This study was undertaken to investigate the distribution of vitamin E in the macular and peripheral regions of the human retina, retinal pigment epithelium (RPE) and choroid as a function of age. High-performance liquid chromatography (HPLC) was used to measure alpha- and gamma-tocopherol levels quantitatively using tocol as an internal standard. In 57 out of 70 donor eyes (ages 9-104) the macular region was isolated and the tocopherols analyzed. The conventional brush method and a new vortex method were used to isolate the retinal pigment epithelium cells. Similar trends for the vitamin E levels (increase to the 5th decade, decrease after 7th decade) were found for the macular and peripheral retina and for the macular RPE. In the peripheral RPE a slight continuous increase with age was found. The vitamin E levels are higher in the RPE than in the retina, for both macular and peripheral regions. The amounts of vitamin E/mg protein are lower in the macular retina than in the peripheral retina, whereas in the RPE there is no difference in vitamin E content between macular and peripheral regions. A simple method based on a gentle vortex step was found to offer several advantages over the more generally used isolation of RPE cells based on brushing, and there was no difference in recovery of vitamin E in RPE cells when they were isolated by either isolation technique. It was also found that denominators, used to express the values of vitamin E in tissues should, be used with care since age dependent trends in parameters/denominators could be caused by trends in the denominators only.

Neisseria gonorrhoeae were exponentially killed for 120 min (i.e., they were prevented from forming colonies on agar) by extracts of human neutrophil granules; however, macromolecular synthesis, indicated by incorporation of radiolabeled precursors in trichloroacetic acid-precipitable material, continued at or above zero time control values for 45 min. Protein, deoxyribonucleic acid, and ribonucleic acid synthesis appeared to decrease simultaneously after 45 min. Little or no lysis of gonococci occurred during the first 60 min of incubation. The ions K+, Na+, Ca2+, Cll-, S042and PO43at concentrations of l100 mM did not affect granule extract bactericidal activity. On the other hand, 20 mM Mg2+ completely inhibited killing when initially present along with granule extract or when added within 2 to 5 min after granule extract was added to a suspension of gonococci. Gonococci treated with granule extract, washed, and then incubated in the absence of extract died as if extract were still present. The ability of subinhibitory concentrations of actinomycin D or erythromycin to inhibit growth and protein and nucleic acid synthesis was synergistically increased in the presence of granule extract. The above information suggests that a bactericidal component(s) of human neutrophil granules sticks to gonococci, altering their outer membrane permeability and their ability to divide. MATERIALS AND METHODS Bacteria. N. gonorrhoeae strain F62 was obtained

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