Kinetics of adhesion molecule expression and spatial organization using targeted sampling fluorometry

Cellular interactions with the vascular wall under flow conditions are controlled, in part, by the density of adhesion molecules on endothelial cells. The spatial arrangement and absolute levels of these molecules over the endothelium are therefore important determinants of cellular localization. Many biochemical and functional studies have characterized the interactions between leukocytes and endothelial monolayers, but no reliable method has been reported for quantifying the spatial expression of adhesion molecules on intact endothelial cell monolayers. We report the development of targeted sampling fluorometry (TSF), which uses standard immunostaining, fluorescence microscopy and digital image analysis techniques to analyze cell surface molecule expression on a cell-by-cell basis. This technique is performed on an intact monolayer and results in cellular intensity distributions that reflect spatial heterogeneity in adhesion molecule expression. We demonstrate the use of targeted sampling fluorometry in a study of the kinetics of tumor necrosis factor alpha-induced activation of human umbilical vein endothelial cell monolayers and show that the spatial patterns of adhesion molecule expression correlate with the locations of bound lymphocytes.     

Byssotoxin A, a secondary metabolite of Byssochlamys fulva

Byssochlamys fulva, isolated from corn, was grown on nutrient-amended shredded wheat medium for 14 days at 25 C. Crude solvent extract from these cultures was toxic to brine shrimp, chicken embryos, and rats. The extract was slightly inhibitory to the germination of of pea seeds, but was nontoxic to ten species of bacteria and one of yeast. One metabolite was isolated, given the trivial name byssotoxin A, and partially characterized chemically and physically.     

The potential of the teaching hospital for the development of prepaid group practices

This paper deals with the development of a hospital based prepaid group practice at Long Island Jewish-Hillside Medical Center. The paper provides an historical perspective of the factors leading to the decision to develop such a Medical Group practice, the difficulties encountered in obtaining conceptual approval from the Medical Center's Board of Trustees and its medical staff, the negotiations between the Medical Center and Blue Cross-Blue Shield of Greater New York as the insurance company which agreed to market the program and to subsidize it in its developmental stage, factors relating to the contractual negotiations between the Medical Center and Blue Cross, the key elements of the negotiated contract from the standpoint of the prepaid group, and the nature of the subsidies provided to ensure a healthy fiscal beginning. The paper highlights the methods used in achieving the desired goals and the development of the Group, sets forth the resistance which other, similar hospitals might anticipate in undertaking such a venture of their own, and highlights the nature and the degree of commitment necessary to bring such a program into being.     

Histochemical observations on the seasonal fluctuations in the follicular atresia and interstitial gland tissue in the house sparrow ovary

A histochemical study has been made of seasonal fluctuations in the follicular atresia and interstitial gland tissue with the ovarian cycles of the house sparrow (Passer domesticus). The atresia of primordial oocytes forms the predominant feature of the quiescent-winter ovary. The building up of interstitial gland tissue of thecal origin. which precedes the breeding activity, is closely related to the atresia of previtellogenic follicles of variable sizes. Interstitial gland cells which accumulate lipid droplets consisting of cholesterol, and/or its esters, triglycerides and some phospholipids, are the steroid secretors. The possible functional significance of different-sized follicular atresia in relation to follicular growth and breeding activity is discussed.