Study protocol for a Developmental Epidemiological Study of Children born through Reproductive Technologies (DESCRT)

STUDY QUESTIONS

The primary objective of this study is to determine what parental factors or specific ART may influence the risk for adverse cardiometabolic outcomes among children so conceived and their parents. The secondary objective of this study is to prospectively examine the effects of infertility or ART on the intrauterine environment, obstetric and neonatal outcomes.

WHAT IS KNOWN ALREADY

Pregnancies conceived with ART are at an increased risk of being affected by adverse obstetric and neonatal outcomes when compared to spontaneously conceived (SC) pregnancies among fertile women. Small cohort studies have suggested ART-conceived children may have a higher risk of long-term cardiometabolic disturbances as well. Currently, few studies have compared long-term cardiometabolic outcomes among ART-conceived children and non-IVF treated (NIFT) children, to children conceived spontaneously to parents with infertility (subfertile parents).

STUDY DESIGN SIZE DURATION

The Developmental Epidemiological Study of Children born through Reproductive Technologies (DESCRT) is a prospective cohort study that aims to: establish a biobank and epidemiological cohort of children born to subfertile or infertile parents who either conceived spontaneously (without assistance) or used reproductive technologies to conceive (all offspring were from couples assessed and/or treated in the same institute); prospectively examine the effects of infertility or ART on the intrauterine environment, obstetric and neonatal outcomes; and determine what parental factors or ART may influence the cardiometabolic risk of children so conceived. Pregnancies and resultant children will be compared by mode of conception, namely offspring that were conceived without medical assistance or SC or following NIFT, IVF with fresh embryo transfer or frozen embryo transfer (FET), and by fertilization method (conventional versus ICSI). DESCRT has a Child group evaluating long-term outcomes of children as well as a Pregnancy group that will compare obstetric and neonatal outcomes of children conceived since the commencement of the study. Recruitment started in May of 2017 and is ongoing. When the study began, we estimated that ∼4000 children would be eligible for enrollment.

PARTICIPANTS/MATERIALS SETTING METHODS

Eligible participants are first-trimester pregnancies (Pregnancy group) or children (Child group) born to parents who were evaluated at an infertility center in the University of California, San Francisco, CA, USA who were SC or conceived after reproductive treatments (NIFT, IVF ± ICSI, FET). Children in the Child group were conceived at UCSF and born from 2001 onwards. In the Pregnancy group, enrollment began in November of 2017.The primary outcome is the cardiometabolic health of offspring in the Child group, as measured by blood pressure and laboratory data (homeostatic model assessment for insulin resistance (HOMA-IR), oral glucose disposition). There are several secondary outcome measures, including: outcomes from parental survey response (assessing parent/child medical history since delivery-incidence of cardiometabolic adverse events), anthropomorphic measurements (BMI, waist circumference, skinfold thickness), and laboratory data (liver enzymes, lipid panel, metabolomic profiles). In the Pregnancy group, outcomes include laboratory assessments (bhCG, maternal serum analytes, soluble fms-like tyrosine kinase-1 (sFLT-1), and placental growth factor (PlGF)) and placental assessments (placental volume in the second and third trimester and placental weight at delivery). Importantly, aliquots of blood and urine are stored from parents and offspring as part of a biobank. The DESCRT cohort is unique in two ways. First, there is an extensive amount of clinical and laboratory treatment data: parental medical history and physical examination at the time of treatment, along with ovarian reserve and infertility diagnosis; and treatment specifics: for example, fertilization method, culture O₂ status, embryo quality linked to each participant. These reproductive data will aid in identifying explanatory variables that may influence the primary cardiometabolic outcomes of the offspring-and their parents. Second, the DESCRT control group includes pregnancies and children SC from parents with subfertility, which may help to assess when infertility, as opposed to reproductive treatments, may be affecting offspring cardiometabolic health.

STUDY FUNDING/COMPETING INTERESTS

This study is funded by the National Institutes of Health NICHD (1R01HD084380-01A1). A.J.A. is a shareholder in Carrot and consultant for Flo Health. The other authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

NCT03799107.

TRIAL REGISTRATION DATE

10 January 2019.

DATE OF FIRST PATIENT’S ENROLLMENT

10 May 2017.

Effects of a Mindfulness-Based Intervention on Distress, Weight Gain, and Glucose Control for Pregnant Low-Income Women: A Quasi-Experimental Trial Using the ORBIT Model

Background

Stress can lead to excessive weight gain. Mindfulness-based stress reduction that incorporates mindful eating shows promise for reducing stress, overeating, and improving glucose control. No interventions have tested mindfulness training with a focus on healthy eating and weight gain during pregnancy, a period of common excessive weight gain. Here, we test the effectiveness of such an intervention, the Mindful Moms Training (MMT), on perceived stress, eating behaviors, and gestational weight gain in a high-risk sample of low income women with overweight/obesity.

Method

We conducted a quasi-experimental study assigning 115 pregnant women to MMT for 8 weeks and comparing them to 105 sociodemographically and weight equivalent pregnant women receiving treatment as usual. Our main outcomes included weight gain (primary outcome), perceived stress, and depression.

Results

Women in MMT showed significant reductions in perceived stress (β = − 0.16) and depressive symptoms (β = − 0.21) compared to the treatment as usual (TAU) control group. Consistent with national norms, the majority of women (68%) gained excessive weight according to Institute of Medicine weight-gain categories, regardless of group. Slightly more women in the MMT group gained below the recommendation. Among secondary outcomes, women in MMT reported increased physical activity (β = 0.26) and had lower glucose post-oral glucose tolerance test (β = − 0.23), being 66% less likely to have impaired glucose tolerance, compared to the TAU group.

Conclusion

A short-term intervention led to significant improvements in stress, and showed promise for preventing glucose intolerance. However, the majority of women gained excessive weight. A longer more intensive intervention may be needed for this high-risk population.

Clinical Trials.gov #NCT01307683.

Hypothalamic obesity in children

Hypothalamic obesity is an intractable form of obesity syndrome that was initially described in patients with hypothalamic tumours and surgical damage. However, this definition is now expanded to include obesity developing after a variety of insults, including intracranial infections, infiltrations, trauma, vascular problems and hydrocephalus, in addition to acquired or congenital functional defects in central energy homeostasis in children with the so-called common obesity. The pathogenetic mechanisms underlying hypothalamic obesity are complex and multifactorial. Weight gain results from damage to the ventromedial hypothalamus, which leads, variously, to hyperphagia, a low-resting metabolic rate; autonomic imbalance; growth hormone-, gonadotropins and thyroid-stimulating hormone deficiency; hypomobility; and insomnia. Hypothalamic obesity did not receive enough attention, as evidenced by rarity of studies in this group of patients. A satellite symposium was held during the European Congress of Obesity in May 2011, in Istanbul, Turkey, to discuss recent developments and concepts regarding pathophysiology and management of hypothalamic obesity in children. An international group of leading researchers presented certain aspects of the problem. This paper summarizes the highlights of this symposium. Understanding the central role of the hypothalamus in the regulation of feeding and energy metabolism will help us gain insights into the pathogenesis and management of common obesity.

Bariatric surgery in a patient with complete MC4R deficiency

Bariatric surgery is often successful for treatment of severe obesity. The mechanisms of weight loss after bariatric surgery and the role of central energy homeostatic pathways in this weight loss process are not well understood. The study of individuals with complete loss of function of genes important in the leptin-melanocortin system may help establish the significance of these pathways for weight loss after bariatric surgery. We describe the outcome of bariatric surgery in an adolescent with compound heterozygosity and complete functional loss of both alleles of the melanocortin 4 receptor (MC4R). The patient underwent laparoscopic adjustable gastric banding and truncal vagotomy at years of age, which resulted in initial, but not long-term weight loss. Our experience with this patient suggests that complete MC4R deficiency impairs response to gastric banding and results in poor weight loss after this surgery.

A multicenter, randomized, double-blind, placebo-controlled, dose-finding trial of a long-acting formulation of octreotide in promoting weight loss in obese adults with insulin hypersecretion

OBJECTIVE

To compare changes in weight in obese patients who received long-acting octreotide (octreotide LAR) at one of three dose levels (20, 40, or 60 mg) or placebo over 6 months and to identify the lowest dose of octreotide LAR that safely achieved optimal weight loss.

DESIGN

Randomized, double-blind, placebo-controlled trial of octreotide LAR at three dose levels.

PATIENTS

A total of 172 adults (28 men and 144 women) with at least moderate obesity (body mass index (BMI) range 30-65 kg/m2) and evidence of insulin hypersecretion were enrolled. Patients were predominantly either Caucasian (50.0%) or African American (45.3%). The mean age (38 +/- 11 year), weight (110.7 +/- 23 kg), and BMI (39.8 +/- 6.5 kg/m2) were similar across the four treatment groups.

MEASUREMENTS

Efficacy measures included weight, BMI, fasting serum glucose; triglycerides; percentage of total body fat and abdominal fat as measured by dual-energy X-ray absorptiometry; skin fold thickness; waist-to-hip circumference; leptin; percentage of carbohydrates, fat, and protein ingested; nutritional evaluation (including dietary analysis--3-day food record); quality of life (QoL; using the Impact of Weight on Quality of Life-Lite); Beck Depression Inventory; and Carbohydrate Craving Questionnaire. Safety measures included medical history, vital signs, physical examinations, hematology, blood chemistries, thyroid function tests, hemoglobin A1c, gallbladder ultrasound, electrocardiograms, and adverse events.

RESULTS

After 6 months of treatment, patients receiving 40 or 60 mg of octreotide LAR experienced statistically significant weight loss compared to baseline, with mean differences from placebo in percent weight change of -1.98 and -1.87%, respectively. This finding was accompanied by statistically significant mean decreases in BMI compared to baseline, that is, a mean decrease of 0.73 and 0.79 kg/m2 for the 40 and 60 mg treatment arms, respectively. The observed weight loss was progressive during the 6-month treatment in the two higher dose groups. The lowest dose to reach statistical significance in weight loss after 6 months' treatment was 40 mg. Post hoc analysis revealed a 3.5-3.8% weight loss at month 6 in the two higher dose groups among Caucasian patients having insulin secretion greater than the median of the cohort, defined as CIR(gp) (corrected insulin response at the glucose peak) > or = 1.43. There were no statistically significant changes in QoL scores, body fat, leptin concentration, Beck Depression Inventory, or macronutrient intake. Mean changes of blood glucose AUC(0-180 min) during an oral glucose tolerance test in patients taking octreotide LAR were 39-40 mg/dl h higher than those on placebo. A total of 7-21% of the patients taking octreotide LAR reached a 5% or greater decrease in body weight from Baseline, compared to 11% for the placebo group. This was not statistically significant. The most common adverse events included diarrhea, headache, cholelithiasis, nausea, and abdominal pain.

CONCLUSION

Octreotide LAR given at 40 or 60 mg resulted in statistically significant weight loss. A post hoc analysis stratifying patients by race and CIR(gp) indicated that Caucasian patients with the greater degree of insulin hypersecretion appeared to derive the most benefit from treatment. The observed safety profile was consistent with the known effects of octreotide from previous studies.

Obesity, leptin resistance, and the effects of insulin reduction

Leptin resistance is a hallmark of obesity, but its etiology is unknown, and its clinical measurement is elusive. Leptin-sensitive subjects have normal resting energy expenditure (REE) at a low leptin concentration, while leptin-resistant subjects have a normal REE at a higher leptin concentration; thus, the ratio of REE:Leptin may provide a surrogate index of leptin sensitivity. We examined changes in REE and leptin in a cohort of 17 obese subjects during experimental weight loss therapy with the insulin-suppressive agent octreotide-LAR, 40 mg i.m. q28d for 6 months. Six subjects lost significant weight (>10%) and BMI (>-3 kg/m(2)) with a 34% decline in leptin and a 46% decrease in insulin area under the curve (IAUC) to oral glucose tolerance testing. These subjects maintained their pretreatment REE, and thus exhibited a rise in REE:Leptin, while the other 11 showed minimal changes in each of these parameters. For the entire cohort, the change in IAUC correlated negatively with the change in REE:Leptin. These results suggest that the REE:Leptin ratio, while derivative, may serve as a useful clinical indicator of changes in leptin sensitivity within obese subjects. They also support the possibilities that hyperinsulinemia may be a proximate cause of leptin resistance, and that reduction of insulinemia may promote weight loss by improving leptin sensitivity.

Race affects insulin and GLP-1 secretion and response to a long-acting somatostatin analogue in obese adults

OBJECTIVE

This study investigated (1) the effect of octreotide-LAR (Sandostatin-LAR Depot; Novartis) on the enteroinsular axis in a biracial cohort of severely obese adults, (2) whether octreotide suppression of insulin secretion occurs by both a direct beta-cell effect and through mediating a glucagon-like peptide 1 (GLP-1) response, and (3) whether differences in GLP-1 concentrations could explain racial differences in insulin concentrations.

DESIGN

Prospective, open-label trial using a pre-post test design.

SETTING

Single university, clinical research center.

SUBJECTS

In all, 42 healthy, severely obese Caucasian and African-American (AA) adults (93% female, 64% Caucasian, age=37.8+/-1.2 y, weight=123+/-4.2 kg, BMI=44.5+/-1 kg/m(2)), recruited through physician referral and newspaper ads, participated in the study.

INTERVENTIONS

Indices of beta-cell activity, insulin and GLP-1 response before and during a 75-gm oral glucose tolerance test were determined before and after 24 weeks of octreotide-LAR.

RESULTS

AA exhibited higher beta-cell activity, and insulin and GLP-1 concentrations than Caucasians. Octreotide-LAR suppressed the insulin and GLP-1 levels in both groups.

Racial differences in glucagon-like peptide-1 (GLP-1) concentrations and insulin dynamics during oral glucose tolerance test in obese subjects

Obese African-American (AA) subjects have higher resting and stimulated insulin concentrations than obese Caucasians (C), which could not be explained by the severity of obesity or the degree of insulin sensitivity. We investigated whether differences in glucagon-like peptide-1 (GLP-1), the most potent incretin that regulates insulin secretion, might explain racial differences in insulin response. Accordingly, we measured fasting and stimulated glucose, insulin, and GLP-1 levels during a 3-h oral glucose tolerance test (OGTT) in 26 obese C (age 38+/-2 y, body mass index 44+/-1 kg/m(2)) and 16 obese AA (age 36+/-2 y, BMI 46+/-2 kg/m(2)) subjects. Corrected insulin response (CIR(30)), a measure of beta-cell activity, whole body insulin sensitivity index (WBISI), and area under the curve (AUC) for insulin, GLP-1, and C-peptide/insulin ratio were computed from the OGTT. Glucose levels, fasting and during the OGTT, were similar between racial groups; 32% of the C and 31% of the AA subjects had impaired glucose tolerance. With a similar WBISI, AAs had significantly higher CIR(30) (2.3+/-0.4 vs 1.01+/-0.1), insulin response (IAUC: 23 974+/-4828 vs 14 478+/-1463), and lower insulin clearance (0.07+/-0.01 vs 0.11+/-0.01) than C (all, P<0.01). Obese AAs also had higher fasting GLP-1 (6.7+/-2.5 vs 4.5+/-1.1) and GLP-1AUC (1174.7+/-412 vs 822.4+/-191) than C (both, P<0.02). Our results indicate that obese AAs had higher concentrations of GLP-1 both at fasting and during the OGTT than obese C. The increased GLP-1 concentration could explain the greater insulin concentration and the increased prevalence of hyperinsulinemia-associated disorders including obesity and type 2 diabetes in AAs.

Suppression of insulin secretion is associated with weight loss and altered macronutrient intake and preference in a subset of obese adults

PURPOSE

Hyperinsulinemia is a common feature of many obesity syndromes. We investigated whether suppression of insulin secretion, without dietary or exercise intervention, could promote weight loss and alter food intake and preference in obese adults.

METHODS

Suppression of insulin secretion was achieved using octreotide-LAR 40 mg IM q28d for 24 weeks in 44 severely obese adults (89% female, 39% minority). Oral glucose tolerance testing was performed before and after treatment, indices of beta-cell activity (CIRgp), insulin sensitivity (CISI), and clearance (CP/I AUC) were computed, and leptin levels, 3-day food records and carbohydrate-craving measurements were obtained. DEXA evaluations were performed pre- and post-therapy in an evaluable subgroup.

RESULTS

For the entire cohort, significant insulin suppression was achieved with simultaneous improvements in insulin sensitivity, weight loss, and body mass index (BMI). Leptin, fat mass, total caloric intake, and carbohydrate craving significantly decreased. When grouped by BMI response, high responders (HR; DeltaBMI<-3 kg/m(2)) and low responders (LR; DeltaBMI between -3 and -0.5) exhibited higher suppression of CIRgp and IAUC than nonresponders (NR; DeltaBMI-0.5). CISI improved and significant declines in leptin and fat mass occurred only in HR and LR. Conversely, both leptin and fat mass increased in NR. Carbohydrate intake was markedly suppressed in HR only, while carbohydrate-craving scores decreased in HR and LR. For the entire cohort, DeltaBMI correlated with DeltaCISI, Deltafat mass, and Deltaleptin. DeltaFat mass also correlated with DeltaIAUC and DeltaCISI.

CONCLUSIONS

In a subcohort of obese adults, suppression of insulin secretion was associated with loss of body weight and fat mass and with concomitant modulation of caloric intake and macronutrient preference.

The neuroendocrinology of obesity

The regulation of energy balance is enormously complex, with numerous genetic, hormonal, neural/behavioral, and societal influences. Although the current epidemic of obesity has its underpinnings in the changes in culture during the last half century, the role of the neuroendocrine system in the genesis of obesity is physiologically and therapeutically unavoidable. Increased understanding of this system has suggested organic etiologies (and therapies) for some rare and not-so-rare forms of obesity. With so many inputs, it is not implausible that dysfunction of other parts of this feedback system will be found to explain other forms of obesity in the future. Fortunately or unfortunately, diet and exercise remain the mainstays of obesity therapy. Most diet-exercise programs result in an acute 11-kg weight loss in adults; the question is whether it can be sustained without significant long-term behavior modification. In the European Sibutramine Trial of Obesity Reduction and Maintenance (STORM), 42% of treated patients dropped out; of those remaining, 77% of subjects lost more than 5% of initial body weight, but only 43% of these individuals maintained greater than 80% of this loss over 2 years. Could there be an organic component in persons who do not respond? Obesity pharmacotherapies sometimes have beneficial acute effects, but these effects are impermanent; discontinuation tends to result in a rebound weight gain, suggesting that the etiology of the obesity is still present. A useful guiding principle is that patients who do not respond to diet and exercise should undergo an initial medical evaluation, including assessments of birth weight, past medical history, weight history, family history, diet, exercise, and fasting insulin and thyroid levels. As the nosology of obesity improves, diagnostic efficiency and therapeutic success should increase, leading to a decrease in associated morbidity, mortality, and socioeconomic ramifications.

The neuroendocrinology of childhood obesity

The regulation of energy balance is enormously complex, with numerous genetic, hormonal, neural and behavioral, and societal influences. Although the current epidemic of obesity clearly has its underpinnings in the changes in culture during the past half-century (see other articles in this issue), the role of the neuroendocrine system in the genesis of obesity, as described in this article, is physiologically and therapeutically unavoidable. An understanding of this system has suggested organic causes (and therapies) for some rare and not-so-rare forms of obesity. With so many inputs, it is not far-fetched to assume that dysfunction of other parts of this feedback system will be found to explain other forms of obesity in the future. What does this mean for obese children entering the pediatrician's office? Fortunately or unfortunately, diet and exercise are the mainstays of obesity therapy for children and adults. Most diet-exercise programs result in an acute 11-kg weight loss in adults; the question is whether it can be sustained without significant long-term behavioral modification. For instance, the European Sibutramine Trial of Obesity Reduction and Maintenance trial showed that 42% of treated subjects drop out; of those remaining, 77% of subjects lost more than 5% of initial body weight, but only 43% of those maintained more than 80% of this over 2 years. Could there be an organic component in those who do not respond? Of course, obesity pharmacotherapies sometimes have beneficial acute effects, but these drugs work for only as long as they are consumed; discontinuation tends to result in a "rebound" weight gain, suggesting that the cause of the obesity is still present. Furthermore, in 2001, there are no obesity drugs approved for children. A useful guiding principle is that children deserve at the minimum an initial medical evaluation, including birth weight, medical history, family history, dietary evaluation, and exercise assessment. Perhaps the most important feature that can distinguish "organic" from "behavioral" weight gain in childhood is the age of the "adiposity rebound." The Centers for Disease Control and Prevention now supplies BMI charts for boys and girls at www.cdc.gov/growthcharts. Plotting of the BMI versus age allows pediatricians to determine the age at which the BMI starts to increase (mean, 5.5 years). The earlier the adiposity rebound, the more likely the child will be obese as an adult, and the more likely that an organic cause can be determined. In such patients, thyroid levels and fasting insulin and leptin levels should be measured. An initial attempt at diet and exercise is essential; patients who do not respond with BMI stabilization should be investigated for a more ominous cause of their obesity. As the nosology of obesity improves, pediatricians will be able to increase the diagnostic efficiency and therapeutic success of this unfortunate, debilitating, and expensive epidemic.

Bone mineral decrements in survivors of childhood acute lymphoblastic leukemia: frequency of occurrence and risk factors for their development

We assessed the clinical and treatment factors that predispose survivors of childhood acute lymphoblastic leukemia (ALL) to low bone mineral density (BMD). Using quantitative computed tomography, we determined the frequency of low BMD (defined as >1.645 standard deviations (SD) below the mean) in leukemia survivors treated with multiagent chemotherapy including prednisone and antimetabolite. All participants had completed therapy at least 4 years earlier, remained in continuous complete remission, and had no second malignancies. We statistically correlated BMD results with patient characteristics and treatment histories. Among 141 survivors (median age, 15.9 years; median time after diagnosis, 11.5 years), median BMD z score was -0.78 SD (range, -3.23 to 3.61 SDs). Thirty participants (21%; 95% confidence interval, 15% to 29%) had abnormally low BMD, a proportion significantly (P < 0.0001) greater than the expected 5% in normal populations. Risk factors for BMD decrements included male sex (P = 0.038), Caucasian race (P < 0.0001), and cranial irradiation (P= 0.0087). BMD inversely correlated with cranial irradiation dose. BMD z scores of patients who received higher doses of antimetabolites were lower than those of other patients. Childhood ALL survivors are at risk to have low BMD, especially males, Caucasians, and those who received cranial irradiation.

Diagnosis of ACTH deficiency. Comparison of overnight metyrapone test to either low-dose or high-dose ACTH test

Test sensitivity and accuracy of 250 microg/m(2) ACTH test, 1 microg/m(2) ACTH test, and overnight metyrapone test were evaluated in 158 children at risk for ACTH deficiency. Of 38 given high-dose ACTH, 20 had normal responses to metyrapone and to high-dose ACTH. 14 had low response to metyrapone; of these only 2 had low cortisol response (<550 nmol/l) to high-dose ACTH. Of 120 given low-dose ACTH, 64 had normal responses to metyrapone and to low-dose ACTH. All 24 with low metyrapone response had low or borderline response to low-dose ACTH. The remaining children had an inconclusive metyrapone response. In conclusion, high-dose ACTH misses most diagnoses of ACTH deficiency (21% sensitivity, 100% specificity, 63% accuracy). In contrast, the low dose ACTH test accurately diagnoses 90% of patients with ACTH deficiency (100% sensitivity, 68% specificity). The low-dose ACTH test can serve as an accurate and practical screening test for adequacy of ACTH reserve.

Diagnosis of hidden central hypothyroidism in survivors of childhood cancer

To determine how often central hypothyroidism remains undetected by routine out-patient tests of thyroid hormone, we studied 208 pediatric cancer survivors referred for evaluation because of signs of subtle hypothyroidism or hypopituitarism. Of the 208 (68 females and 140 males), 110 had brain tumors, 14 had other head/neck tumors, 11 had solid tumors remote from head and neck, and 73 had leukemia. Patients were evaluated 1-16 yr (mean, 6.1+/-4.1 yr) after tumor diagnosis. The nocturnal TSH surge and response to TRH were measured. Of 160 patients with free T4 in lowest third of normal, 34% had central hypothyroidism (blunted TSH surge or low/delayed TSH peak or delayed TSH decline after TRH); 9% had central hypothyroidism with mild TSH elevation (mixed hypothyroidism). Another 16% had mild primary hypothyroidism (TSH, 5-15 mU/L). Of 48 with free T4 in the upper two thirds of normal, 14% had central hypothyroidism; 17% had mild primary hypothyroidism. Incidence of central, mixed, and mild primary hypothyroidism 10 yr after tumor diagnosis was significantly related to total cranial radiation dose (P < 0.0001). Of 62 patients with central hypothyroidism, 34% had not developed GH deficiency. TSH surge identified 71%, and response to TRH identified 60% of those with central hypothyroidism. More than half of the slowly growing patients who have received cranial or craniospinal radiation for childhood cancer develop subtle hypothyroidism. In our study group, 92% of patients with central hypothyroidism and 27% with mixed hypothyroidism would have remained undiagnosed using baseline thyroid function tests alone. Both TSH surge and response to TRH must be evaluated to identify all of these patients.

Hypothalamic obesity caused by cranial insult in children: altered glucose and insulin dynamics and reversal by a somatostatin agonist

OBJECTIVE

Hypothalamic obesity is a rare sequela of cranial insult, for which pathogenesis and treatment remain obscure. In rodents ventromedial hypothalamic damage causes hyperphagia, obesity, hyperinsulinism, and insulin resistance. Reduction of insulin secretion in humans may attenuate weight gain.

METHODS

Eight children with intractable obesity after therapy for leukemia or brain tumors underwent oral glucose tolerance testing (OGTT) with simultaneous insulin levels before and after treatment with octreotide for 6 months.

RESULTS

In comparison with a 6-month pre-study observation period, patients exhibited weight loss (+6.0 +/- 0.7 kg vs -4.8 +/- 1.8 kg; P =.04) and decrease in body mass index (+2.1 +/- 0.3 kg/m(2) vs -2.0 +/- 0.7 kg/m(2); P =.0001). Recall calorie count decreased during the 6 months of treatment (P =. 015). OGTT demonstrated biochemical glucose intolerance in 5 of 8 patients initially and in 2 of 7 at study end, whereas insulin response was decreased (281 +/- 47 microU/mL vs 114 +/- 35 microU/mL; P =.04). Percent weight change correlated with changes in insulin response (r = 0.72, P =.012) and changes in plasma leptin r = 0.76, P =.0004).

CONCLUSIONS

Patients with hypothalamic obesity demonstrate excessive insulin secretion. Octreotide administration promoted weight loss, which correlated with reduction in insulin secretion on OGTT and with reduction in leptin levels. Pre-study biochemical glucose tolerance improved in several patients while they were receiving octreotide. These results suggest that normalization of insulin secretion may be an effective therapeutic strategy in this syndrome.

Papillary thyroid carcinoma: demographics, treatment, and outcome in eleven pediatric patients treated at a single institution

We describe 11 cases (8 females, 3 males) of papillary thyroid carcinoma in children treated at St. Jude Children's Research Hospital over a 33-year period, and review the literature. Ages ranged from 7-25 years (median, 16 years). Six patients had primary papillary thyroid carcinoma. Five patients had secondary papillary thyroid carcinoma after treatment of Hodgkin's disease (n = 2), acute lymphoblastic leukemia (n = 2), and neuroblastoma (n = 1) with chemotherapy and cervical radiation. The typical presentation was either cervical lymphadenopathy or a thyroid mass of short duration. Treatment consisted of thyroidectomy, cervical lymph node dissection, and postoperative thyroid hormone replacement (n = 1), parathyroid reimplantation (n = 1), 131I ablation (n = 4), external-beam irradiation (n = 1), and chemotherapy with doxorubicin (n = 1) or carboplatin and topotecan (n = 1). Nine patients are alive without evidence of disease 3.0-22.4 years from diagnosis. One patient has persistent but stable disease 17.3 years after diagnosis. One patient relapsed with metastatic lung disease 0.3 years after the initial diagnosis. He continues to do well after a brief but unsustained complete radiographic remission of disease to combination chemotherapy with carboplatin and topotecan. Our review supports excellent long-term outcome for primary or secondary papillary thyroid carcinoma in pediatric patients although complications may require close follow-up in a multidisciplinary setting.

In vitro models for the effects of sex hormones on neurons

The results of these two in vitro models share some striking similarities. In both, estrogen was able to induce or promote the formation of either dendrites themselves in hippocampal neurons or dendritic specializations in PC12 neurites, and these specializations were then able to induce interneural interactions. In both models, androgen was able to promote the development of axons that branched frequently, while not directly fostering interneuronal contact. These findings recapitulate in part some of the effects of estrogen and androgen on neurons in vivo and suggest the inherent ability of cells of neural crest origin to respond to these hormones with specific neural morphogenetic programs designed to alter interneuronal communication. In these ways, it seems likely that both sex hormones are acting as neural growth factors in cells that express the appropriate receptor, leading to stereotyped changes in neural growth and pattern formation. Through the examination of such subcellular mechanisms, we hope to further understand the effects of sex hormones on brain development and the ontogeny of behavioral, cognitive, and reproductive differences between the sexes.

Testicular degeneration in three patients with the persistent müllerian duct syndrome

The persistent müllerian duct syndrome, characterized by the presence of uterus and tubes in males, is a familial disorder due to defects of synthesis or action of anti-müllerian hormone, a Sertoli cell glycoprotein responsible for the regression of müllerian derivatives in normal male fetuses. Patients are normally virilized and testicular production of testosterone is normal. Both testes may be cryptorchid; alternatively, one may be descended into the inguinal canal or scrotum, together with the müllerian derivatives, a condition known as "hernia uteri inguinalis". We have recently observed three patients affected by the persistent müllerian duct syndrome who experienced progressive degeneration of testicular tissue. In two, functional testicular tissue was still present some months after birth, but deteriorated progressively later. In one patient, testicular tissue was already absent at birth, but the normal virilization of external genitalia indicated that testicular degeneration must have occurred late during fetal life, after the expected time of regression of male müllerian ducts.

CONCLUSION

The high incidence of degeneration of testicular tissue in the persistent müllerian duct syndrome could be indirectly linked to anatomical abnormalities which could favour testicular torsion, known to induce testicular regression.

The use of glucocorticoids in acute lymphoblastic leukemia of childhood. Molecular, cellular, and clinical considerations

Glucocorticoids have been included in almost all treatment regimens for childhood acute lymphoblastic leukemia for decades. However, optimal agents, doses, and/or schedules have yet to be defined despite extensive clinical application. New data on the pharmacokinetics, pharmacodynamics, and molecular mechanisms of action of glucocorticoids have suggested alternative approaches in ALL. These suggest that prolonged, i.e. 28 day, glucocorticoid therapy may be unnecessary as exposure to glucocorticoid induces down-regulation of glucocorticoid receptors. Dexamethasone may be superior to prednisone in conventional equi-effective doses. Blast sensitivity to glucocorticoids correlates closely with sensitivity to other, putatively non-cross-resisting agents and with outcome after multi-agent therapy, suggesting overlapping mechanisms of action, and focusing attention on the determinants of the threshold for apoptosis. Increasing success in the treatment of childhood acute lymphoblastic leukemia has led to increasing awareness of avascular necrosis of bone as a potentially disabling sequela of glucocorticoid therapy, especially in adolescent and young adult patients.

An in vitro model for the effects of androgen on neurons employing androgen receptor-transfected PC12 cells

Androgen alters neurite outgrowth, synaptic organization, and cell survival in various portions of the brain and spinal cord. However, examination of the specific effects of androgen on neurons in vivo has been difficult. Previously, an in vitro model for the effects of estrogen on neurons was developed and characterized, using an estrogen receptor (ER)-transfected PC12 rat pheochromocytoma cell line. This model demonstrated estrogenic regulation of neurite outgrowth, spine formation, and gap junction formation. Similarly, an in vitro model for the effects of androgen on neurons is now described. Wild-type cells (PC12-WT) were stably transfected with an expression vector coding for the full-length cDNA for the human androgen receptor (AR). Resultant clones were isolated, screened for incorporation of vector and expression of AR mRNA and protein, and analyzed for morphologic responses to androgen. PC12-WT, NE09 (ER-negative, AR-negative), SER8 (ER-positive, AR-negative), and AR8 (ER-negative, AR-positive) cells were exposed to 10 ng/ml nerve growth factor (NGF), along with 0-10(-7) M dihydrotestosterone (DHT) for 2 days. AR8 cells demonstrated an androgen dose-dependent increase in mean neurite length, branch order, and neurite field area, whereas neurite branch segment length and soma area were not affected by androgen. PC12-WT, NE09, and SER8 cells exhibited no alterations in cell morphology with DHT exposure. Because of the synergistic effects of DHT and NGF, the regulation of NGF receptor mRNA by DHT was evaluated; however, no significant induction of either trkA or p75 mRNA expression by androgen was documented. The results suggest that in AR-positive PC12 cells, androgen acts additively with NGF to increase neurite outgrowth; but androgen effects are mediated specifically through branching and arborization. These responses are similar to developmental studies of androgen effects in vivo. Thus, androgen appears to induce an inherent neural morphologic program in AR-containing cells, which increases the receptive field of these cells, increasing the likelihood for interneural communication, although not promoting communication itself. These cell lines will provide a unique in vitro system for studying mechanisms of androgen-neuron interactions.

Sex hormone modulation of neural development in vitro

The sex hormonal milieu during human and primate development is thought to influence adult cognition, perception, and behavior. Similarly in the rat, the neonatal sex hormonal milieu dictates adult behavior, as well as patterns of neural organization within the CNS. Specifically, estrogen and androgen alter neurite outgrowth, neuritic spine development, and synaptogenesis in the limbic system and spinal cord. To examine specific molecular/cellular effects of sex hormones on neurons, in vitro models were developed, using the PC12 cell line. Wild-type cells (PC12-WT) were stably transfected either with an expression vector coding for the human estrogen receptor (ER), androgen receptor (AR), or with a control vector. Resultant clones were isolated, screened for incorporation of vector and expression of ER or AR mRNA and protein, and analyzed for morphologic responses to estrogen and androgen, respectively. PC12-WT, NEO9 (ER-negative, AR-negative), SER8 (ER-positive, AR-negative), and AR8 (ER-negative, AR-positive) cells were exposed to nerve growth factor and graded doses of estradiol or dihydrotestosterone (DHT) for 2 days. In SER8 cells, estradiol led to dose-dependent increases in the frequency of neurite outgrowth, spine development, and interneuritic connectivity. Estradiol increased the frequency of gap junction frequency and length, and functional dye-coupling in SER8 cells. Conversely, in AR8 cells, DHT induced a dose-dependent increase in mean neurite length, branch order, and neuritic field area, while neurite branch segment length and soma area were unaffected. These results suggest that SER8 and AR8 cells in vitro recapitulate various sex hormonal effects on neurons in vivo. Estrogen and androgen appear to induce inherent neural morphologic programs in which androgen increases neurite arborization and the receptive field of individual cells, increasing the likelihood for intercellular communication, while estrogen actually induces this communication, in the form of spines, synapses, and gap junctions. Thus estrogen and androgen act in different but complementary ways to modulate neural development and organization.

An in vitro model for the effects of estrogen on neurons employing estrogen receptor-transfected PC12 cells

Estrogen alters neurite outgrowth, neuritic spine development, and synaptogenesis in estrogen-responsive areas of the rat brain. However, examination of the specific effects of estrogen on neurons in vivo has been difficult. An in vitro model for the effects of estrogen on neurons was developed, using the PC12 rat pheochromocytoma cell line. Wild-type cells (PC12-WT) were stably transfected either with an expression vector coding for the full-length cDNA for the human estrogen receptor (hER), or with a control vector. Resultant clones were isolated, screened for incorporation of vector and expression of ER mRNA and protein, and analyzed for morphologic responses to estrogen. PC12-WT, NEO9 (ER-negative), and SER8 (ER-positive) cells exposed to 100 ng/ml NGF exhibited dose-responsive neurite outgrowth within 2 d by light microscopy (LM). Coadministration of 10(-10) to 10(-9) M estradiol (E2) had minimal effects on neurite outgrowth, neuritic spine development, or interneuritic connections in NEO9 or PC12-WT cells, but in SER8 cells E2 led to additive and dose-dependent increases in neurite outgrowth, spine development, and interneuritic connectivity. Coincubation of SER8 cells with E2 and the antiestrogen ICI 164,384 negated estrogenic effects on spine development and interneuritic connectivity. At the electron microscopic (EM) level, intercellular abutments of NEO9 or PC12-WT cells contained few and rudimentary gap junctions, with no increase by E2. However, SER8 cells exhibited augmented basal frequencies of gap junctions that increased with E2 incubation. Microinjection of Lucifer yellow into PC12-WT and NEO9 cells demonstrated low frequencies of dye coupling and no change with E2, but SER8 cells demonstrated increased dye-coupling frequency with E2 coincubation. The results suggest that SER8 cells recapitulate estrogen effects on neurons in vivo. Estrogen appears to induce an inherent neural morphologic program in estrogen receptor (ER)-containing cells. These three cell lines provide a unique in vitro system for studying mechanisms of estrogen-neuron interactions.

Ontogeny, sex dimorphism, and neonatal sex hormone determination of synapse-associated messenger RNAs in rat brain

Sex hormones influence neurite outgrowth and synaptogenesis in certain hormone-dependent areas of the rat brain during neonatal development. These alterations are thought to mediate changes in brain structure and function between the sexes. Growth-associated protein 43 kDa (GAP-43) gene expression is estrogen-regulated in the adult ventromedial hypothalamus (VMH) and sexually dimorphic (M:F = 1.8:1) in adult cortex (CTX). Such effects intimate hormonal regulation of synaptic plasticity. To investigate the nature of these dimorphisms, the present study examined the ontogeny of expression of mRNAs encoding 3 neural-specific proteins: GAP-43, SCG10, and synaptosomal-associated protein 25 kDa (SNAP-25); and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in the VMH and CTX; and also the effects of altering the neonatal sex hormonal milieu on the development of these adult dimorphisms. Levels of specific mRNAs in VMH and CTX were quantitated by slot-blot hybridization in rats of both sexes at different postnatal ages. To determine the involvement of neonatal sex hormones on the levels of these mRNAs, male neonatal rat pups were treated with an estrogen receptor antagonist or an aromatase inhibitor, and neonatal female pups were treated with testosterone or estrogen prior to slot-blot evaluations in adulthood. In VMH, GAP-43 mRNA levels were high on days P1 and P4 with a 3-fold decrease by day P23; in CTX, GAP-43 mRNA first increased by day P11, then fell to baseline by day P23. In VMH, SCG10 mRNA showed only small increases with time; but in CTX, there was a 5-fold drop from days P4 to P23. In VMH, SNAP-25 mRNA was low and changed only slightly; but in CTX there was a 5-fold increase between days P4 and P60. At birth, there was no sex dimorphism in either VMH or CTX, but the levels of all 3 neural-specific mRNAs were sexually dimorphic in adult CTX (M:F = 1.76 for GAP-43, 1.46 for SCG10, 1.44 for SNAP-25). GAPDH mRNA levels were regulated developmentally in VMH and CTX, but there was no sex dimorphism in either area. In male rats who received either an estrogen antagonist or aromatase inhibitor at birth, the CTX GAP-43 and SNAP-25 mRNA levels fell by 30%, to levels similar to untreated females. Conversely, in female rats, neonatal treatment with either testosterone or estrogen increased GAP-43 and SNAP-25 mRNA levels by about 30%, to levels similar to the untreated adult male. SCG10 levels did not demonstrate neonatal hormonal dependence.(ABSTRACT TRUNCATED AT 400 WORDS)

Estrogenic regulation and sex dimorphism of growth-associated protein 43 kDa (GAP-43) messenger RNA in the rat

In addition to effects on brain protein synthesis, neurotransmitter release, and electrophysiology, estrogens alter neurite outgrowth and synaptogenesis. This study examined in the adult rat the effects of estrogen and sex on the expression of the GAP-43 gene; encoding a phosphoprotein structurally and physiologically linked to these two processes in the rat CNS. Ovariectomized (OVX) rats were injected with vehicle or estrogen, or male and female rats were either gonadectomized or left intact. Brains were dissected to obtain ventromedial hypothalamus (VMH), posterior hypothalamus (PH), or frontal cortex (CTX). Total RNA from these areas were extracted, and slot-blots of equal masses of total RNA were hybridized to 32P-labeled cDNAs for GAP-43 and beta-actin, and also to synthetic poly-dT. Resultant autoradiograms were scanned by laser densitometry, quantitated, and ratios of the gray scale generated by each probe were compared between experimental groups. GAP-43 mRNA expression, when compared to expression of either beta-actin mRNA or total poly(A)-containing RNA (poly(A) RNA), was higher in VMH and PH as compared to CTX. Estrogen treatment of OVX rats resulted in a 48-74% increase in GAP-43 mRNA levels in the VMH--in one experiment, this increase was noted after 2 h of estradiol treatment, and in another after 3 days of estradiol benzoate treatment; but PH and CTX were unaffected by either estrogen regimen. Conversely, ovariectomy of intact rats decreased GAP-43 mRNA expression by 45% in the VMH, but not in the CTX.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential effects of estradiol and 16 alpha-hydroxyestrone on pituitary and preoptic estrogen receptor regulation

16 alpha-Hydroxyestrone (16OHE1), an endogenous metabolite of estradiol (E2), binds to the estrogen receptor (ER) with low affinity, but is estrogenic in various bioassay systems. 16OHE1 binds covalently to the ER in vitro, exhibits prolonged estrogenic bioactivity in vivo, and has been implicated in several estrogen-dependent diseases. This study examined the effects of 13 days of continuous infusion of E2 or 16OHE1 on lordotic behavior, pituitary growth, and ER regulation in the cytosolic and nuclear fractions of the pituitary and preoptic area of both sexes. Finally, simultaneous pituitary nuclear exchange assays and enzyme immunoassays were performed to search for covalent 16OHE1-ER complexes in vivo. E2 induced lordosis and pituitary growth in both sexes, while 16OHE1 was only slightly less effective. While E2 treatment increased nuclear ER concentrations 2-fold vs. control values, it decreased both cytosolic and total (cytosolic plus nuclear) ER concentrations in pituitary and preoptic area by approximately 3-fold vs. control values in both sexes by exchange assay. In contrast, 16OHE1 did not decrease total pituitary ER concentrations and only minimally decreased total preoptic ER concentrations. Simultaneous exchange assay and immunoassay of pituitary nuclear extracts demonstrated proportionate increases in ER levels in female vs. male and in E2-treated vs. 16OHE1-treated rats. The ratios of (ER enzyme immunoassay divided by ER-exchange) for each rat were similar regardless of metabolite administration. The correlation of individual measurements implied that ER localized to the nuclear fraction by either E2 or 16OHE1 retained both exchangeability and immunoassayability to similar extents, but did not support the presence of 16OHE1-ER covalent complexes. The results of this study suggest that 16OHE1 has significant estrogenic bioactivity, as manifest by its effects on lordosis and pituitary growth, but, in contrast to E2, does not decrease pituitary ER concentrations and only minimally decreases preoptic ER concentrations. This property may be important in the proposed pathogenetic action of 16OHE1 in estrogen-dependent disease.

Temporal actions of 16 alpha-hydroxyestrone in the rat: comparisons of lordosis dynamics with other estrogen metabolites and between sexes

16 alpha-Hydroxyesterone (16OHE1), a metabolite of estradiol (E2) and precursor of estriol (E3), binds to the estrogen receptor (ER) with low affinity (3% of E2), but is estrogenic in both in vitro and in vivo systems. This metabolite is able to bind in a non-dissociable manner to the ER. We examined these properties in vivo by assessing the temporal dynamics of estrogen metabolite action in the rat brain, using lordosis score (LS) to manual stimulation as a serial bioassay of estrogen effect. Male and female castrate Fisher rats were implanted with osmotic minipumps containing either vehicle, E2, 16OHE1, or E3. 16OHE1-induced LS was delayed in onset in both sexes relative to E2 and E3. Male LS reached a similar plateau for all metabolites, whereas female LS reached an initial LS plateau similar in amplitude to the male plateau. Over the next several days, female LS increased to reach a secondary plateau of higher amplitude, which persisted until pump removal. Upon pump removal, E2- and E3-stimulated LS fell to baseline quickly in both sexes, whereas 16OHE1-stimulated LS in males demonstrated a prolongation of maximal LS for 6 days following pump removal. These results suggest that 16OHE1 is estrogenic in the brains of both sexes. The delay of onset of LS with 16OHE1 is consistent with its poor ER affinity. Females were able to augment LS with prolonged exposure to all metabolites, while males could not. The ability of 16OHE1 to maintain maximal LS in the male long after its withdrawal is consistent with its ability to bind non-dissociably to the ER and promote prolonged estrogenic activation. However, females do not exhibit this response, suggesting a sex specificity in the dynamics of ligand-receptor action in the rat brain.

Considerations in the quantitative analysis of autoradiograms from 2-dimensional gels

Two-dimensional (2-D) gel electrophoresis has been used in conjunction with autoradiography and computerized optical densitometry for quantitating specific protein synthesis. However, accurate quantitation of 2-D autoradiograms requires the prior assessment of such parameters as linearity, reciprocity, and reproducibility. The present study was performed to determine the contribution of each of these to the dissimilation of beta-emission and autoradiographic density, and of density and protein synthesis. Various aliquot volumes of a single complex protein specimen labeled with 35S-amino acids were subjected to 2-D gel electrophoresis, and these gels were serially exposed at graded intervals. The peak densities and volumes of the 111 visualized spots were used to examine the above parameters. In our computerized scanning system, the peak density is a more accurate and reproducible parameter of optical density than is spot volume. Approximately 30% of the dynamic range of peak density is non-linear; quantitation of spots above or below the linear range leads to inaccuracies in quantitation. In addition, the phenomenon of reciprocity, which states that density is directly proportional to exposure (beta-emission of 35S x time), is shown to fail as aliquot volume, or mass of 35S increases. The implications of reciprocity failure to accurate quantitation are discussed. Finally, the sources of variance in autoradiographic analysis were examined, by assessing the intra-scan, intra-gel run, and inter-gel run coefficients of variation. The results of this study show that autoradiographic densitometry is an effective method for quantitation of 2-D gels, but linearity, reciprocity, and reproducibility must be assessed prior to its experimental use. Restrictions of such use are suggested.

Two-dimensional gel autoradiographic analysis of the acute effects of estradiol on protein synthesis in the female rat ventromedial nucleus in vivo

Estradiol (E2) alters protein synthetic events in the ventromedial nucleus (VMN) of the hypothalamus to promote lordotic behavior in the female rat. This study analyzed the acute changes induced by E2 in proteins synthesized in the VMN in vivo as measured by 35S incorporation into protein, two-dimensional gel electrophoresis, autoradiography, and computerized optical densitometry. Ovariectomized rats received vehicle or E2, Hamilton syringes were placed stereotaxically in the VMN bilaterally, and 0.9 mCi 35S-labeled methionine and cysteine was infused over 1 h. After 6 h, rats were killed, and VMN samples were subjected to isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Resultant gels underwent autoradiography, and the optical density of each of 240 spots was quantitated using a flat-bed laser scanner. Using a quantitation algorithm based on the linearity and reproducibility of the scanner and film, 123 spots were analyzed for changes in optical density and relative mol wt (MW) and isoelectric point (pI) induced by E2. The spot induced most prominently by E2 had a MW of 70K and a pI of 6.0, confirming previous results. Three spots were quantitatively induced by E2: 1) a 47K MW, pI 5.4 phosphoprotein (96% induction); 2) a 45K MW, pI 5.2 protein (72% induction); and 3) a 100K MW, pI 5.5 protein (82% induction). Two spots increased pI with E2: 1) a 110K MW protein increased from pI 5.4 to 5.5; and 2) a 50K MW protein increased from pI 6.3 to 6.4. Under these conditions and using a quantitative algorithm, only a small number of proteins synthesized in the VMN were induced by E2 in vivo. E2 also exerts effects on the posttranslational modification of another select group of proteins. These proteins may subserve at least part of the physiological effect of E2 in the VMN.

Induction of LH hypersecretion in cyclic rats during the afternoon of oestrus by oestrogen in conjunction with progesterone antagonism or opioidergic blockade

The pro-oestrous secretion of progesterone that follows the LH surge in the rat limits the expression of the daily signal for LH surge initiation until the following oestrous cycle. This study explored the role of endogenous opioid peptides in the extinction by progesterone of the signal for the LH surge induced by oestrogen. Intact cyclic rats underwent external jugular venous cannulation on dioestrus, and were allowed to elicit a spontaneous pro-oestrous LH surge. On the afternoon of pro-oestrus, rats received an s.c. injection of oestradiol and an s.c. injection of either oil, 17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)17 alpha-(prop-1-ynyl)oestra-4,9,dien-3-one (RU 486; a synthetic anti-progestin), or N-cyclopropylmethyl-6-desoxy-6-methylene-noroxy-morphone (nalmefene; a long-acting opiate antagonist). Repeat doses of each were administered on the morning of oestrus to maintain increased oestrogen levels, and either progesterone or opioidergic blockade. Plasma was obtained from 13.00 to 19.00 h on oestrus for determination of the concentration of rat LH. Rats treated with oestradiol alone demonstrated consistently low concentrations of LH throughout the afternoon of oestrus. Rats treated with both oestradiol and either RU 486 or nalmefene demonstrated spontaneous augmentations of rat LH concentration during the afternoon of oestrus, which, although of diminished amplitude as compared with that seen in pro-oestrus, were consistent with a reactivation of the LH surge-generating mechanism. Rats treated with nalmefene in the absence of oestradiol were unable to augment LH secretion spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)

Opioidergic modulation of the oestradiol-induced LH surge in the rat: roles of ovarian steroids

Sex steroids convey information on the status of the reproductive system, which the brain is able to integrate to promote ovulation, in the form of the LH surge. The present studies examined the influence of alterations in central opioidergic tone to initiate the LH surge, and the roles of oestradiol and progesterone to effect changes in opioidergic tone, by antagonizing this activity using either naloxone or nalmefene (N-cyclopropylmethyl-6-desoxy-6-methylene-noroxy-morphone), a long-acting mu- and kappa-opiate antagonist. The timing and amplitude of the LH surge was examined in (1) cyclic rats in pro-oestrus and (2) ovariectomized rats with varying doses of oestradiol supplementation. Plasma was obtained hourly through an indwelling intra-atrial catheter between 13.00 and 19.00 h, and later assayed for LH and oestradiol concentrations by radioimmunoassay. Rats treated with either nalmefene or progesterone on pro-oestrus demonstrated similar advances in the time of initiation of the LH surge by 1-2 h compared with control rats. The effects of nalmefene and progesterone were evident within 2 and 3-5 h of their administration respectively. Conversely, rats treated with progesterone on dioestrus demonstrated low pro-oestrous oestradiol levels and abolition of the pro-oestrous LH surge, but continuous naloxone infusion restored the pro-oestrous LH surge, with raised oestradiol concentrations. In ovariectomized rats without oestradiol supplentation, nalmefene alone was able to increase basal LH levels, but unable to facilitate a spontaneous rise in LH amplitude indicative of an LH surge. Supplementation with low doses of oestradiol was itself ineffective in facilitating a spontaneous rise in LH concentration, but nalmefene co-administration significantly potentiated the ability of low doses of oestradiol to induce augmented LH secretion, in addition to advancing the timing of the spontaneous LH rise. Similarly, progesterone co-administration to ovariectomized, oestradiol-primed rats significantly advanced and augmented LH hypersecretion. The results of these experiments are consistent with the concept that central opioidergic systems normally restrain the initiation of the LH surge, and that blocking opiate receptors removes this inhibition. They advance the hypothesis that oestradiol, the essential signal for LH surge induction, has, as one consequence of its action, the time-specific inhibition of hypothalamic opiodergic tone in the afternoon, which would otherwise restrain the LH surge-generating mechanism.(ABSTRACT TRUNCATED AT 400 WORDS)

Ontogeny of gonadotropin secretion in congenital anorchism: sexual dimorphism versus syndrome of gonadal dysgenesis and diagnostic considerations

The hormonal characteristics of anorchism are elevated basal levels of gonadotropins, especially follicle-stimulating hormone and a low concentration of plasma testosterone that fails to increase after the administration of human chorionic gonadotropin. However, little is known about the dynamics of plasma gonadotropin secretion in infants and children with anorchism. We analyzed plasma gonadotropin concentrations and their responses to luteinizing hormone releasing factor, along with plasma testosterone responses to human chorionic gonadotropin, in 9 children with surgically proved bilateral anorchism. Basal concentrations of gonadotropins, especially plasma follicle-stimulating hormone, are elevated above normal during the first 3 to 4 years of life, decrease gradually to normal prepubertal levels and then increase again after age 9 years. This age-dependent diphasic pattern of gonadotropin secretion is comparable to that described previously in patients with the syndrome of gonadal dysgenesis and it is consistent with steroid-independent central nervous system inhibition of pulsatile luteinizing hormone releasing factor secretion during mid childhood. Moreover, a sex difference in follicle-stimulating hormone and luteinizing hormone values was observed; the mean follicle-stimulating hormone and luteinizing hormone concentrations in anorchid boys less than 3 years old were lower than in patients with Turner's syndrome. We suggest that this sex dichotomy is a consequence, at least in part, of the actions of testosterone derived from the fetal testis on the fetal hypothalamus. Luteinizing hormone releasing factor administration to anorchid male subjects resulted in an age-dependent augmented release of gonadotropin, particularly follicle-stimulating hormone. This study emphasizes that the age of the patient must be considered when interpreting basal gonadotropin levels. We also propose that in mid childhood the luteinizing hormone releasing factor test in conjunction with the human chorionic gonadotropin stimulation test is a more accurate hormonal indicator of patients with congenital anorchism than either the human chorionic gonadotropin test or basal gonadotropin concentrations.

Neonatal septicemia due to Pseudomonas aeruginosa

Group B streptococci and Escherichia coli are the most frequently isolated etiologic agents in neonatal septicemia. Neonatal infection that is caused by Pseudomonas aeruginosa is usually late in onset, nosocomial in origin and epidemic in pattern. However, P. aeruginosa must be considered in all neonatal infections, regardless of the age of onset, so that early, appropriate and often lifesaving antibiotic therapy may be instituted.

Effect of growth hormone-releasing factor on growth hormone release in children with radiation-induced growth hormone deficiency

Five male children who received cranial irradiation for extrahypothalamic intracranial neoplasms or leukemia and subsequently developed severe growth hormone (GH) deficiency were challenged with synthetic growth hormone-releasing factor (GRF-44), in an attempt to distinguish hypothalamic from pituitary dysfunction as a cause of their GH deficiency, and to assess the readily releasable GH reserve in the pituitary. In response to a pulse of GRF-44 (5 micrograms/kg intravenously), mean peak GH levels rose to values higher than those evoked by the pharmacologic agents L-dopa or arginine (6.4 +/- 1.3 ng/mL v 1.5 +/- 0.4 ng/mL, P less than .05). The peak GH value occurred at a mean of 26.0 minutes after administration of GRF-44. These responses were similar to those obtained in children with severe GH deficiency due to other etiologies (peak GH 6.3 +/- 1.7 ng/mL, mean 28.0 minutes). In addition, there was a trend toward an inverse relationship between peak GH response to GRF-44 and the postirradiation interval. Prolactin and somatomedin-C levels did not change significantly after the administration of a single dose of GRF-44. The results of this study support the hypothesis that cranial irradiation in children can lead to hypothalamic GRF deficiency secondary to radiation injury of hypothalamic GRF-secreting neurons. This study also lends support to the potential therapeutic usefulness of GRF-44 or an analog for GH deficiency secondary to cranial irradiation.

Effect of growth hormone (GH)-releasing hormone (GRH) on plasma GH in relation to magnitude and duration of GH deficiency in 26 children and adults with isolated GH deficiency or multiple pituitary hormone deficiencies: evidence for hypothalamic GRH deficiency

Synthetic, amidated, 44 amino acid GH-releasing hormone ( GRH -44) was administered iv at a dose of 5 micrograms/kg to 20 patients with severe GH deficiency (GHD), 6 children and adolescents with partial GHD, and 6 non-GH deficient ( NGHD ) children and adolescents. The 17 patients with severe GHD that responded to GRH -44 had lower peak concentrations of plasma GH than the NGHD individuals (5.0 +/- 1.2 (SEM) vs. 27.2 +/- 3.5 ng/ml; P less than 0.0001). The children and adolescents with severe GHD tended to have higher peak GH responses to GRH -44 than the GHD adults (6.9 +/- 1.7 vs. 2.4 +/- 0.3 ng/ml) although the difference was not significant. The peak GH concentration was attained earlier in the GHD children and adolescents than in the GHD adults (28 +/- 4.7 vs. 69.3 +/- 13 min, P less than 0.004). There was a negative correlation between chronological age and peak plasma GH response to GRH in the children and adolescents with severe GHD (r = -0.758, P less than 0.02). Children and adolescents with partial GHD had a higher mean peak concentration of plasma GH (13. 1 +/- 1.8 ng/ml) than the children, adolescents, and adults with severe GHD (P less than 0.04), but one lower than the NGHD children and adolescents (P less than 0.05). In both severe and partial GHD the GH response to GRH was greater than that elicited by standard pharmacological tests. Serum somatomedin-C did not increase after a single pulse of GRH -44 in the 12 GHD patients studied. PRL increased minimally 30 min after 5 micrograms/kg iv GRH -44 in patients with multiple hypothalamic-pituitary hormone deficiencies but not in patients with isolated GHD or in NGHD individuals. The GH responses to GRH suggest that the majority of patients with isolated GHD as well as those with multiple hypothalamic-pituitary hormone deficiencies have deficiency of hypothalamic GRH . Lack of a GH response to a single pulse of GRH does not exclude GRH deficiency as priming of the somatotrope with multiple pulses of GRH may be necessary to rule out a hypothalamic defect in the nonresponders. The results of this study support the potential usefulness of GRH or its analogs in the diagnosis and treatment of selected patients with disorders of GH secretion.