Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of a distinctive vascular neoplasm of the spleen in a 3-year-old boy is described. The tumor was characterized histologically by a biphasic growth pattern, with discrete nodular areas composed of atypical round, epithelioid cells with large nuclei and prominent nucleoli, and areas showing an intricate proliferation of vascular channels lined by elongated spindle cells. Immunohistochemical studies showed cytoplasmic staining of the tumor cells with factor VIII-related antigen, Ulex europaeus lectin, and vimentin antibodies. Stains for keratin, actin, desmin, lysozyme, and S-100 protein were negative in the tumor cells. Electron microscopy revealed a fairly cohesive population of cells that contained mature and immature cell junctions, basal lamina material, and surface pinocytotic activity consistent with vascular endothelial cells. Five-year follow-up has shown the patient to be alive and free of disease. This case appears to represent a previously unreported primary vascular neoplasm of the spleen showing combined features of epithelioid and spindle-cell hemangioendothelioma. The lesion should be distinguished from other benign and malignant vascular proliferations of the spleen such as Kaposi's sarcoma, angiosarcoma, and the recently described littoral-cell angioma.
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PMID:Epithelioid and spindle-cell hemangioendothelioma of the spleen. Report of a distinctive splenic vascular neoplasm of childhood. 149 19

Seventeen cases of a novel type of vascular tumor of the spleen are described. The lesions, whose size ranges from minute foci to large nodules almost completely replacing the splenic tissue, are composed of anastomosing vascular channels resembling splenic sinus and have irregular lumina, often featuring papillary projections and cyst-like spaces; they are lined by tall endothelial cells that slough off into the vascular lumina and show hemophagocytosis. Atypical cells are absent and mitotic activity very low. In contrast to normal sinus endothelia, which express only FVIIIag, neoplastic cells express both endothelial (FVIII-AG, BMA 120) and histiocytic (KP1, lysozyme) antigens; occasionally S-100 protein is also present. The morphologic and immunohistochemical findings in this tumor reflect the dual differentiation potential of the reticuloendothelial cells lining the splenic sinus, justifying the term littoral cell angioma, and recognize a distinct entity that is different from other vascular lesions of the spleen, notably angiosarcoma. This distinction is all the more important because the clinical behaviour of this lesion is apparently benign.
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PMID:Littoral cell angioma. A novel splenic vascular lesion demonstrating histiocytic differentiation. 1068 Sep

This paper presents 14 examples of a distinctive cardiovascular lesion. The patients' ages ranged from 5 to 76 years (mean, 51 years). There were seven male patients and seven female patients. All of the lesions were small and represented incidental surgical findings. Ten were attached to the endocardium, three were free-floating in the pericardial cavity, and one was inside a dissecting aneurysm of the ascending aorta. Microscopically, the lesions were enclosed in a fibrinous network and composed of a solid proliferation of round to polygonal cells with centrally located nuclei. Immunohistochemically, the cells were negative for FVIII-related antigen and lysozyme, but they stained positively for keratin, especially when clustered in small micropapillary or tubule-like formations. The nature and pathogenesis of these lesions are uncertain. Their location and some of their microscopic features originally suggested a relationship with the entity described as histiocytoid (epithelioid) hemangioma. However, their intense immunoreactivity for keratin, occasional presentation in the pericardial sac, and marked morphologic similarities with nodular mesothelial hyperplasia as sometimes seen in hernia sacs point toward the alternative possibility of a reactive mesothelial nature. A possible pathogenetic mechanism for the endocardial cases is ingrowth of pericardial mesothelial cells along a perforation tract that may have developed at the time of a cardiac catheterization. There were no recurrences or metastases in any of the cases.
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PMID:A distinctive cardiovascular lesion resembling histiocytoid (epithelioid) hemangioma. Evidence suggesting mesothelial participation. 224 Mar 58

Malignant fibrous histiocytoma (MFH) developed spontaneously in subcutaneous tissue of the head of a 15-month-old male Fischer 344 rat. The tumor was serially transplanted into syngeneic rats up to the 45th generation and was designated MFH-MT. Light and electron microscopic examinations revealed that the original and serially transplanted tumors were composed of an admixture of fibroblast-like and histiocyte-like cells arranged in a storiform pattern. Neoplastic cells gave positive reactions for acid phosphatase, alkaline phosphatase, nonspecific esterase, alpha-1 antitrypsin and lysozyme. The tumors transplanted into the lungs and cutaneous tissue of the tail had a mixed histologic appearance of storiform, pleomorphic, myxoid and giant cell types. Moreover sclerosing hemangioma-like and osteosarcoma-like structures were also found. MFH-MT grew well in athymic nude mice showing neoplastic proliferation of pleomorphic cells strongly positive for alpha-1 antitrypsin. Development of MFH-MT was significantly retarded by the two antitumor drugs tested. The retarded tumors consisted predominantly of fibroblast-like cells and abundant collagenic fibers, whereas histiocytic cells decreased in number.
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PMID:Morphologic characteristics of a transplantable tumor derived from a spontaneous malignant fibrous histiocytoma in the rat. 254 24

Lung tissues from 13 patients with pulmonary sclerosing hemangioma were studied with antibody against surfactant apoprotein, Factor VIII-related antigen, or lysozyme. Surfactant apoprotein was detected in the cytoplasm of the cells lining cystic spaces and papillary projections. Surfactant apoprotein was found in a small number of stromal cells with abundant eosinophilic or clear cytoplasm and round to oval nuclei, which were characteristic in pulmonary sclerosing hemangioma as the main component. Surfactant apoprotein was also found in the stromal cells with small, dark nuclei similar to the lining cells. The lining and stromal cells contained neither Factor VIII-related antigen nor lysozyme. Our demonstration of surfactant apoprotein in these cells provides further support for the idea that pulmonary sclerosing hemangioma primarily consists of epithelial cells with differentiation to type II pneumocytes, as was deduced from ultrastructural investigations.
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PMID:Sclerosing hemangioma of the lung. Immunohistochemical characterization of its origin as related to surfactant apoprotein. 298 Nov 38

Two patients, a 62-year-old man and a 50-year-old woman, both with deep-seated atypical endothelial tumors within the wide concept of histiocytoid hemangioma, are reported. In case 1, the tumor involved the brachial vein, and, in case 2, a medium-sized vein of the anterior neck. In both cases the involved vein was occluded. Angiography in case 1 suggested a tumor that was enclosed by the same fibrous sheath, the conjunctiva vasorum, that enclosed the occluded vein and its concomitant artery. Both tumors were solid, without conspicuous vascular differentiation by light microscopy. Such differentiation, however, was evident from the electron-microscopic examination, which showed tumor cells with endothelial features forming primitive vascular structures. Positive lectin histochemistry (Ulex Europeus I) and positive immunohistochemistry for factor-VIII-related antigen, actin, and vimentin also gave strong support for the endothelial differentiation of the tumor cells. Immunohistochemical studies of markers for histiocytic (alpha 1-antitrypsin, ferritin, lysozyme), epithelial (cytokeratin, epithelial membrane antigen), and neuroectodermal (S-100 protein) and skeletal muscle (myoglobin) differentiation were negative. At follow-up, after 7 years and 2 years, respectively, there were no signs of local recurrence or metastasis.
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PMID:Atypical hemangioendothelioma of venous origin. A clinicopathologic, angiographic, immunohistochemical, and ultrastructural study of two endothelial tumors within the concept of histiocytoid hemangioma. 393 54

A 25-year-old Iranian man had undergone eye wall resection of a large von Hippel angioma to alleviate an exaggerated macular response, affording study by light and electron microscopy and immunohistochemistry before the obfuscatory effects of long-standing exudative retinal detachment, gliosis, or iatrogenic ablation supervened. We used this vantage point to assess the interrelation between the component endothelial cells, pericytes, and stromal foam cells. On the basis of staining with glial fibrillary acidic protein, factor VIII, the C3 fraction of complement, fibrinogen, and lysozyme, it is unlikely that stromal foam cells derive from glial precursors, but may represent degenerating cells, perhaps arising from a common vasoformative stem cell under hypoxic stress.
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PMID:von Hippel angiomatosis. A light, electron microscopic, and immunoperoxidase characterization. 635 9

This report presents the interesting case of a 50-year-old white man with an unusual benign tumor composed predominantly of a proliferation of atypical endothelial cells combined with a variable inflammatory response. This case represents an instance of the recently renamed entity "histiocytoid hemangioma" in which two organ systems are involved. Both skin and bone showed typical lesions. No physical connection jointed the separate lesions. The results of examination by light microscopy, electron microscopy, and immunoperoxidase examination for lysozyme and Factor VIII are reported. The significance of this case is that it supports the concept of classifying similar vascular lesions, despite varied organ system origin, into a single entity, the histiocytoid hemangioma.
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PMID:Histiocytoid hemangioma of the skin and scapula. A case report with electron microscopy and immunohistochemistry. 640 16

We describe histological, immunohistochemical and ultrastructural findings in a case of littoral cell angioma of the spleen in a 44 year old man. Beside phagocytosis and heavy haemosiderin deposits in the cytoplasm, a very characteristic and hitherto undescribed feature of the littoral cells was focal accumulations of eosinophilic globules 0.5-2 microns in size, which often entirely filled the cytoplasm of the tumour cells. Ultrastructurally the globules were composed of abundant cytoplasmic deposits of lysosomes and residual bodies. The globules most probably originate from the phagocytized red blood cells, lymphocytes and plasma cells. Immunohistochemically the tumour cells reacted positively with antibodies against factor VIII-related antigen, KiM1P, KP1 and lysozyme and negatively with antibodies against cytokeratins AE1-AE3, EMA and S-100 protein. Ultrastructurally the tumour cells often formed long cytoplasmic processes without external lamina and pinocytic vesicles. Scarce and poorly formed junctions between the tumour cells were seen. Very rarely cytoplasmic rod-shaped microtubulated bodies, often difficult to distinguish from heavy accumulations of lysosomes were observed.
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PMID:Littoral cell angioma of the spleen. A case report with ultrastructural and immunohistochemical observations. 751 May 15

This report describes a case of a malignant vascular tumor of the spleen with the morphologic, immunologic, and ultrastructural features observed in splenic sinus-lining cells (littoral cells). Histological examination showed a well-differentiated neoplasm forming ectatic blood channels with intraluminal papillary fronds. Tumor cells displayed malignant nuclear features and hemophagocytosis. Solid neoplastic areas with mitotic figures were present. Ultrastructurally, the tumor cells showed the concomitant presence of lysosomes and Weibel-Palade bodies. Immunohistochemically, the tumor cells were positive for both endothelial (Factor VIII-AG, CD34) and histiocytic markers (cathepsin D, lysozyme, alpha-1-antichimotrypsin). Our results indicate that angiosarcoma may originate from all the vascular compartments of the spleen, including red-pulp sinuses, and may have morphologic and immunophenotypic similarities to littoral cell angioma, a recently described benign vascular tumor of the spleen.
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PMID:Littoral cell angiosarcoma of the spleen. Case report with immunohistochemical and ultrastructural analysis. 757 79


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