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A sterol carrier protein2 (SCP2)-like activity has been demonstrated in rat intestinal mucosal homogenates and in isolated intestinal cells from both crypt and villus zones. The results indicate the presence of a protein with similar molecular weight and antigenicity to that of authentic SCP2 purified from rat liver cytosol. Like liver SCP2, mucosal cytosol stimulates pregnenolone production in rat adrenal mitochondria and acyl coenzyme A:cholesterol acyltransferase activity of liver and mucosal microsomes. The distribution of SCP2-like activity as determined by radioimmunoassay indicates high levels in mitochondria and cytosol and relatively lower levels in microsomes and in brush-border membranes. The widespread distribution of SCP2-like protein in the intestine is consistent with potential transfer functions in all phases of cholesterol processing.

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Acyl coenzyme A:cholesterol acyl transferase and/or cholesterol esterase may regulate the esterification and absorption of exogenous cholesterol. To assess this, mucosal acyl coenzyme A:cholesterol acyl transferase activity was inhibited selectively with three different drugs [Sandoz #58-035, inhibitor 1; Lederle inhibitor 2 and inhibitor 3] and the effect upon the absorption of a [4-14C]cholesterol meal was studied in the lymph fistula rat. Compared to control rats, ACAT activity measured in mucosal homogenates from the drug-treated rats was reduced 80-90%, 40%, and 30%, respectively, during the predicted time-frame for maximum mucosal esterification of cholesterol (i.e., after cholesterol is fed and before it appears in lymph). In contrast, [14C]cholesterol absorption in the drug-treated animals was unchanged from controls [5.7 +/- 1.2 (inhibitor 1) vs. 5.4 +/- 1.6 mumol/6 hr (control); 6.1 +/- 2.1 (inhibitor 2) and 5.2 +/- 1.5 (inhibitor 3) vs. 4.1 +/- 1.3 mumol/6 hr (control)]. Of the absorbed [14C]cholesterol, approximately 75% was esterified in all groups. Cholesterol esterase activity measured in the drug-treated rats was unchanged compared to controls nor did the drugs inhibit this enzyme in vitro. Under the conditions of this study, drugs causing substantial inhibition of acyl coenzyme A:cholesterol acyl transferase activity had no effect on the absorption of exogenous cholesterol.

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It has been suggested that glaucomatous field loss may progress on the basis of ischemia of the optic nerve head alone after the intraocular pressure has been controlled. Bishydroxycoumarin (Dicumarol) has been reported to be of benefit in such situations. A review of 551 consecutive glaucoma records did not support this theory. Apparent progression of field loss at intraocular pressures of 20 mm Hg or less was either due to artifacts in field testing or to a pressure that was still too high. A pilot study suggested that bishydroxycoumarin was of no benefit in these situations.

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A portable system for external photography combines a focusing lamp and movable flash unit with a wide focusing range. The system is arranged to operate from a single two-position trigger and may be hand-held or mounted on a slitlamp stand. It is designed for use in general ophthalmology in a multilaned office practice or bedside use in a hospital situation.

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Retinitis pigmentosa is occasionally associated with a vasculopathy of the Coats type. Although the clinical appearance of the vaculopathy is similar to that seen in the usual patient iwth Coats's disease, cases associated with retinitis pigmentosa are usually bilateral, equally common in females, and are not seen in childhood. These findings suggest a different etiological process. We speculate that the etiology in such cases may be related to the vascular narrowing and slower circulation known to occur in some retinitis pigmentosa patients.

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The filtration procedures of trephine, iridencleisis, and corneoscleral cautery are compared to show the superiority of the latter. Pathologic vertification of the three operations suggests the reason for success. Several changes in the original technique as described by Schele are suggested.

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We believe that most cataract extraction procedures may be good in competent hands, but that complicated techniques do not necessarily give the best results. With inexperienced residents, or the occasional surgeon, a safe, simple method needs to be used until the skill of the operating surgeon may warrant more advanced techniques. A simple cataract procedure consisting of local anesthesia, limbal-based conjunctival flap, 3 postplaced 7-0 mildly chromicized gut sutures, 2 peripheral iridotomies and tumbling extraction of the lens with capsule forceps (indirect acting) is described. The low incidence of complications of all types would seem to negate the current trend of complicating the procedure. Further reports will include large series of cataracts done by resident physicians rather than by the instructors to try to further justify this position.

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