negative for both UEA-I and FVIII-RAG. The results suggest that UEA-I lectin is a specific and sensitive adjunct tool in demonstrating endothelial cells and endothelial derivation of human tumors. 相似文献
20.
Basophil histamine release and lymphocyte proliferation tests were examined with latex allergen prepared from surgical gloves in 15 patients with latex contact urticaria. The basophil histamine release test (BHRT) yielded positive results in 13/14 (93%) patients, whereas commercial latex RAST was positive in only 9/15 (60%) patients. Lymphocyte proliferation test (LPT) was positive in 3/15 (20%) patients, suggesting that cell-mediated immune reactions may also occur in latex allergy. However, patch tests to latex were negative and neither were epidermal Langerhans cells able to present latex antigen to T lymphocytes in vitro. 相似文献