Growth hormone release after synthetic 1-24 ACTH: effects of estrogen and sex.

Recent reports have demonstrated that growth hormone (GH) is inconsistently released after intravenous administration of synthetic 1-24 ACTH. This study was designed to evaluate the role of estrogens in mediating this response. 250 mug of synthetic 1-24 ACTH were administered to 8 men in 12 studies and 6 women in 11 studies. None of the men exhibited a rise in GH after 1-24 ACTH, while the women exhibited a significant increase. Pretreatment of 5 of these men with 100 mug of ethinyl estradiol daily for 3 days did not alter GH response from the initial studies. Pretreatment with 10 mg of diethylstilbesterol daily for 3 days, however, resulted in a rise in GH which was similar to the female group. It is concluded that the variable GH responses to synthetic 1-24 ACTH may be in part due to prevailing concentrations of sex steroids and their effect on the hypothalamic-pituitary GH release mechanism.     

Insulinoma with low circulating insulin levels: the diagnostic value of proinsulin measurements.

Hypoglycemia coexisting with very low plasma immunoreactive insulin concentrations was found in a 78-year-old woman with an insulinoma. However, the absolute proinsulin levels during hypoglycemia were elevated (0.9 to 1.4 ng/ml), accounting for 66.5% of the total circulating immunoreactive insulinlike material. The raised serum proinsulin concentrations together with an abnormal proinsulin:insulin ratio proved to be of critical importance in establishing the diagnosis of an islet-cell tumor in this patient.     

Lumbosacral plexopathy after gynecologic surgery: Case report and review of the literature

Very unusual lumbosacral plexopathy symptoms appearing after an uncomplicated abdominal hysterectomy prompted a review of the literature. The patient's symptoms spanned the somatic and autonomic systems and ranged from T-11 to S-4; a cause that would explain these is perplexing. Pelvic neuroanatomy and plexopathy symptoms are presented. Etiologies of neurologic symptoms are discussed and preventive strategies are explored. (Am J Obstet Gynecol 1996;174:1769-78.)     

Clinical correlations of serum proinsulin-like material in islet cell tumours

To examine the possibility that the concentration of circulating proinsulin-like material (PLM) might be helpful in evaluating the therapeutic response of patients with islet cell tumours, serum levels of PLM in three patients with islet cell tumours were correlated with hypoglycaemic symptoms and plasma glucose concentrations before and after treatment. In two patients ranges of fasting PLM concentration were 0.21-0.29 and 0.91-0.93 ng/ml, respectively, before treatment. After surgical excision of their islet cell adenomas, PLM concentrations decreased to 0.06-0.09 and 0.03-0.05 ng/ml. Insulin concentrations were low preoperatively in both patients and were unchanged postoperatively. The resulting relief from hypoglycaemia was paralleled by a reduction of PLM, with no significant change in insulin. In a third patient, treatment with streptozotocin resulted in marked symptomatic improvement, a 65% reduction in PLM concentration, but no significant change in insulin levels. Relapse was associated with increasing frequency of hypoglycaemic symptoms and increasing PLM concentrations. These findings suggest that changes in the levels of serum PLM may prove to be a sensitive indicator of the response of islet cell tumours to therapy.     

Preliminary Screening of Blood Donors with the Microhematocrit Test for Red Cell Volume and the Plasmacrit Test for Syphilis (HCT-PCT Method)

The micro HCT-PCT method and the CuSO₄—VDRL method were compared in the screening of 10,598 consecutive blood donors. The more accurate micro HCT at 40 to 60 per cent limits (13.5 Gm. per cent minimum Hgb.) rejected 4 per cent of the donors as compared to 2.9 per cent with CuSO₄ at the 12.5 Gm. per cent Hgb. level. Based on an earlier study comparing the CuSO₄ method at the 12.5 and 13.5 Gm. per cent levels in over 7,000 donors, the rate at 13.5 Gm. per cent would have been 3.2 per cent. The reasons for the difference between the two test methods are presented. The opportunity to inspect the plasma resulted in the advance rejection of 454 donors (4.3%) for excessive chyle, six for apparent icterus, and one for abnormal buffy coat. The rate of positive serology was 2.2 per cent with the PCT test, again permitting advance rejection, as compared to a rate of 1.7 per cent with the VDRL, which is done after donation. There were nine negative PCT tests which were positive with the VDRL during a period of technical difficulties with outside diameter variation in the special PCT capillaries, eight of which were confirmed as false positive VDRL results. There were no negative PCT tests with positive VDRL results after this problem was corrected. The HCT-PCT method of donor screening should be substituted for the CuSO₄—VDRL method because it provides a better quality of donor screening through a more accurate measure of red cell normalcy and advance rejection of donors with excessive chyle, icteric plasma, abnormal buffy coat or hematocrit, as well as those with a positive serology. This advantage is greatly enhanced, since use of the method results in a savings in operating costs of over 6 per cent, through the advance rejection of donors whose blood would have been unusable.     

Effect of contraceptive steroids on arginine-stimulated glucagon and insulin secretion in women: I-Lipid physiology.

To evaluate the effect of contraceptive steroids on endogenous glucagon and insulin secretion, theta-arginine was infused intravenously in normal young women before and during selective steroid treatment. The effect of the combination of an estrogen derivative (mestranol), plus norethindrone (Norinyl, Syntex) was compared to the effect of ethinyl estradiol alone and to norethindrone alone. All three steroid schedules resulted in suppression of aminogenic insulin secretion. However, glucagon secretion was reduced only with ethinyl estradiol alone or the combination of mestranol plus norethindrone. In accordance with previous reports, treatment with an ethinyl estradiol derivative alone or in combination with norethindrone resulted in a tendency for elevated serum lipid concentration, while norethindrone alone resulted in a significant reduction in serum lipid concentration. These observations suggest an inverse relationship between aminogenic glucagon secretion and serum lipid concentration as influenced by contraceptive steroids. It is suggested that the metabolic effects of these steroids may be mediated in part by the associated alterations in pancreatic hormone secretory capacity.     

Thymol Turbidity and Thymol Flocculation Tests As a Screening Technic to Detect Blood Donors Carrying the Hepatitis Virus

Six-month follow up study showed a hepatitis case rate of 1.55% in 905 patients receiving "abnormal" blood and 0.88% in 1,480 receiving nothing but "normal" blood, based on screening at the 95% confidence level of 8.0 T.T. units in clear sera and in lipemic sera of 8.0 units or more with a positive flocculation test (from studies of 52,662 consecutive donors reported in Part I). Significantly, screening at the 99% level gave less specific results: a 1.06% rate in controls and 1.42% in the test cases. The observed differences in rates are not statistically significant: twice the standard error of the difference in percentages is 0.9%, the Chi Square test showed P = 0.15 (at 95%) and 0.70 (at 99%). The donor (unit) case rates were essentially identical (0.346) in the test series and in the controls at both screening levels and the difference in hepatitis case rates was exactly proportional to the difference in the average donor exposure of the two groups at each screening level. The two groups of cases received 14% of the total blood units available and this was representative of the total available as judged by the mean T.T. values of blood received by the study cases. There was a steady increase in the hepatitis case rate from 0.6% in single unit transfusions (29% of cases) to 2.6% when four units were used, with a rate of 1.1% in those receiving five units or more (19%), suggesting the risk of hepatitis is maximal in transfusions of four or more units. Cogent reasons are presented for abandoning attempts to use nonspecific liver function tests for donor screening to eliminate significant numbers of donor carriers.