AIDS-associated secondary lymphoma of bone: a case report with review of the literature.

Although musculoskeletal lesions are not reported as commonly as pulmonary or central nervous system abnormalities in human immunodeficiency virus (HIV)-positive individuals, a wide variety of osseous and soft-tissue changes are seen in these patients. We describe the case of a 35-year-old injection drug user with acquired immune deficiency syndrome (AIDS) who presented with diffuse adenopathy, lower extremity pain and swelling, subcutaneous nodules, and constitutional symptoms. Radiographic images showed bilateral lytic lesions of the tibia and accompanying soft-tissue masses. Biopsy of the bone and soft-tissue abnormalities established a diagnosis of Burkitt's-like non-Hodgkin's lymphoma (NHL). By recognizing the heterogeneity of AIDS-associated NHL presentations, and the potential clinical overlap between malignancy, infection, and other rheumatologic abnormalities, physicians may obtain appropriate diagnostic studies and offer treatment recommendations.

Adult acute leukemia: hand mirror cell variant.

Two patients with numerous hand mirror cells in the bone marrow were investigated by morphologic, cytochemical, immunohistochemical, flow cytometric, cytogenetic, and gene rearrangement analysis. Both demonstrated a mixed immunophenotype with expression of myeloid and T-lymphoid features. Interestingly, both strongly expressed CD2 (adhesion molecule) and CD7. Review of the literature uncovered additional cases of acute mixed leukemia--hand mirror variant with strong expression of CD2, CD7, and CDIIb, suggesting a unique subset. Under normal physiologic conditions lymphoid cells and monocytes assume a hand mirror configuration when adhesion molecules (i.e., CD2, CDIIb) are triggered by their corresponding ligands. Evidently not all acute leukemias with surface adhesion molecules form hand mirrors, which suggests an additional stimulatory event. The presence of adhesion molecules on these activated cells is important to homing, trafficking, spread of the malignant cells, clinical course, prognosis, and treatment. Therefore all HMC cases require detailed analysis to ensure accurate diagnosis. In-depth evaluation of such cases should give new insights into clinical presentation, prognosis, and treatment of these unusual cases.

Adsorption of Hageman factor (factor XII) and other human plasma proteins to biomedical polymers.

Protein adsorption to surfaces occurs whenever blood comes into contact with biomaterials, prosthetic devices, and artificial organs. The plasma protein Hageman factor (factor XII) present at the interface between blood and foreign surfaces can be qualitatively and quantitatively detected after in vitro perfusion of anticoagulated human blood through important biomedical polymers. We have determined protein adsorption by a modified radioimmunoassay and by scanning electron microscopy using immunogold labeling techniques. The materials used included vascular graft materials (Dacron and expanded polytetrafluoroethylene) and the National Heart, Lung, and Blood Institute-Devices and Technology Branch reference materials polydimethylsiloxane, polyethylene, and silicone rubber. Factor VIII-von Willebrand factor, another trace plasma protein, and other plasma proteins such as fibrinogen, immunoglobulin G, albumin, fibronectin, and hemoglobin were also detected at the blood-contacting surface. At physiologic flow rates, the adsorption of these proteins from the circulating blood to the surface of these materials appears to be a function of time, with certain materials, as well as of the physical and chemical characteristics of the material surface. Hageman factor adsorption to surfaces, quantified under static conditions, occurs at nanogram concentrations. These data suggest that trace proteins, such as those important in the activation of the coagulation cascade, can significantly affect the blood compatibility or thrombogenicity of an implanted device.

Morphologic characteristics of adsorbed human plasma proteins on vascular grafts and biomaterials.

Protein adsorption on the surfaces of clinically significant prosthetic vascular graft materials from human whole blood was independent of plasma concentration as determined morphologically by use of immunogold labels. Some proteins, such as fibrinogen, adsorbed in a multilayer pattern on expanded polytetrafluoroethylene and had a preference for particular surface features of the polymer. Other proteins, such as Hageman factor (factor XII), showed diffuse adsorption patterns. Physiologically significant proteins that have not been well studied, such as immunoglobulin G and factor VIII, adsorbed readily to the surface of expanded polytetrafluoroethylene. This finding may be significant since adsorbed proteins may activate coagulation mechanisms and immunologic responses, including platelet and monocyte adhesion and activation. Any human blood protein for which an antibody has been developed can be studied by use of this technique.

Breast cancer in a male-to-female transsexual. A case report.

The clinicopathological findings in a patient who developed breast carcinoma ten years after male-to-female sexual reassignment are reported. Only two other cases of transsexual men with breast carcinoma have been reported previously. All three patients received oral estrogens for prolonged periods to maintain secondary female characteristics. The controversies relating to hormonal influences in the etiology of breast cancer in men are discussed herein.

Turbidimetric determination of transthyretin (prealbumin) with a centrifugal analyzer.

We describe a simple, rapid turbidimetric method for measuring transthyretin in human serum by use of a centrifugal analyzer (Cobas-Bio) and commercially available antiserum. The immunoturbidimetric reaction is monitored at 340 nm for 180 s, and the changes in absorbance after the antiserum is added are used to prepare a stable standard curve. The range of measurement is 10 to 520 mg/L. The CV for between-day precision was less than 5.0% for normal and low controls. Bilirubin up to 310 mumol/L and hemoglobin up to 225 mumol/L did not interfere, but triglycerides greater than 2.3 mmol/L falsely depress the results. The normal reference interval for adults, derived from data on subjects 20 to 65 years old (both sexes), is 193 to 376 mg/L. Concentrations are lower in children (67-302 mg/L) and in adults 65 or more years old (113-292 mg/L).