Immunohistochemical demonstration of acid phosphatase isoenzyme 5 (tartrate-resistant) in paraffin sections of hairy cell leukemia and other hematologic disorders

The demonstration of tartrate-resistant acid phosphatase (TRAP) activity has long been a cornerstone in the diagnosis of hairy cell leukemia (HCL). Recently a monoclonal antibody to this enzyme has been developed that can be used in an immunoperoxidase method on paraffin-embedded tissues. By using a peroxidase-labeled streptavidin biotin method, paraffin sections of B5 and formalin-fixed tissue from 86 cases of HCL (41 bone marrow, 36 spleen, 9 liver) were stained with the antibody to TRAP and compared against staining for CD20 (L26) and DBA.44 (DAKO, Carpinteria, Calif). In addition, 193 specimens (127 bone marrow, 42 lymph node, 19 spleen, 5 other) from a variety of neoplastic and nonneoplastic hematologic conditions were stained using the monoclonal antibody to TRAP. For comparison, these cases were also stained with DBA.44. In the cases of HCL, 80 of 86 specimens were immunoreactive for TRAP. While the antibody to TRAP generally stained less than 50% of the hairy cells, CD20 and DBA.44 stained 90% and 50% to 60% of hairy cells, respectively. Two of three cases of marginal zone lymphoma showed weak immunoreactivity to the TRAP antibody. Two specimens from a patient with Gaucher's disease and 8 of 13 cases of mastocytosis also showed positivity to the TRAP antibody in the macrophages and mast cells, respectively. In contrast, staining for DBA.44 was positive in 3 of 9 cases of B-cell large cell lymphoma, 1 of 4 cases of mantle cell lymphoma, and in the paraimmunoblasts of 1 of 7 cases of small lymphocytic lymphoma. Only HCL was TRAP and DBA.44 positive. This antibody to TRAP is a useful addition to the diagnosis of HCL but should be used in conjunction with CD20 and DBA.44. The use of this antibody to determine minimal residual disease after chemotherapy was not addressed.     

Terra firma forme dermatosis

Despite previous unsatisfactory results with inverted pulmonary homografts in mitral valve replacement, we have rekindled our interest in this technique by the use of a pulmonary autograft with the fully flexible 'top hat' type of mounting. The surgical technique and the clinical feasibility of the operation are presented.     

Brief communication: effects of diagnostic irradiation during pregnancy on head circumference at birth

A historical cohort study was carried out to evaluate the effects in utero medical ionizing radiation on head circumference at birth. The nature of medical practice in Rochester, Minnesota, and the Mayo Clinic medical records linkage system enabled us to provide accurate estimates of medical radiation absorbed dose in 9,793 pregnancies of 2,980 women pregnant in Rochester between 1917 through 1973. Data were controlled for sex of the fetus, duration of pregnancy and congenital head abnormalities. It was found that medical ionizing radiation in the second and third trimesters of more than 300 mrad were related to significantly decreased head circumference. There was no significant effect of radiation exposure in the first trimester or periconceptional period. Medical ionizing radiation in the second and third trimesters of more than 300 mrad is related to a significant yet minimal, decreasing head circumference at birth. Maximum effects were seen during the midgestational and second trimester periods.     

A comparison of risk assessment of single and combination manual handling tasks: 1. maximum acceptable weight measures

Many manual handling activities involve combinations of pull, lift, carry, lower and push, yet few studies have investigated how to assess the risk of such combination tasks. Most recommendations assume that a combination task can be split into its components for assessment. The aim of this study was to compare the risks assessed in single manual handling tasks with those in combination tasks. Nine male and nine female students participated in a study to determine Maximum Acceptable Weights (MAWs) in single and combination tasks at different frequencies (1 min-1 and 3 min-1 for combination tasks and 3 min-1 and 6 min-1 for single tasks) and heights (floor, knuckle, shoulder). Combination tasks consisted of one each of the single tasks (pull, lift, carry, lower and push). The MAW of each combination task was compared to the MAWs of the single tasks of which it was composed using repeated measures analysis of variance with specified contrasts. In at least one of the 12 comparisons each single task MAW was found to be different from its related combination task MAW. It was concluded that the current use of single task MAWs to estimate the risk in combination tasks was unacceptable. Prediction models for combination task MAWs based on single tasks MAWs were also developed, using step-wise regression. Although coefficients of determination of around 0.8 were achieved it was argued that owing to their situation-specific nature the prediction of combination task risk using single task MAWs was likely to result in unacceptable risk errors.