Marvin L. Sears

Photocoagulation Treatment of Proliferative Diabetic Retinopathy: The Second Report of Diabetic Retinopathy Study Findings

Data from the Diabetic Retinopathy Study (DRS) show that photocoagulad inhibited the progression of retinopathy. These beneficial effects were noted to some degree in all those stages of diabetic retinopathy which were included in the Study. Some deleterious effects of treatment were also found, including losses of visual acuity and constriction of peripheral visual field. The risk of these harmful effects was considered acceptable in eyes with retinopathy in the moderate or severe retinopathy in the moderate or severe proliferative stage when the risk of severe visual loss without treatment was great. In early proliferative or severe nonproliferative retinopathy, when the risk of severe visual loss without treatment was less, the risks of harmful treatment effects assumed greater importance. In these earlier stages, DRS findings have not led to a clear choice between prompt treatment and deferral of treatment unless and until progression to a more severe stage occurs.

Enzyme-linked immunosorbent assay of substance P: A study in the eye

Abstract: A solid phase enzyme‐linked immunosorbent assay for quantitation of substance P is presented. The assay measures the capacity of soluble substance P to compete with the solid phase antigen for a limited quantity of specific substance P antibody. The solid‐phase antigen consists of a synthetic substance P. poly‐D‐glutamic acid conjugate coated to polystyrene micro‐ELISA plate wells. Soluble substance P and antibodies to substance P are first preincubated together and then added to the wells containing solid‐phase antigen. Subsequently the wells are incubated with anti‐antibodies conjugated to alkaline phosphatase. The wells are finally incubated with p‐nitrophenyl phosphate and the absorbance is read in a spectrophotometer 16‐24 h after the start of the assay. The threshold for detection of substance P was 5‐10 pg per well (0.25 ml). Substance P was extracted from rabbit eyes and the values obtained with the present method are compared with previously reported values based on radioimmunoassay.

Caution on the Preoperative use of Topical Timolol

Timolol is a nonselective beta 1 - and beta 2 -adrenergic blocking agent. Systemic antagonism of the beta 1 -receptor after topical ocular administration of timolol has been reported to be responsible for such cardiovascular side effects as bradycardia, arrhythmias, systemic hypotension, cardiac failure, and, possibly, myocardial infarction and sudden death. 1,2

The Eye: Volume 5, Comparative Physiology,

Developing new information about the human eye is a difficult proposition at best, therefore, it is essential that information derived from other animal species be available to those interested in solving problems in the human. Furthermore, basic problems concerned with embryogenesis of molecules, cells, and tissues; transport of nutrients and how they are utilized; and the development of specific microstructures and macrostructures within the eye all have intrinsic interest. This volume contains five chapters dealing with the vascular system, fluid system, the outflow pathway, and two sections on the crystalline lens. It is a volume that serious workers in ocular physiology will find useful. The book contains a wealth of basic information that will provide an excellent background for the laboratory worker who wishes to approach any of these problems in ocular physiology. In addition, the clinical researcher will be able to improve his scholarship with the information provided in