Secreted phosphoprotein I (SPP), also known as 2ar, osteopontin, 44-kDa bone phosphoprotein, bone sialoprotein I, and transformation-related phosphoprotein, is a 41.5-kDa glycosylated phosphoprotein secreted by many mammalian cell lines and expressed in a limited set of tissues. Using a cDNA probe, we found that SPP mRNA, which is barely detectable in normal mouse epidermis, was expressed at moderate-to-high levels in 2 of 3 epidermal papillomas and at consistently high levels in 7 of 7 squamous-cell carcinomas induced by an initiation-promotion regimen. This contrasts with the transient induction we had previously observed after a single application of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). In a set of 5 independently isolated T24-H-ras-transfected mouse C3H 10T1/2 cell lines, the levels of SPP mRNA correlated well with ras mRNA levels and with both experimental and spontaneous metastatic ability. SPP mRNA expression was also elevated in a derivative of mouse LTA cells transfected with genomic DNA from B16F1 melanoma cells and selected for increased experimental metastatic ability in the chick embryo. This apparent association of SPP expression with invasion, progression and metastasis, along with the presence of a functional ArgGlyAsp (RGD) cell adhesion site in SPP (osteopontin), leads us to propose that SPP may act as an autocrine adhesion factor for tumor cells.

This case report involves four dairies in the Willamette Valley, Oregon, which experienced reproductive problems associated with the presence of a large, previously unidentified, peak eluting at 5 min in a standard ergovaline high-performance liquid chromatography assay of perennial ryegrass silage fed to those animals. Mycotoxin analysis of the silage was negative, as was serological screening of the herds for infectious bovine rhinotracheitis, bovine diarrhea virus and Leptospirosis, including culturing of urine for Leptospira hardjo hardjobovis. Prolactin concentrations were low in most cattle, consistent with ingestion of ergot alkaloids. We believe that this peak represents a novel ergot alkaloid-related compound due to its extractability with Ergosil, its detectability due to fluorescence, and its chromatographic retention between ergovaline (mw = 533) and ergotamine (mw = 581). Its molecular weight was calculated as 570 owing to the predominance of a m/z 593.5 ion in the full scan ESI(+)MS and its deduced tendency to complex with Na(+) (as m/z 593) or K(+) (as m/z 609) ions. We offer rationales for elucidation of the structure of this compound, with the closest starting point comprising an m.w. of 566-a fructofuranosyl-(2-1)-O-beta-D-fructofuranoside derivative of 6,7-secoergoline from Claviceps fusiformis. This m.w. requires modifications, such as reduction of two double bonds in the secoergoline component to give the target 570 m.w. Despite the lack of a definitive structure, the analysis herein provides a starting point for eventual elucidation of this apparently new ergot alkaloid, and to guide and encourage further investigation as to its association with endophyte toxicosis in livestock.

An improved technique for rapid screening of sheep flocks for hemoglobin (Hb) type is presented. This technique, isoelectric focusing (IEF) on thin-layer agarose gels is simple, rapid, inexpensive and is suitable for screening large numbers of sheep for Hb type. With this technique, up to 100 sheep blood samples can be prepared, tested and interpreted within 2 h after samples are drawn. The new technique was shown to provide better resolution than polyacrylamide gel electrophoresis (PAGE) and was able to resolve samples in which the Hb had become partially degraded. These same samples could not be resolved by PAGE. The use of a special electroendosmosis-free grade of agarose provided resolution essentially equal to polyacrylamide as a matrix for IEF. The advantages are that the casting of the agarose gels is considerably easier, the focusing of samples is more rapid, staining and destaining times are greatly reduced and hazards from potential neurotoxicity of acrylamide are eliminated. Blood from 138 ewes at the Oregon State University Sheep Center was examined by the new agarose IEF technique to determine and demonstrate its usefulness for screening. No difficulty was encountered with interpretation of any of the samples. Frequencies of the HbA and B alleles were similar to those found in earlier studies when polyacrylamide tube gel electrophoresis was used. The observed frequencies were also similar to those expected with the population in Hardy-Weinberg equilibrium.