Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A combined histologic, immunohistologic, enzyme histochemical, and immunologic study has been carried out in a 7-year-old girl with recurring extramediastinal monocentric giant lymph node hyperplasia of hyaline-vascular type. A large panel of monoclonal and polyclonal antibodies to lymphoid and nonlymphoid cell markers were tested on frozen and paraffin-embedded lymph node tissue as well as on cell suspension and peripheral blood. Tissue enzyme histochemical study, including a conventional hematologic panel, was performed on frozen and plastic-embedded sections. The pattern was dominated by nodular aggregates of round BA-1+ Leu-14+ HLA-DR+ ATPase+ lymphocytes with polyclonal sIgD and sIgM positivity and lacking cIg and BA-2 staining. Leu-1+/Leu-4+, OKT6+, OKT10+, Leu-7+, and CALLA+ cells were few or absent in the nodules, whereas DRC-1+ BA-2+ HLA-DR+ 5'-Nuc+ cells formed a dendritic network in the outer portion of the nodules. No immunoreactivity for lymphoid and nonlymphoid cell markers, including cytokeratin and keratin, was detected in centrinodular histiocytic-like cells. Particularly, the Hassall's-like structures contained a target-like positivity for laminin, and consisted of flattened acid phosphatase (AP), alpha-naphthyl acetate esterase (ANAE), 5'-nucleotidase (5'-Nuc), and adenosine triphosphatase (ATPase) positive cells, whose enzyme profile overlapped with that of the histiocytic-like cells. The extranodular areas were mainly composed of Leu-1+/Leu-4+ lymphocytes with Leu-3a+/OKT4+ phenotype and, to a lesser extent, of OKT6+ OKT10+ lymphoid cells and scattered cells with markers of histiocytic lineage. The abundant vascular component was generally identified by laminin positivity and, in smaller proportion, it was positive for Factor VIII-related antigen. Most of the medium-sized vessels with high endothelium had marked AP, ANAE, and ATPase activities. The process observed resulted from vascularized nodular aggregates of nontransformed B-cells with the phenotype of primary follicle lymphocytes, associated to centrinodular histiocytic-like cells with a distinct enzyme profile.
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PMID:Immunohistochemical, enzyme histochemical, and immunologic features of giant lymph node hyperplasia of the hyaline-vascular type. 242 88

A Sewall Wright strain-2 guinea pig model producing malignant ascites after injection of a diethylnitrosamine-induced hepatocellular carcinoma cell suspension (Line-10) was used to demonstrate the multilayered settling of tumor cells on the peritoneal surface, frequently followed by the formation of papillary projections and the early invasion in a proliferating submesothelial tissue. At the border of tumor cells and the desmoplastic tissue the malignant cells changed their shape and generally two categories were recognized. Often multilayering, atypical flat cells covered the stromal tissue, while mostly rounded ones invaded using their branched penetration processes, being devoid of cationized ferritin, which was only present on the luminal sides of all cellular elements. Flattened malignant cells, penetrating processes and invading cells lost their microvillous surface pattern. The infiltrating cells were often only detectable with the monoclonal antibody 10 TL 40 and the anti-cytokeratin OV TL 12-5, demonstrating the need for immunohistochemistry in diagnosing solitary invading malignant cells in light microscopy. It appeared that still numerous mesothelial cells were found scattered deeply within the desmoplastic tissue. These former lining cells were identified by their junctions and the presence of remnants of basal lamina as well as by their microvillous 5'-nucleotidase activity.
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PMID:Tumor cell settling and early invasion of the peritoneum. 246 62

Using density gradient centrifugation, human trophoblastic cells were enriched from mixed cell populations of enzymatically dispersed first- and third-trimester placentae. Over 95 per cent of the cells recovered were of epithelial (i.e., trophoblastic) origin, as evidenced by their cytokeratin intermediate filament positivity and vimentin negativity, examined using indirect immunofluorescence, and also by their high content of human chorionic gonadotrophin. The activities of key enzymes involved in purine degradation and re-utilization (5'-nucleotidase; AMP-deaminase; hypoxanthine phosphoribosyltransferase (HPRT); xanthine dehydrogenase/oxidase) as well as the total activity of alkaline phosphatase were measured in the trophoblastic cells. A six-fold increase in the trophoblastic alkaline phosphatase activity was noted between the first and third trimester. A 40 per cent decrease was noted in the activity of 5'-nucleotidase, which, on the basis of kinetic properties, appears to have a dominant role in the dephosphorylation of placental nucleoside-5'-monophosphates. The trophoblastic activities of AMP-deaminase, HPRT, and xanthine dehydrogenase/oxidase did not change as a function of the gestational age. In view of the relative activities of the latter two enzymes, hypoxanthine formed in the trophoblast appears more likely to be re-utilized than degraded to uric acid.
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PMID:Activities of key enzymes of purine degradation and re-utilization in human trophoblastic cells. 283 9

"Chondroid chordoma" is a controversial and confusing entity that was originally described by Heffelfinger and colleagues as a biphasic malignant neoplasm possessing elements of both chordoma and cartilaginous tissue. Because the premise for this distinction was based strictly on histomorphologic criteria, the light microscopic, immunohistochemical, and electron microscopic features of the chondroid and chordoid areas of five chondroid chordomas of the skull base were evaluated separately, and compared to five typical chordomas and six low grade chondrosarcomas. Using light microscopy, chondroid chordoma revealed areas that resembled typical chordoma (chordoid areas) and areas that resembled low grade chondrosarcoma (chondroid areas). However, both the chordoid and chondroid areas had an epithelial phenotype and stained strongly for cytokeratin and EMA as well as S-100. 5'-nucleotidase, an enzyme that has been described in chordoma but not in chondrosarcoma, was found in both the chordoid and chondroid areas of one chondroid chordoma. Electron microscopic studies of both the chordoid and chondroid areas in four of the tumors demonstrated both tonofibrils and desmosomes. Chordoma demonstrated immunohistochemical and electron microscopic features that were nearly identical to chondroid chordoma. Chordoma was cytokeratin, EMA, S-100, and 5'-nucleotidase positive. Ultrastructurally, chordoma exhibited variably-sized vacuoles, abundant rough endoplasmic reticulum (RER), and desmosomes with tonofilaments. In contrast to chondroid chordoma, chondrosarcoma consistently stained for only S-100 protein and was cytokeratin, EMA and 5'-nucleotidase negative. Ultrastructurally, chondrosarcoma demonstrated a flocculogranular matrix, glycogen, abundant RER, and scalloped cellular outlines, but lacked desmosomes with tonofilaments. These findings indicate that "chondroid chordoma" is a variant of chordoma with histologic features that may mimic chondrosarcoma. Despite the resemblance of these hyalinized areas to cartilaginous tissue, these tumors retain their epithelial phenotype. Biphasic differentiation is not present. These findings undermine the original premise for distinguishing "chondroid chordoma" from typical chordoma. The authors propose that these tumors be classified as "hyalinized chordomas," rather than "chondroid chordoma," to clarify their histogenesis and avoid confusion with chondrosarcomas of the base of the skull.
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PMID:Chondroid chordoma. A hyalinized chordoma without cartilaginous differentiation. 757 5