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Biomedical subjects

N C Sun

Publications and source records attributed to N C Sun.

At least 55 records · Page 3Linked to original sources

Demonstration of human immunodeficiency virus in renal epithelium in HIV-associated nephropathy.

HIV-associated nephropathy (HIVAN) is a renal disease characterized clinically by heavy proteinuria and renal failure and morphologically by severe and rapidly evolving focal and segmental glomerulosclerosis, tubular necrosis, interstitial edema, and ultrastructural cellular inclusions. In an attempt to elucidate its pathogenesis, we evaluated the role of direct viral (HIV) infection of renal epithelium with the use of a cDNA probe for viral nucleic acid and an immunoperoxidase-labeled antibody to p24 core protein. In 10 of 11 kidneys with HIVAN, nucleic acid was localized to glomerular and tubular epithelium, while only 2 of 4 kidneys from HIV-infected patients with immune complex glomerulonephritis were similarly affected, but with considerably less cellular involvement. Kidneys from patients with acquired immune deficiency syndrome but without renal disease had only rare cellular positivity. In all instances, the cDNA probe was more sensitive than anti-p24 immunoperoxidase. These data suggest a role for direct HIV infection of renal epithelial cells in the initiation and/or progression of HIV-associated nephropathy.

Acquired Immunodeficiency Syndrome↗

Bone marrow findings in immunodeficiency syndromes.

We have summarized the findings in selected congenital and acquired immunodeficiency disorders that frequently display blood and bone marrow abnormalities. Many other immunodeficiency syndromes were not discussed, as bone marrow abnormalities are infrequently seen in them. Examination of the bone marrow is not usually critical for diagnosing most immunodeficiency disorders. However, it may be diagnostic in the evaluation of fever of unknown origin, to rule out other causes of peripheral cytopenias, and to screen for virus-associated malignancies frequently seen in immune-deficient patients (for example, B cell lymphoma, Kaposi's sarcoma). Examination of the bone marrow is critical in the diagnosis of the virus-associated hemophagocytic syndrome and is often important in evaluating patients with the acquired immunodeficiency syndromes who display hematologic disturbances, such as those being treated with AZT, or those who might have opportunistic infections or malignant neoplasms.

Bone Marrow↗

Plasma cell tumors of the head and neck.

This communication discusses seven cases of plasma cell tumors isolated to the head and neck and reviews the pertinent literature. Five of the cases presented were located in the nasal passages and the paranasal sinuses, one in the temporal bone and one in the mandible. Because these neoplasms may signal the presence of multiple myeloma, full evaluation is required to exclude disseminated disease. Thereafter, the treatment of choice is high-dose radiotherapy with life-long follow-up. Radiographs and paraprotein levels may be used to assess tumor control or dissemination. Should new lytic lesions occur, or an elevation in paraprotein levels be noted, consideration should be given to further irradiation or systemic chemotherapy. Surgery is reserved exclusively for diagnostic purposes or when severe functional disability intervenes.

Adult↗

Simultaneous occurrence of Hodgkin's disease and Kaposi's sarcoma in a patient with the acquired immune deficiency syndrome.

Kaposi's sarcoma and Hodgkin's disease have each been associated with abnormalities in T lymphocyte function and occur with increased frequency in the immunosuppressed host. Although the association of Kaposi's sarcoma with lymphoreticular disorders has long been recognized, only sporadic cases of Hodgkin's disease have been described in patients with the acquired immune deficiency syndrome (AIDS) in contrast to the frequent occurrence of non-Hodgkin's lymphoma in these patients. The simultaneous occurrence of Kaposi's sarcoma and Hodgkin's disease in the same lymph node is described in a patient with AIDS. This case suggests an association of AIDS with both Kaposi's sarcoma and malignant lymphomas and raises the question of a common pathogenetic mechanism.

Acquired Immunodeficiency Syndrome↗

Multicentric angiofollicular lymph node hyperplasia (Castleman's disease) followed by Kaposi's sarcoma in two homosexual males with the acquired immunodeficiency syndrome (AIDS).

Two homosexual men with the acquired immunodeficiency syndrome (AIDS) who developed a multicentric variant of angiofollicular lymph node hyperplasia (AFLNH) (Castleman's disease) and Kaposi's sarcoma are reported. Both had diffuse adenopathy, splenomegaly, and a systemic inflammatory state. Both had an absolute increase in Leu 1+ lymphocytes, which was associated with markedly decreased Leu 3+ lymphocytes, markedly increased Leu-2+ lymphocytes, and a very low Leu 3/2 ratio. The lymphocytes of both patients had a normal blastogenic response to PHA. The lymphocytes of patient 1 had a poor response to autologous or allogenic cells in the mixed lymphocyte culture reaction. AFLNH represents another lymphoreticular complication of AIDS. Given the interrelationships between AFLNH, the development of Kaposi's sarcoma, and the aggressive clinical course seen in our two patients and those in the literature, the aggressive use of lymph node biopsy may be an important prognostic tool for the patient with the acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome↗

Immunohistochemical localization of carcinoembryonic antigen (CEA), CEA-S, and nonspecific cross-reacting antigen (NCA) in carcinomas of lung.

Antisera to carcinoembryonic antigen (CEA), to a physicochemical subset of CEA, namely CEA-S, and to nonspecific cross-reacting antigen (NCA) were used for the immunohistochemical localization of these antigens in human bronchogenic carcinomas using a triple layer immunoperoxidase technique. The study is based on an analysis of tumors from 130 patients. CEA, CEA-S, and NCA were all identified in the membrane and/or cytoplasm of neoplastic cells, and a good correlation between the antigens was observed in a majority of tumors. The presence or absence of these tumor-associated glycoproteins appeared to be correlated with the histologic type of the tumors, especially in small cell anaplastic carcinoma and adenocarcinoma, and the degree of histologic differentiation of adenocarcinomas correlated positively with these tumor-associated antigens. Data from this group of patients suggest that analysis of tissue CEA at the time of biopsy or surgical resection may facilitate a more objective interpretation of serial plasma CEA assays.

Adenocarcinoma↗

Changes of plasminogen activator in human uterine tissue induced by intrauterine contraceptive devices.

Potassium thiocyanate-extractable uterine plasminogen activator activity was determined to be highest in the endometrium surrounding intrauterine devices (IUDs). Such activity was significantly higher than that encountered in control endometrium or in the endometrium remote to IUDs. As in control cases, extracted endometrial activity fluctuated during the intermenstrual ovarian cycle. It was highest in the pre- or periovulation part of the cycle, and it rose again prior to menstruation. These peaks of activity seem to correspond to times in the cycle when metrorrhagia and abnormal menstruation are usually encountered. Possible implications of the myometrial and endometrial patterns of plasminogen activator in control and IUD-exposed uterine tissue are discussed.

Endometrium↗

Cutaneous lesions in hairy-cell leukemia. Case report and review of the literature.

A patient is described in whom cutaneous lesions were the initial manifestation of hairy-cell leukemia. Touch preparations made immediately on removal of a 3-mm punch biopsy specimen of the cutaneous lesions revealed acid-phosphatase positive, tartrate-resistant staining in the leukemic cells, and helped to establish the diagnosis. Specific eruptions occur in approximately 7% of patients with hairy-cell leukemia, appearing grossly as disseminated, erythematous maculopapules, with a perivascular mononuclear leukemic cell infiltrate seen microscopically. A review of the English literature indicates that cutaneous manifestations are not generally recognized as a diagnostic source in individuals with hairy-cell leukemia, and biopsy is seldom undertaken.

Acid Phosphatase↗

In vitro transformation of Syrian hamster epidermal cells by N-methyl-N'-nitro-N-nitrosoguanidine.

The selection of Syrian hamster epidermal cells which do not terminally differentiate has provided a quantitative focus assay for in vitro chemical transformation. One-day-old Syrian hamster epidermal cells plated at 5 x 10(6)/100-mm dish were treated for 5 hr with various concentrations of N-methyl-N'-nitro-N-nitrosoguanidine. After 4 weeks, the normal epidermal cells began to terminally differentiate to keratinized squamous cells and died, but transformed epidermal colonies grew to higher cells densities and appeared as darker areas against a lightly stained normal cell background. Transformed epidermal foci were isolated and subcultured for at least 15 passages, whereas normal epidermal cells could not be subcultured under the same conditions. The transformed cells assumed the typical cobblestone-like morphology of epithelial cells, retained desmosomes and tonofilaments, and were able to use citrulline in place of arginine. Argininosuccinate synthetase (EC 6.3.4.5) activity was significantly higher in the epidermal cells than in fibroblasts. The injection of 5 x 10(6) cells of two transformed epidermal cell lines into athymic nude mice resulted in the formation of tumors which were identified as keratinizing squamous carcinomas.

Animals↗

Hand-mirror cell leukemia. Report of nine cases and a review of the literature.

In order to determine the significance of 40% or more leukemic cells in hand-mirror configuration in the bone marrow (hand-mirror cell leukemia), eight of 34 cases of acute lymphoblastic leukemia and one of 17 cases of acute myeloblastic leukemia were collected from a six-year period. Five of the eight patients who had acute lymphoblastic leukemia were children; the remaining patients were less than 40 years of age. Females outnumbered males two to one. Cytochemical and electron-microscopic studies were performed for three cases. The clinical presentations were similar to those of patients without the hand-mirror cell variant, except for a high incidence of central nervous system relapses (over 50% of patients) despite prophylaxis. When compared with patients with acute leukemia in equivalent age and morphologic categories, adults with the hand-mirror cell variant had a similar, but not better, prognosis, while children with the variant had a poorer prognosis. Additional studies must be performed to determine whether the hand-mirror cell variant warrants separation from other forms of acute leukemia.

Adult↗

Immunoperoxidase staining of cytoplasmic immunoglobulins. A diagnostic aid in distinguishing cutaneous reactive lymphoid hyperplasia from malignant lymphoma.

A method for staining cytoplasmic immunoglobulins utilizing an immunoperoxidase technic on paraffin-embedded tissue was used to examine two cutaneous lesions. On routine hematoxylin-eosin staining, one lesion exhibited what appeared to be a mixed population of mature cell types and was therefore interpreted as reactive lymphoid hyperplasia, whereas the other lesion showed a uniform population of immature cells and was interpreted as a malignant lymphoma. Immunoperoxidase staining supported these interpretations since the reactive lesion showed polyclonal IgG lambda and kappa staining, and the malignant lymphoma monoclonal staining with IgG lambda. In selected material, immunoperoxidase staining can distinguish a truly mixed population of cell types (probably benign) from a monoclonal population of cells exhibiting either uniform or mixed morphologic configurations associated with B lymphocyte transformation (probably malignant).

Aged↗

Granulocytic sarcoma of the skin.

A patient with aleukemic leukemia of the acute granulocytic type, who initially had granulocytic sarcoma of the skin, is described. The skin contained focal infiltrates of pleomorphic mononuclear cells that were identified as granulocytes by demonstration of intracytoplasmic naphthol-ASD-chloroacetate esterase and lysozyme.

Aged↗

Lymphoplasmacytic myeloma: an immunological, immunohistochemical and electron microscopic study.

An unusual case of a light chain plasma cell myeloma is described. The disease was initially characterized by a diffuse lymphoplasmacytic bone marrow involvement, but subsequently developed widespread extramedullary metastases with anaplastic tumors in the skin which histologically resembled a "histiocytic lymphoma." Electron microscopic examination, in vitro protein synthesis of bone marrow lymphoidal cells, chemical and immunochemical studies of serum and urine proteins, and intracellular immunoglobulin study by the immunoperoxidase technique on the skin biopsy and postmortem tumor tissue demonstrated evidence for lambda light chain synthesis and secretion. These findings provide further support to the notion that the wide spectrum of diverse morphologic patterns seen in lymphoplasmacytic disorders originates from the same progenitor B-lymphoid cell. Distinguishing anaplastic variant of plasma cell myeloma from other undifferentiated neoplasms offers a challenge.

Bone Marrow↗