High dose chemotherapy with busulfan, cyclophosphamide, and etoposide as conditioning regimen for allogeneic bone marrow transplantation for patients with acute myeloid leukemia in first complete remission.

We explored the combination of busulfan/cyclophosphamide/etoposide as conditioning regimen prior to bone marrow transplantation in 31 patients with acute myeloid leukemia (AML) in first complete remission. The preparative regimen consisted of 16 mg/kg busulfan, 30-60 mg/kg VP-16, and 120 mg/kg cyclophosphamide. With a median follow-up of 30.5 months (range, 5-60 months), 25 patients are alive in continuous complete remission. Estimated disease-free survival at 5 years is 80.5%. Death was due to transplant-related toxicity (graft-versus-host disease and cytomegalovirus infection, graft-versus-host disease and pneumonia, sepsis and mucositis, respectively). None of the patients have relapsed. As demonstrated by the results of this analysis, the conditioning regimen busulfan/cyclophosphamide/etoposide is effective and well tolerated in patients with AML in first complete remission. Main nonhematological toxicities were mucositis and hepatotoxicity. The low mortality and relapse rate appears to justify allogeneic bone marrow transplantation for patients with AML in first complete remission who have an HLA-identical donor. Whether this regimen offers a substantial improvement in disease-free and overall survival over presently used regimens warrants further investigation.

Monoclonal antibody against a sperm antigen Mr 95,000 inhibits attachment of human spermatozoa to the zona pellucida.

A murine monoclonal antibody raised against hamster spermatozoa was found to cross-react with human spermatozoa. By immunofluorescence, the antigen was visualized over the equatorial segment of human sperm heads. In the presence of antibody, sperm binding to the zona pellucida of salt-stored human oocytes was significantly inhibited (P less than or equal to 0.005) compared with other antibodies or control preparations. Using SDS-PAGE of whole spermatozoa and membrane preparations followed by Western blot analysis, the antigen was identified as a determinant with a relative molecular weight of 95,000.

An estimate of the economic effects of cattle tick (Boophilus microplus) infestation on Queensland dairy farms.

OBJECTIVE: To establish the cost to the Queensland dairy industry of cattle tick infestation and its control, excluding the costs incurred from control measures directed specifically at tick fever and morbidity and mortality arising from tick fever. STUDY DESIGN: Economic models are described that have been based on empirical data relating to liveweight and milk yield loss, and on a survey of control practices and tick infestation. The first two models were designed to estimate costs of control and losses resulting from tick infestation on a single dairy farm. The third model developed estimates of the cost of tick infestation for each of four regions within the tick-infested area of Queensland. RESULTS: The overall cost to the Queensland dairy industry of the cattle tick (excluding the costs associated specifically with tick fever) and based on 1998 management practices, was $4,096,000 per annum. About 49% of this cost was related to the costs of control and 51% to losses in production. CONCLUSION: Cattle tick infestation represents a significant impost on dairy producers in Queensland, and although the actual cost will change as deregulation results in economic changes in the industry, infestations of ticks will continue to be expensive to control.

In vitro response of chondrocytes to mechanical loading. The effect of short term mechanical tension.

Chick epiphyseal chondrocytes were grown in high density cultures for 14 days, after which the cell layers were placed in a cyclical stretching apparatus and subjected to a strain of 5.5% at a frequency of 0.2 Hz. There was a 1.4- and 1.7-fold increase in the incorporation of 35SO4 and 14C-glucosamine, respectively, into glycosaminoglycans in cultures subjected to mechanical loading for 24 h. No significant change was observed in the hydrodynamic size of the proteoglycans synthesized by chondrocytes subjected to mechanical loading. In this time period there was no increase in 3H-glycine incorporation into acid-insoluble protein, but there was a 2.4-fold increase of 3H-thymidine into DNA in cultures subjected to tensional strain. Concomitant with these changes, the cellular levels of cyclic AMP increased 2.2 times in the mechanically loaded cultures. This is discussed as a possible mechanism whereby chondrocytes respond to mechanical stimuli.