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Biomedical subjects

R B Mann

Publications and source records attributed to R B Mann.

88 records · Page 5Linked to original sources
PubMed1980

Non-Hodgkin's lymphomas in leukemic phase: clinicopathologic correlations.

A leukemic phase occurred in 30 (14 percent) of 214 patients with non-Hodgkin's lymphoma. To determine the significance of peripheral blood involvement in each type of NHL, patients were subdivided according to a modified Rappaport classification. Each histologic subtype presented a homogeneous clinical picture which differed from that seen in other histologic subtypes. Of particular note was the recognition of two distinctive cytologic and clinical subtypes within the category of nodular lymphoma, poorly differentiated lymphocytic lymphoma (NPDL). In one subtype, the predominant cells had cytologic features akin to those of lymphoblasts. In these cases, although the interval to peripheral blood involvement was variable, the median leukemic survival was only two months. In contrast in conventional NPDL the median leukemic survival was 43+ months, and peripheral blood involvement did not appear to exert an independent effect on prognosis. In diffuse large cell lymphomas the median leukemic survival was 0.5 months, with peripheral blood involvement appearing as a terminal event associated with unresponsive disease in multiple sites. The recognition of adult lymphoblastic lymphoma as a clinicopathologic entity with a high risk of leukemic conversion, 100 percent in this study, is also confirmed.

Adolescent↗
PubMed1978

Immunologic aspects and pathology of the malignant lymphomas.

Malignant lymphomas have traditionally been classified on solely morphologic grounds. With new immunologic and cytochemical techniques, it has been possible to characterize normal cells of the T-lymphocytic, B-lymphocytic, and monocyte-macrophage systems. Application of these methodologies to malignant lymphomas has established their nature as neoplasmas of the immune system. Within the B-lymphocytic system it is possible to identify subpopulations responsible for Burkitt's tumor, follicular (nodular) lymphomas, lymphocytic lymphomas of intermediate differentiation and well differentiated lymphocytic lymphomas. The T-lymphocytic system includes lymphoblastic lymphomas, mycosis fungoides, and Sezary's syndrome. Large cell lymphomas are diverse but the majority are tumors of transformed lymphocytes, usually of the B-lymphocytic system. The precise nature of the neoplastic cells of Hodgkin's disease, i.e., Reed-Sternberg cells and their mononuclear counterparts, has not yet been established. Despite previous suggestions of a B-lymphocytic or T-lymphocytic origin, recent studies utilizing in vivo cultivation have strongly suggested derivation from the monocyte-macrophage system.

Adolescent↗
PubMed1978

Immunoblastic sarcoma of the central nervous system in a patient with lymphomatoid granulomatosis.

A 26-year-old man with lymphomatoid granulomatosis (LYG) was found at postmortem examination to have an immunoblastic sarcoma involving the central nervous system. Residual evidence of LYG was present only in the lungs at autopsy. Studies for intracellular immunoglobulin utilizing the immunoperoxidase technique showed a marked polyclonal reaction in sections of lymph nodes and occasional cells in the cellular central nervous system tumor that stained for intracellular immunoglobulins (IgG, IgM and both kappa and lambda). This case may represent another example of immunoblastic sarcoma occurring in the presence of an abnormal immune state or proliferation.

Adult↗
PubMed1976

Non-endemic Burkitt's lymphoma. A B-cell tumor related to germinal centers.

To investigate the nature of non-endemic Burkitt's lymphoma, we examined neoplastic cells from eight American patients for receptors for sheep erythrocytes (E), complement (EAC), and Fc fragment of lgG (igGEA), and for surface immunoglobulins (Slg) and hydrolytic enzymes. In addition, we reviewed 47 biopsies and 17 autopsies from American patients to ascertain patterns of involvement by tumor in lymph nodes, spleens and Peyer's patches. Neoplastic cells in all cases studies bore monoclonal surface immunoglobulins of the igM class. Receptors for EAC and igGEA were identified on a minority of the cells. Little or no hydrolytic enzyme activity was demonstrable. These results indicate that, like Burkitt's lymphoma in Africans, this histologically identical tumor in American patients consists of B lymphocytes. In 10 biopsies and two autopsies, germinal centers were selectively involved by tumor, suggesting that these neoplastic cells may be related to some B lymphocytes of normal germinal centers.

Africa↗
PubMed1976

Unusual manifestation of tuberculosis: TE fistula.

Fistulas between the tracheobronchial tree and the esophagus (TE fistula) caused by tuberculosis are rare; usually they are associated with readily apparent pulmonary and/or mediastinal infection, and require surgical management. The patient we describe presented with a TE fistula as the only manifestation of active tuberculosis. This case represents the first report of successful nonsurgical treatment of tuberculous TE fistulas.

Adult↗
PubMed1975

Immunologic and morphologic studies of T cell lymphoma.

Thymic-independent (B) lymphocytes, thymic-independent (T) lymphocytes and histiocytes may be distinguished by the presence of certain surface markers. In addition B and T lymphocytes have been reported to show distinctive surface architecture by scanning electron microscopy. Neoplastic cells from a lymph node and cerebrospinal fluid of a patient with a diffuse malignant lymphoma of the poorly differentiated lymphocytic type were examined in frozen sections and cell suspensions for the presence of surface immunoglobulin and the antigen-antibody-complement (IgMEAC) receptor of B lymphocytes, the presence of the cytophilic antibody (IgGEA) receptor of histiocytes and the ability to form nonimmune rosettes with sheep red blood cells (E) characteristic of T lymphocytes. Cells from the lymph node were also studied by scanning electron microscopy. The majority of neoplastic cells from the lymph node and cerebrospinal fluid formed rosettes with E, but lacked surface immunoglobulin and failed to bind IgMEAC or IgGEA. By scanning electron microscopy the neoplastic cells, although larger in diameter, showed surface architecture similar to normal lymphocytes with a varying number of surface microvilli. These studies suggest that the malignant cells of this lymphoma are of thymic type.

Adolescent↗
PubMed1975

Interaction of rifampin and warfarin.

A 72-year-old man who had been taking rifampin daily for several months was concurrently administered warfarin daily for ten weeks. During this period, the prothrombin time (PT) rose remarkably little as the dosage of warfarin was increased. With difficulty, satisfactory anticoagulation was achieved by giving warfarin 20 mg daily. On discontinuation of rifampin therapy, the PT increased significantly, and subsequent stabilization of the PT within therapeutic range required treatment with warfarin 7.5 mg daily.

Aged↗