Fluorophotometry and the rate of aqueous flow in man. I. Instrumentation and normal values

A new objective fluorophotometer, based on a previous model but with changes in electronic circuitry, was designed and built. The fluorometric method was applied to 38 normal eyes to obtain the aqueous outflow rate and fluorescein decay constant. Aqueous outflow rate has a direct correlation with the anterior chamber depth and an inverse correlation with age. The aqueous flow rate is higher in whites than in blacks, but in our sample, mean pressure was lower in whites. Acetazolamide decreases the aqueous flow rate and the fluorescein constant; the mean decrease in 10 eyes of 5 patients was approximately 38% and 22%, respectively. Fluorophotometry gives a higher value for the aqueous outflow rate than that calculated by tonography.     

High-frequency audiometry above 8,000 Hz

Human auditory sensitivity for the frequencies 8, 10, 12, 16, 18, and 20 kHz was examined in a group of 41 female university students ranging in age from 19 to 22 years. The purpose of this study was twofold: to determine the feasibility of high-frequency testing using procedures routinely employed in clinical audiometry and to collect normative data using this procedure on a young adult population. A modified Hughson Westlake procedure was employed and thresholds were obtained for both ears of each subject. It was noted that for the 20-kHz tone only 52% of the subjects tested were able to respond. Statistical analysis revealed no significant threshold differences between right or left ears for all subjects at any frequency. The approach described in the present study provided reliable thresholds and was found to be clinically feasible. Comparisons were made with similar previous studies and the results of the present study were found to be in general, overall agreement.     

Immunohistochemical characterization of proliferation, oestrogen receptor and progesterone receptor expression in endometriosis: comparison of eutopic and ectopic endometrium with normal cycling endometrium

Recent studies examining oestrogen and progesterone receptor status and the proliferative activity of endometriotic lesions have produced conflicting reports. This study aimed to clarify the receptor status and proliferative activity of eutopic and ectopic endometrium from women with endometriosis and endometrium from normal women. Progesterone and oestrogen receptor expression and proliferative activity were studied in eutopic and ectopic endometrium from 30 women with endometriosis and in endometrium from 30 normal cycling women using microwave-pretreated paraffin-embedded sections stained with an avidin-biotin peroxidase technique. Progesterone and oestrogen receptor expression in the control endometrium did not differ from that of eutopic endometrium from women with endometriosis. Oestrogen receptor expression in ectopic endometrium increased from the proliferative to the late secretory phase. Epithelial progesterone receptor expression decreased during the cycle. Oestrogen receptor expression in both epithelium and stroma of ectopic endometrium was significantly higher than in eutopic endometrium throughout the cycle. In contrast, stromal progesterone receptor expression tended to be reduced in ectopic endometrium compared with eutopic tissue. Epithelial progesterone receptor expression was increased in ectopic endometrium but only in the late secretory phase. Although proliferative activity in the epithelium of control and eutopic endometrium was reduced from the proliferative to the late secretory phase, stromal activity did not vary. The proliferative activity in ectopic endometrium remained low and constant throughout the cycle. In the proliferative and early secretory phases, the proliferative activity of eutopic endometrium was increased compared with ectopic endometrium, but in the late secretory phase, levels were comparable. These findings challenge previous reports which have suggested that oestrogen receptors are reduced in ectopic tissue. This may have clinical implications for the development of novel treatments for endometriosis.     

Comparative studies of phosvitin from chicken and salmon egg yolk

1. A method developed for the isolation of phosvitin from chicken egg yolk was successfully applied to the isolation of phosvitin from salmon eggs. 2. Salmon roe phosvitin is smaller in molecular size than chicken egg phosvitin. 3. Circular dichroism spectra of all phosvitins investigated displayed good similarities with spectra showing characteristics of unordered and beta-sheet secondary structure. 4. The main component in the Fourier transform infrared spectra of chicken egg phosvitin is indicative of unordered conformation, whereas the Fourier infrared data of the salmon egg phosvitin are consistent with more of beta-sheet structure compared to the chicken egg phosvitin.     

Alternate iron transport pathway. Mobilferrin and integrin in K562 cells

A transferrin-independent iron transport system in cells containing transferrin receptors was described previously by several investigators. Prior studies did not identify the proteins involved in this alternate iron transport pathway. Using a human-derived erythroleukemia tissue culture line, iron-binding proteins were isolated from cytosol and cell membranes. The cytosol protein was soluble in 60% ammonium sulfate, had a molecular mass similar to mobilferrin (56 kDa), and reacted with anti-mobilferrin antibodies. The water-insoluble radiolabeled protein was solubilized with Nonidet P-40 and immunoprecipitated with monoclonal antibody against beta 3 human integrin. Pulse-chase studies suggested sequential passage of iron to integrin, mobilferrin, and ferritin, respectively. Thus, the alternate iron transport pathway contained proteins similar to those observed in intestinal cells which did not possess transferrin receptors on their absorptive surface. The alternate iron transport pathway is only partially shared with zinc and cadmium. Mobilferrin bound zinc and iron competitively, but the two metals were not transported competitively into K562 cells. Immunoprecipitates of integrin containing radiozinc were obtained with a monoclonal antibody against beta 1 human integrin. This suggested iron and zinc may utilize different integrins to passage the cell membrane.