UV-microbeam irradiations of the mitotic spindle: spindle forces and structural analysis of lesions.

Mitotic PtK1 spindles were UV irradiated (285 nm) during metaphase and anaphase between the chromosomes and the pole. The irradiation, a rectangle measuring 1.4 x 5 microns parallel to the metaphase plate, severed between 90 and 100% of spindle microtubules (MTs) in the irradiated region.

UV microbeam irradiations of the mitotic spindle. II. Spindle fiber dynamics and force production.

Metaphase and anaphase spindles in cultured newt and PtK1 cells were irradiated with a UV microbeam (285 nM), creating areas of reduced birefringence (ARBs) in 3 s that selectively either severed a few fibers or cut across the half spindle. In either case, the birefringence at the polewards edge of the ARB rapidly faded polewards, while it remained fairly constant at the other, kinetochore edge. Shorter astral fibers, however, remained present in the enlarged ARB; presumably these had not been cut by the irradiation.

Identification of cultured, human, malignant, prostatic epithelial cells.

Identification of cloned cells is necessary for experimentation with them. This paper details a method for the identification of cultured human malignant prostatic epithelial cells derived from metastatic deposits of prostate cancer by localization of a specific rabbit antiserum to human prostatic acid phosphatase in the cells.

Bacterial stimulation and granulocyte inhibition of granulopoietic factor production.

We attempted to determine the effect of live bacteria (Staphylococcus epidermidis) on granulocyte colony-stimulating-factor production by human peripheral blood mononuclear cells (monocytes and lymphocytes) in vitro. Addition of bacteria to mononuclear-cell cultures enhanced colony-stimulating-factor production by these cells, as assayed on both human and mouse bone marrow. Addition of peripheral blood granulocytes to parallel cultures eliminated this enhancement effect, presumably by bacterial removal or inactivation.

Supraclavicular node biopsy in testicular tumors.

Fifty-seven patients with germinal cell carcinoma of the testis were evaluated routinely, with the addition of a supraclavicular node biopsy as a final staging procedure. Five patients showed more extensive disease with the addition of this staging modality.