The Electrophoretic Index : A Parameter of Thyroid Function

Abstract

Summary The capacity of serum thyroxine‐binding globulin (T.B.G.) and albumin to bind added radiothyroxine in vitro has been utilized as a diagnostic test of thyroid function. After electrophoresis on cellulose acetate, the ratio of radioactivity in the α1‐ to α2 globulin zone to the total radioactivity present in the protein area, expressed as a percentage, is termed the electrophoretic index (E. I.). The normal range of values lies between 61% and 75% (mean, 68·9±3·86). The hyperthyroid range is below the lower limit (mean, 54·9±6·03), while hypothyroid values are above the upper limit (mean, 79·8±2·90). The E.I. for normal pregnancy is invariably over 80%. The clinical conditions under which the E.I. is most contributory to correct diagnosis, in the presence of conflicting protein bound iodine and resin uptake results, include treated thyroid disease and suspected thyroid dysfunction in which there is a high blood level of iodine as a result of laboratory contamination, the use of X‐ray media or the intake of iodine preparations. In the case of those patients who have an abnormal binding capacity of T.B.G. because of changes in the protein pattern which are either inherent, disease‐induced, or the result of the intake of drugs or hormones, the estimation of the E.I. is of value in establishing the underlying cause. A knowledge of the E.I. is also helpful in the detection of hypothyroidism in early infancy, and its use gives consistently reliable results in the diagnosis of thyrotoxicosis coinciding with pregnancy.

Serum Triiodothyronine, Thyroxine and Thyroid-Stimulating Hormone in Endemic Goiter: A Comparison of Goitrous and Nongoitrous Subjects in New Guinea†

“…Serum T.< and TSH were determined by double antibody radioimmunoassay (RTA) methods as previously described (16,17). Serum TBG capacity was estimated by a modification of a previously published method (18). The normal ranges for the three hormones and for TBG were as follows: T,, 4.6-10.0 ng/100 ml; T :1 , 75-177 ng '100 ml; TSH, < 0.2-3.4 uU/ml; TBG, 30-40 ug 100 ml.…”

The Predictive Value of Thyroid “Test Profile” in Habitual Abortion

“…Thiiodothyronine-resin uptake (T3U), and electrophoretic index (EI) were measured by methods previously described (Winikoff, 1968 and1971). Electrophoretic index was expressed as a percentage uptake of added radiothyroxine bound to (a1-a2) globulin area after electrophoretic separation (Taylor and Winikoff, 1968). The total binding capacity of thyroxine binding globulin (TBG) was assayed by an adaptation of the EI procedure (Taylor and Winikoff, 1968).…”

“…Electrophoretic index was expressed as a percentage uptake of added radiothyroxine bound to (a1-a2) globulin area after electrophoretic separation (Taylor and Winikoff, 1968). The total binding capacity of thyroxine binding globulin (TBG) was assayed by an adaptation of the EI procedure (Taylor and Winikoff, 1968). The serum was incubated with a mixture of a "cold" and radioactive thyroxine in suitable proportions to achieve an added load of 100 pg Tz per 100 ml of serum.…”

“…in pregnant women who aborted previously (Group 2) M-M, during a miscarriage (Group 4) 0-0, and in pregnant women who subsequently aborted (Group 3) 0 (single tests). The single hatched area represents the normal non-pregnant stage; the double hatching indicates the raising of the limit of normal in pregnancy (Taylor and Winikoff, 1968). * First significant deviation from non-pregnant mean.…”

Pharmaceutical Sciences—1968. A Literature Review of Pharmaceutics

“…Included among these were articles on the generalities of ophthalmic preparations, present requirements for the quality of eye drops, and eye drops as a ready medicinal form (20)(21)(22)(23). Specific preparations of eye drops were noted in which the preparations contained lachesine and boric acid, antibiotics, merthiolate, and pilocarpine (27)(28)(29)(30). Specific preparations of eye drops were noted in which the preparations contained lachesine and boric acid, antibiotics, merthiolate, and pilocarpine (27)(28)(29)(30).…”