PubMed Health⌕ Search

Biomedical subjects

Nora C J Sun

Publications and source records attributed to Nora C J Sun.

5 recordsLinked to original sources
PubMed2005

T-cell/histiocyte-rich large B-cell lymphoma displays a heterogeneity similar to diffuse large B-cell lymphoma: a clinicopathologic, immunohistochemical, and molecular study of 30 cases.

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL), a proliferating peripheral B-cell neoplasm, is a morphologic variant of diffuse large B-cell lymphoma (DLBCL), which may be confused with Hodgkin's lymphoma, non-Hodgkin's lymphoma, and reactive lymphadenopathies. Though more recent studies suggested that it might be a distinct clinicopathologic entity and/or a heterogeneous entity with derivation from germinal center B cells, its histogenetic derivation remains controversial. The authors analyzed 30 cases of THRLBCL to further characterize the origin of the neoplastic cells using immunohistochemical and molecular studies for expression of Bcl-6, CD10, and CD138, as well as rearrangements of IgH/bcl-2 genes on paraffin-embedded tissue. Half of the cases (15/30) showed Bcl-6 expression and five cases (19%) showed CD10 expression, but none had CD138 expression (0/20). Only three cases showed coexpression of both Bcl-6 and CD10. Molecular studies performed in 21 cases detected rearrangement of immunoglobulin heavy gene in 18 cases, with none having detectable Bcl-2 gene rearrangement. These data indicate that similar to DLBCL, the cell origin of neoplastic cells in THRLBCL is composed of a heterogeneous group of proliferating peripheral B cells, with only some cases originating from germinal center B cells and others derived from heterogeneous origins. Lack of Bcl-2 gene rearrangements seems to argue against a possible progression from preexisting follicular lymphoma. Thus, the normal counterpart of the neoplastic cells cannot at this time be the sole basis for the subclassification of THRLBCL.

Adolescent↗
PubMed2004

Changing pattern of AIDS: a bone marrow study.

We compared bone marrow findings in 2 groups of patients with AIDS during 2 different periods: group 1, n = 20; male/female ratio, 19/1; and group 2, n = 120; male/female ratio, 6/1. Bone marrow iron stores were decreased significantly in group 2 (P < .01), and the incidence of AIDS-related lymphomas was higher, with frequent bone marrow involvement. Two group 1 patients had Kaposi sarcoma, and a 21-month-old girl with transfusion-transmitted AIDS had Burkitt-like lymphoma. In group 2, 44 patients had a history of malignant neoplasms, including Kaposi sarcoma (10 cases), hematologic neoplasms (33 cases), and metastatic leiomyosarcoma (1 case). Of the 120 patients, 15 (12.5%) had bone marrow involvement by malignant neoplasms. The majority of the non-Hodgkin lymphomas were high-grade lymphomas. Patients with AIDS-related malignant neoplasms had higher CD4+ cell counts and viral loads than patients without malignant neoplasms (P < .01, P < .05, respectively). The finding of decreased iron stores in patients with AIDS might aid clinical management of their anemia. The increased incidence of malignant neoplasms, especially lymphomas, in recent years might be related to prolonged survival but with incomplete reconstitution of immune function after antiretroviral therapy.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Brain macrophage surface marker expression with HIV-1 infection and drug abuse: a preliminary study.

GOAL: To determine the heterogeneity of surface marker expression of macrophages in the temporal lobe of patients who died with AIDS who were also Drug Abusers (DAs). We studied the expression of macrophage surface markers CD11c, CD14, CD68, and HLA-DR and T cell surface markers CD4, and CD8. BACKGROUND: The macrophage is the prime locus for HIV-1-associated pathology, is the most frequently infected cell in the brain, and has the highest virus load compared to other cells. We previously described the heterogeneity of macrophage surface marker expression and performed morphometric analysis in peripheral nerves of patients who died from AIDS compared to HIV-1 negative individuals. We showed that the HIV-related neuropathy in AIDS is a multifocal process. It is similarly important to determine the expression of macrophage surface markers in brain. Temporal lobe tissue was selected for this preliminary study because we previously found elevated HIV-1 proviral DNA load and inflammatory processes in this neuroanatomic location for subjects who died with AIDS. There is a high prevalence of Drug Abuse in Miami, Florida, associated with AIDS that may interactively affect HIV-associated pathology. METHODS: Temporal lobe tissue was examined from 17 HIV-1-seropositive patients (4 with Drug Abuse and 13 without Drug Abuse) and 11 HIV-seronegative individuals (5 with Drug Abuse and 6 without Drug Abuse). Standard immunohistochemistry utilized alkaline phosphatase conjugate secondary antibody and fuchsin substrate. RESULTS: We found that HIV-1 infection and the interaction of HIV-1 infection and Drug Abuse produced changes in macrophage surface marker expression. Macrophage surface markers, CD11c, CD14, CD68, and HLA-DR, and T-cell marker CD4 were increased with statistical significance due to HIV-1 infection (all p < .001) whereas CD8 remained unchanged. Changes due to Drug Abuse alone were not significant. Interaction of Drug Abuse and HIV-infected individuals showed increased expression of CD68 (p = .011), HLA-DR (p = .001), CD4 (p = .027), and CD8 (p = .016). CONCLUSION: Drug Abuse and HIV-1 infection are factors that differentially and interactively result in multiple macrophages surface marker effects. In HIV-1 infected individuals, Drug Abuse stimulates surface marker expression. Since brain macrophage surface makers do not change uniformly as a result of Drug Abuse and HIV infection, these cells may be heterogeneous and contain sub-types (sub-sets). It remains to be determined which macrophage sub-types may be most pathognomic for pathology.

AIDS Dementia Complex↗