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Biomedical subjects

K Sheibani

Publications and source records attributed to K Sheibani.

104 records · Page 6Linked to original sources

Alternate chromogens as substitutes for benzidine for myeloperoxidase cytochemistry.

Myeloperoxidase staining methods for classification of leukemias have traditionally employed benzidine dihydrochloride as the chromogen. Recent Occupational Safety and Health Administration regulations have classified benzidine as a carcinogen, which severely restricts its use in the clinical laboratory. Twenty-two specimens from normal control subjects and leukemia patients, previously classified by FAB criteria, were stained with benzidine and two alternate chromogens, diaminobenzidine and Hanker-Yates reagent (p-phenylenediamine and pyrocatechol). In a random, blind fashion, three experienced observers scored the stains from each case according to quality of smear, degree of peroxidase positivity, tinctorial distinction between nucleus and cytoplasm, and overall acceptability of the stain. All three observers rated the substitute chromogens as adequate for routine myeloperoxidase cytochemical staining. It is concluded that either of the methods studied would have clinical utility and can substitute for benzidine as a myeloperoxidase chromogen.

Benzidines↗

Tissue immunomicroscopic evaluation of monoclonality of B-cell lymphomas: comparison with cell suspension studies.

A series of 80 tissues removed from patients having a variety of lymphoproliferative disorders were comparatively studied by cell suspension and cryostat frozen section tissue immunomicroscopic technics. Of 39 cases of non-Hodgkin's lymphomas studied by cell suspension, only 18 had surface immunoglobulins (SIg) markers consistent with monotypia (46%). Conversely, immunohistochemistry showed 18 cases (92%). Among the 18 cases in which there was no correlation between immunohistochemistry and cell suspension studies (46%), a variety of cytologic variants of non-Hodgkin's lymphomas was recognized, including nodular poorly differentiated lymphocytic lymphoma, nodular large cell lymphoma, and a soft tissue plasmacytoma. The lack of correlation between the two technics may be due to several different mechanisms, including the selective enrichment of the suspension by nonneoplastic cell populations resulting in a sampling artifact, the disappearance of endogenous SIg in large or plasmacytoid lymphocytes, and the presence of membrane-bound exogenous polyclonal SIG. Immunohistochemistry represents a reliable, simple technic for establishing monotypia in non-Hodgkin's B-cell lymphomas.

Antibodies, Neoplasm↗

Acute nonlymphocytic leukemia in patients receiving chemotherapy for nonmalignant diseases.

The occurrence of acute leukemia in patients receiving chemotherapeutic agents for malignant disease has been well established. Recent reports have suggested that chemotherapeutic drugs used to treat inflammatory conditions may have an oncogenic potential. From 1969 to 1977, 11 patients with a variety of collagen-vascular diseases who developed acute nonlymphocytic leukemia were seen at the Cleveland Clinic. Rheumatoid arthritis was the most common underlying disease, in addition to giant cell arteritis, polyarteritis nodosa, chronic glomerulonephritis, and scleroderma. All patients were treated with alkylating agents, and 10 of the 11 received multiple cytotoxic agents. According to the French-American-British classification there were six examples of M4 (myelomonocytic leukemia), with single examples of M1 (myeloblastic leukemia without maturation), M2 (myeloblastic leukemia with maturation), M5a (monocytic leukemia, poorly differentiated), M5b (monocytic leukemia, differentiated), and M6 (erythroleukemia). Cytogenetic studies were abnormal in five patients studied, showing varying degrees of aneuploidy. All patients died, and the mean duration of time from the diagnosis of leukemia to death was four and one-half months, with only one complete remission.

Arthritis, Rheumatoid↗

Immunohistochemistry of Warthin's tumor.

This study describes results of fresh-frozen immunohistochemistry applied to two typical Warthin's tumors. Polyclonal follicular center cell staining and an apparent reduction in the number of T-lymphocytes were found. These observations tend to support the concept that the lymphoid infiltrate in Warthin's tumor represents a reactive cellular proliferation.

Adenolymphoma↗

Malignant histiocytosis. Ultrastructural and immunocytochemical characterization.

The immunohistochemical and ultrastructural characteristics of involved lymph nodes from four patients with typical clinical and histopathologic features of malignant histiocytosis are reported. The neoplastic cells in all four cases had numerous irregular surface projections and pseudopodia, as well as lobulated or biolobed nuclei with macronucleoli. The cytoplasm contained many lysosomes, mitochondria, and polyribosomes, and displayed evidence of phagocytosis. Langerhans' granules were not identified. The ultrastructural features in the four cases were similar, effectively excluded an epithelial origin in each instance, and delineated morphological characteristics common to neoplastic macrophages. Intracytoplasmic muramidase (CM), an enzyme marker essentially restricted to cells of myeloid and true histiocytic origin, was identified with the unlabeled immunocytochemical technique and was strongly positive in neoplastic histiocytes at all stages of differentiation. Thus, fine structural features and the presence of CM are useful confirmatory studies in the diagnosis of malignant histiocytosis.

Cell Membrane↗

Giant cell myocarditis.

Giant cell myocarditis (GCM) as a distinct disease entity has been questioned. The superficial morphologic resemblance to cardiac sarcoidosis and incomplete histopathologic assessment of extracardiac organ systems in reported cases has suggested that GCM represents a predominant cardiac manifestation of generalized sarcoidosis. The morphologic and immunocytochemical features at autopsy of this rare disorder were seen in a 15-year-old boy. All other organs were free of granulomatous inflammation. Transition from normal myocardial fibers to giant cells was observed, without a limiting plasma membrane between the two different aspects of the fiber. Immunocytochemistry for cytoplasmic muramidase (CM) showed CM in neutrophils and tissue macrophages. Cytoplasmic muramidase was distinctly absent from the characteristic giant cells. The classification of GCM as a disease separate from generalized sarcoidosis may be justified.

Adolescent↗

Reliability of immunofluorescence of renal tissue obtained at autopsy.

A retrospective study of kidney tissues accessioned in the Department of Immunopathology was undertaken to determine the reliability of the direct immunofluorescence technic applied to necropsy tissues. Of 72 accessioned specimens, 27 were positive and showed a spectrum of immunomicroscopic patterns corresponding to different renal diseases. Only two patients whose specimens were negative by immunofluorescence had shown any clinical or light microscopic evidence of active glomerular disease. Periods from death to autopsy ranged from one to 20 hours. Positive fluorescence was found in tissues obtained as long as 20 hours after death. These findings suggest that immunofluorescent studies of autopsy-derived renal tissue yield acceptable results.

Acute Kidney Injury↗