Prenatal diagnosis of tracheal obstruction: possible association with maternal pertussis infection. (33/851)

A fetus with the sonographic appearance of echogenic and enlarged lungs and dilated trachea and bronchi, indicating laryngotracheal obstruction, is reported. Additionally, the fetus had ascites and subcutaneous edema and the amniotic fluid volume was reduced. Doppler flow investigation of the systemic venous circulation revealed signs of heart failure, and color Doppler visualized possible increased pulmonary flow. Following termination of pregnancy, autopsy confirmed the sonographic observations and revealed a hypoplastic thymus. During the present pregnancy the mother suffered from sustained cough, and serological tests revealed acute pertussis infection. Polymerase chain reaction investigation for Bordetella pertussis in the amniotic fluid was negative. The possibilities of pertussis toxins as noxious factors and of an atypical presentation of DiGeorge anomaly are discussed.  (+info)

Sinus histiocytosis with massive lymphadenopathy and malignant lymphoma involving the same lymph node: a report of four cases and review of the literature. (34/851)

Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease, is a disorder of unknown cause. Rarely, patients with SHML also have malignant lymphoma, usually involving anatomic sites different from those involved by SHML We report four patients in whom SHML and malignant lymphoma were identified in the same lymph node biopsy specimen. The SHML in each case was present as a small focus, less than 1 cm. Immunohistochemical studies showed that the abnormal histiocytes were positive for S-100 and negative for CD1a. The malignant lymphomas included two cases of follicular lymphoma and two cases of Hodgkin's disease, nodular lymphocyte predominant type. The presence of SHML in these patients did not impact clinical decisions, and there was no evidence of SHML elsewhere. Thus, the presence of focal SHML associated with malignant lymphoma in these cases was an incidental histologic finding that seems not to have had any clinical significance.  (+info)

Bartonella henselae infection as a cause of fever of unknown origin. (35/851)

Fourteen of 41 patients (34%) with a serological diagnosis of Bartonella henselae infection were found to have prolonged fever or fever of unknown origin, suggesting that generalized systemic B. henselae infection is not rare in immunocompetent healthy individuals.  (+info)

Hypothesis: differentiation of the human lymphoid system based on cell surface markers. (36/851)

Human lymphocytes can be separated into distinct populations based upon receptors on their cell surface. Thymus-derived (T-cell) lymphocytes can be identified by their ability to form rosetts with sheep erythrocytes (SRBC); bone marrow-derived (B-cell) lymphocytes bear characteristic surface markers for immunoglobulin, complement, and the Fc portion of IgG. Recently, populations of lymphocytes having either multiple markers or no detectable markers (null cells) have been observed. Based on studies of cell surface markers, a scheme is proposed that expands the known differentiation of the lymphod cell to include subpopulations which represent developmental stages. It is suggested that lymphocyte maturation involves alloantigenic changes in a circulating stem cell-drived nill cell, leading to a cell bearing markers for both T- and B-cells. It is from this latter cell that the classic T- and B-cells ultimately arise. Maturational defects which may explain the origin of primary lymphoproliferative diseases are discussed.  (+info)

Structural analysis of CTLA-4 function in vivo. (37/851)

CTLA-4-mediated inhibition of T cell activation may be accomplished by competition for ligands and/or by signals mediated through the intracellular domain. Studies have implicated Tyr201 in the cytoplasmic domain of CTLA-4 in regulating CTLA-4 signal transduction and intracellular trafficking. To investigate the mechanism of CTLA-4 function in vivo, transgenes encoding wild-type CTLA-4 (FL), a mutant lacking the cytoplasmic domain of CTLA-4 (DeltaCTLA-4 tail), or a CTLA-4 Tyr201 mutant (Y201V) were introduced into CTLA-4-deficient mice. CTLA-4-/- mice display an autoimmune lymphoproliferative disorder resulting in tissue destruction and early death. When either the FL or the Y201V transgene was bred into CTLA-4-/- animals, a complete rescue from lymphoproliferation and autoimmunity was observed. In contrast, CTLA-4-/- mice expressing the DeltaCTLA-4 tail transgene were long lived with no evidence of multiorgan lymphocytic infiltration, but exhibited lymphadenopathy and accumulated large numbers of activated T cells. Furthermore, these animals displayed a Th2-biased phenotype which conferred susceptibility to Leishmania infection. These results indicate that the inhibitory effect of CTLA-4 is mediated in part through the ability of the extracellular domain to compete for ligands. The cytoplasmic domain of CTLA-4, however, is required for complete inhibitory function of the receptor and for regulation of Th cell differentiation in vivo.  (+info)

Applications of flow cytometry to hematopoietic stem cell transplantation. (38/851)

Applications of flow cytometry to clinical and experimental hematopoietic stem cell transplantation (HSCT) are discussed in this review covering the following topics: diagnosis and classification of lymphohematologic disorders, quantitation of hematopoietic progenitors in the graft, lymphohematopoietic reconstitution following HSCT and animal models of human HSCT. At the end, the utilization of flow cytometry in clinical HSCT by Brazilian transplant centers is briefly reviewed.  (+info)

T and B cell populations in blood and lymph node in lymphoproliferative disease. (39/851)

Lymph node and peripheral blood lymphocytes were studied simultaneously for surface markers of T and B cells in 22 patients with lymphoproliferative diseases and 8 patients with non-neoplastic lymphadenopathy. This resulted in the classification of the malignancy from involved lymph nodes into 4 groups. Six patients had B cell lymphomata with normal or strong immunofluorescent staining for surface membrane immunoglobulin; 8 patients had B cell chronic lymphocytic leukaemia with pale staining for surface membrane immunoglobulin; 5 patients had T cell lymphomata and 3 patients were not definitely classifiable. In 6 out of 8 patients with B cell CLL, histopathology of lymph nodes showed infiltration with well differentiated lymphocytes and in all T cell lymphomata, the infiltrating cells were poorly differentiated. By the use of these markers, malignant lymphocytes were identified in the circulation in only 3 out of 6 patients with B cell lymphoma, in all patients with B cell CLL but in none of those with T cell lymphoma or unclassifiable lymphoma. Therefore a more conclusive characterization of the malignant lymphocyte in lymphoproliferative diseases must include an examination of involved lymph nodes.  (+info)

Membrane receptor sites for the identification of lymphoreticular cells in benign and malignant conditions. (40/851)

The cells of the lymphoreticular system are heterogeneous both morphologically and functionally. The bone marrow derived (B) lymphocyte can be identified by the presence of easily detectable surface immunoglobulin and a receptor for antigen-antibody-complement (EAC) complexes. Monocytes and histiocytes also bear a receptor for EAC and in addition possess a receptor for cytophilic antibody detected with red cell--IgG complexes (IgGEA). In man, thymus derived (T) lymphocytes form non-immune rosettes with sheep red blood cells (E). We have examined a number of malignant lymphoreticular populations for the presence of the EAC, EA, and E receptors on suspensions of cells and have adapted the technique to demonstrate the EAC and EA receptors on frozen tissue sections. Rosetted malignant cells can also be cytologically examined on Millipore filters. The malignant cells both in section and suspension from the spleens and lymph nodes of 6 patients with nodular lymphoma bound EAC but not IgGEA or E; by these criteria these malignant cells are of B lymphocytic origin. The malignant cells from the spleens of 2 patients with leukaemic reticuloendotheliosis and 1 patient with malignant histiocytosis could be classified as being of histiocytic origin by the selective binding of IgGEA. In 3 cases of diffuse lymphocytic lymphoma the malignant cells bound only E and are therefore of T lymphocytic origin. The application of these techniques to the classification of malignant lymphoma may lead to important theoretical and therapeutic advances.  (+info)