Biomedical subjects
Publications and source records attributed to Z Laron.
Two male children with congenital adrenal hyperplasia due to a 11-beta-hydroxylase defect are described, in whom gynaecomastia developed before institution of therapy, or when the treatment was inadequate. Cortisone in appropriate doses caused the gynaecomastia to disappear.
Widespread subcutaneous lipoatrophy developed in a nineteen year old female diabetic using subcutaneous bovine NPH insulin. Neither rotation of the injection site nor injection of the same insulin into the atrophic areas affected the lesions. Replacement of the bovine insulin by a porcine preparation given by deep intramuscular injection into the center of the atrophic areas resulted in disappearance of the lesions within a short time.
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Luteinizing hormone (LH)-releasing hormone (LH-RH) tests (50 microgram/sq m intravenously) were performed in 112 prepubertal boys ages 13/12 to 11 years (mean +/- standard deviation, 75/12 +/- 16/12 years) suspected of having a testicular disorder because of improperly located testes (77 boys) or hypogonadism (35 boys). Four of the patients were retested within a period ranging from 6 to 16 months. Of the 112 boys tested, 17% were found to have high basal levels of follicle-stimulating hormone (FSH) and 23% were found to have an abnormally high release of FSH after LH-RH administration. Only three patients had abnormally high basal levels of LH and/or elevated LH responses to LH-RH. The basal plasma testosterone levels were found to be normal in all 112 bosy. The fact that plasma FSH levels were elevated more often than LH levels suggests that the tubular elements are damaged more frequently than are the Leydig cells. The surprisingly high incidence of an abnormal response of plasma FSH to LH-RH in boys with mobile testes calls for an increased awareness of the importance of regular examination of these patients until full puberty has been achieved. It is concluded that determination of basal plasma FSH levels and the response to LH-RH stimulation is a useful diagnostic tool for evaluating testicular function in prepubertal boys with suspected pathology of the testes.
Of 108 children being treated at our Institute for primary (nongoitrous) hypothyroidism, tests with radioactive iodine 131I uptake showed that 26 of them (24%) had an ectopic thyroid gland. Four euthyroid children also had anterior swellings of the neck which, in each case, proved to be an ectopic thyroid gland. Of the 30 children studied, 20 were girls and 10 were boys. Nine patients were diagnosed within the first year of life. Growth retardation, manifest in 20 patients, was the most common clinical finding at the time of diagnosis. Delayed bone age was a feature in all of them. Growth, after diagnosis was within normal limits in 83% of the infants who were treated within the first two years of life; only 50% of the children diagnosed later grew within normal limits. Similarly, mental function was best preserved in those patients in whom treatment was initiated within the first two years of life.
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Administration of STZ prior to mating, induced significant impairment in glycogen metabolism in term rat placentae. Glycogen retention was observed in the treated placentae, while glycogen synthetase activity was reduced. The glycogenolytic pathway seemed to proceed mainly through amyloglucosidase enzyme whose activity increased threefold. Glucose-6-phosphatase showed a moderate activation, mainly in the labyrinth zone, while phosphorylase was slightly inhibited. These changes were accompanied by a decrease in placental insulin levels. The possible defensive role played by the placenta in cases of maternal hyperglycemia was postulated.
The sexual maturation in the Prader-Labhart-Willi (PLW) syndrome was investigated in 14 patients, 10 females and 4 males. A wide variability in the pattern of pubertal development was found including delayed puberty in 5 patients and normal puberty in 4 patients; sexual precocity was also observed in 5 patients, true precocious puberty in one patient and incomplete sexual precocity in the form of precocious pubarche in 4 patients. In 5 patients, 3 of them with precocious pubarche, the appearance of the pubertal signs was followed by a delay or arrest in their future development. An LH-RH stimulation test was performed in 11 patients. In the 6 patients who eventually developed normal puberty, the basal levels and the peak responses of both LH and FSH were within the range of those observed in normal controls of the same pubertal stage. In 4 patients showing marked delay or arrest of puberty, the basal levels were normal or low and the responses of LH and FSH to LH-RH were blunted. Priming with repeated LH-RH stimulation in one of the male patients led to an augmented LH response, suggesting a hypothalamic hypogonadotrophism. It is concluded that the lack of uniformity in the pattern of sexual maturation in the PLW syndrome is due to a variability in the location and extent of a hypothalamic lesion, which may comprise an active process continuing beyond the perinatal period.
Two males and three females with ataxia telangiectasia aged from 4 6/12 to 23 years were subjected to an i.v. LH-RH test. All were found to have elevated basal levels of FSH and three had elevated levels of LH. In all the response of FSH to LH-RH was supranormal. In the pubertal and adult females the basal levels of estradiol were low. The laboratory and clinical findings in these patients as well as data reported by others indicated that the primary gonadal failure is an integral part of AT.
Two male patients with congenital cleft lip and palate first seen at ages 10.2 and 21.5 years presented with typical signs of hypothalamic-interior pituitary hormone deficiencies. They were found to lack GH, LH, and FSH and to be partially deficient in TSH and ACTH. Several congenital defects may explain this rare syndrome affecting midline structures in the proximity of the maldeveloped palate, including Rathke's pouch, which migrates distally to develop into the anterior pituitary.
A 9.9-year-old boy and a 9.8-year-old girl with virilising congenital adrenal hyperplasia were subjected to an IV LH-RH (luteinising hormone-releasing hormone) test (so microgram/m2 before initition of therapy with corticosteroids. The pattern of response of LH and follicle-stimulating hormone to LH-RH was found to correspond to the stage of their precocious sexual development and advanced bone age, but not to their chronological age. This finding has implications with regard to the mechanism controlling gonadotrophin secretion at puberty.
The blood glucose of 271 diabetic subjects (140 boys and 131 girls), followed in a diabetes clinic, was determined by three methods: 1) Reflectance Meter (Ames), 2) Eyetone (Ames), and 3) AutoAnalyzer (Technicon). The results were statistically analyzed at four blood glucose concentration ranges (less than 100, 100 to 200, 201 to 300 and greater than 300 mg/dl). The Eyetone instrument and the Reflectance Meter were found to be simple and exact methods for instant glucose determination as compared with the standard AutoAnalyzer technique. The Reflectance Meter was inexact in the blood glucose range of 201 to 300 mg/dl. The Eyetone instrument was reliable within the range of 10 to 400 mg/dl and was found to be useful for quick glucose determination in the clinic or home.
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The plasma insulin response to a standard arginine stimulation test was studied in 247 children and adolescents (177 males and 70 females) with constitutional growth retardation as compared with the response obtained in a matched group of 42 normal subjects and a group of 57 obese subjects. When the insulin response was related to pubertal ratings in the children and adolescents with growth retardation, it was found that the mean fasting levels and mean peak response both rose with the progression of puberty. This tendency was more pronounced in the females. When the insulin response was related to the degree of adiposity as measured by the degree of subscapular skinfold thickness, it was found that the greater the adiposity, the greater was the mean response, with the females showing higher levels than the males in each group. Even when the response in the two sexes was compared in subjects of a similar age and skinfold thickness, the females had a higher mean peak insulin response than did the males.