Search

* Abbreviations: FDA — : US Food and Drug Administration RCT — : randomized controlled trial T2DM — : type 2 diabetes mellitus Childhood obesity has steadily become a contemporary epidemic with serious public health implications.1 Approximately 70% of children with obesity will remain obese in adulthood.2 Obesity is a risk factor for development of atherosclerosis and type 2 diabetes mellitus (T2DM),3 and its prevention and management represents a priority for pediatric primary care providers. This underscores the need for evidence-based interventions for children and adolescents with obesity, including pharmacotherapy.4 Metformin is US Food and Drug Administration (FDA) approved for use in children 10 years of age and older with T2DM and has been used off label to achieve weight loss in children. In the current issue of Pediatrics , Masarwa et al5 present a systematic review of the safety and efficacy of metformin use from randomized controlled trials (RCTs) in children and adolescents. The authors demonstrated that metformin therapy resulted in modest benefits in reduction of BMI in those with obesity. Among the 14 RCTs in which BMI was reported, metformin was modestly efficacious at decreasing BMI (range of mean changes: −2.70 to 1.30) compared with a placebo (−1.12 to 1.90). As pointed out by the authors, the results across the studies were heterogeneous, with 11 RCTs suggesting that it decreased BMI, whereas 3 RCTs revealed an increase in BMI. Among the 7 RCTs in which a BMI z score was reported, metformin consistently resulted in a decrease … Address correspondence to Vandana Raman, MD, Division of Endocrinology, Department of Pediatrics, University of Utah School of Medicine, 81 N Mario Capecchi Dr, Salt Lake City, UT 84113. E-mail: vana.raman{at}hsc.utah.edu

The study examined in adolescents with type 1 diabetes whether higher intelligence was predictive of better subsequent metabolic control through better self-control. Two-hundred fifty two adolescents with type 1 diabetes completed an intelligence test and a measure of self-control at baseline. HbA1c was gathered from medical records at baseline and six months later. A path model revealed that adolescent intelligence at Time 1 was associated with changes in HbA1c from Time 1 to Time 2 through adolescents’ higher self-control. Higher intelligence may be a resource for the application of self-regulatory skills during adolescence that facilitate metabolic control.

To predict trajectories of metabolic control across adolescence from parental involvement and adolescent psychosocial maturity, and to link metabolic control trajectories to health care utilization.Two hundred fifty-two adolescents (M age at study initiation = 12.5 years, SD = 1.5, range = 10-14 years) with type 1 diabetes (54.4% female, 92.8% Caucasian, length of diagnosis M = 4.7 years, SD = 3.0, range = 1-12 years) participated in a 2-year longitudinal study. Metabolic control was gathered from medical records every 3 months. Adolescents completed measures of self-reliance (functional autonomy and extreme peer orientation), self-control (self-control and externalizing behavior), and parental involvement in diabetes care (acceptance, monitoring, and frequency of help). At the end of the study, mothers reported health care utilization (diabetes-related emergency room visits and hospitalizations) over the past 6 months.Latent class growth analyses indicated two distinct trajectories of metabolic control across adolescence: moderate control with slight deterioration (92% of the sample; average HbA1c = 8.18%) and poor control with rapid deterioration (8% of the sample; average HbA1c of 12.09%). Adolescents with poor and rapidly deteriorating metabolic control reported lower paternal monitoring and frequency of help with diabetes management, lower functional autonomy, and lower self-control than others. Those with poor and rapidly deteriorating metabolic control were 6.4 times more likely to report diabetes-related emergency room visits, and 9.3 times more likely to report diabetes-related hospitalizations near the end of the study.Parental involvement and adolescents' psychosocial maturity predict patterns of deteriorating metabolic control across adolescence and could be targeted for intervention.

Objectives To examine pump duration associations with adolescents’ metabolic control and whether parental involvement moderated this association. Methods This study used a cross-sectional sample of 10- to 14-year-olds with diabetes (N = 252, 53.6% female) and parents’ reported parental involvement; HbA1c was obtained from medical records. Half (50.8%) were on an insulin pump (continuous subcutaneous insulin infusion, CSII), with the remainder prescribed multiple daily injections (MDI). Results Adolescents on CSII displayed better HbA1c than those on MDI. A curvilinear association revealed that participants on CSII for

The authors investigated whether parental perceptions of adolescent efficacy are colored by parental negative affect and are associated with adolescents' self-perceptions of efficacy for diabetes management. Adolescents (n = 183, M age = 12.53) with Type 1 diabetes and their mothers and fathers separately reported perceptions of adolescents' efficacy for diabetes management and parents reported their own negative affect (depressed mood and trait anxiety). glycosolated hemoglobin (HbA1c) levels were obtained from medical records. The results indicated that parental negative affect was associated with parental perceptions of poorer adolescent efficacy beyond the association of HbA1c scores. The relationship between fathers' negative affect and adolescents' self-efficacy was mediated by fathers' perceptions of adolescent efficacy. The results suggest that parental negative affect may negatively color their views of adolescents' efficacy and, in the case of fathers' beliefs, may relate to adolescent self-efficacy. Parental negative affect should be considered when evaluating perceptions of adolescents' efficacy.

Objectives To examine how perceptions of parental responsibility for diabetes management are associated with age, pubertal status, adolescents’ self-efficacy, and parental perceptions of adolescents’ efficacy, and if parental responsibility is associated with better metabolic control as a function of adolescents’ self-efficacy and parental perceptions of adolescents’ efficacy. Methods Questionnaires assessing parental responsibility, pubertal status, adolescents’ self-efficacy, and parental perceptions of adolescents’ efficacy were given to 185 adolescents with type 1 diabetes, 185 mothers, and 145 fathers. Results Greater parental responsibility was negatively associated with age, perceptions of pubertal status, and efficacy for all reporters. Interactions between parental responsibility and parental perceptions of adolescents’ efficacy indicated that parental responsibility was associated with better metabolic control when adolescents were perceived to have lower efficacy. Conclusions Adolescents’ and parents’ perceptions of parental responsibility are related to multiple factors. Metabolic control is best when high parental responsibility is maintained among adolescents with lower efficacy.

Maladaptive eating attitudes and behaviors are common in adolescent females with Type 1 Diabetes Mellitus (T1DM). This research assessed potential pathways through which individual and familial factors relate to treatment adherence and glycemic control. Seventy-five females with T1DM (aged 11—17 years) and their mothers completed questionnaires regarding communication, diabetes management, and eating attitudes and behaviors. Hierarchical regression analyses found that body image dissatisfaction moderates the relationship between negative communication and maladaptive eating attitudes and behaviors. Treatment adherence mediates the relationship between maladaptive eating attitudes and behaviors and glycemic control. None of the participants endorsed omitting insulin for the purposes of weight management. This study highlights the need to address familial and individual factors along with treatment adherence within this population.

Ghrelin stimulates both appetite and secretion of growth hormone (GH). We hypothesized that fasting should increase ghrelin, thereby increasing GH concentrations in obesity. Eight obese girls underwent a 48-h fast, receiving 25% of calories for ideal body weight. Blood was obtained every 15 min for the last 24 h of the fast. Four months later, six obese girls had blood obtained in the fed state. Two additional obese and five lean girls had blood obtained in the fed state. Ghrelin was determined in 3-h pools. Mean ghrelin concentrations were 0.41 +/- 0.03 ng/mL for lean girls and 0.16 +/- 0.01 ng/mL in obese fed girls (p0.0001). Lean fed girls had diurnal variation of ghrelin whereas obese fed girls did not. Fasting neither increased ghrelin (0.18 +/- 0.01 ng/mL) nor restored diurnal variation. Ghrelin concentrations were related to the body mass index (BMI) SD score (SDS) (r = 0.45, p = 0.005). For the six obese girls who participated in both fasting and fed studies, change in mean ghrelin concentration between studies was related to change in BMI SDS but not fed or fasting state. Ghrelin concentrations are, thus, a function of BMI rather than feeding status in obese girls.

Peripubertal obesity is associated with abnormal sex steroid concentrations, but the timing of onset and degree of these abnormalities remain unclear.The objective of the study was to assess the degree of hyperandrogenemia across puberty in obese girls and assess overnight sex steroid changes in Tanner stage 1-3 girls.This was a cross-sectional analysis.The study was conducted at general clinical research centers.Thirty normal-weight (body mass index for age85%) and 74 obese (body mass index for ageor= 95%) peripubertal girls.Blood samples (circa 0500-0700 h) were taken while fasting. Samples from the preceding evening (circa 2300 h) were obtained in 23 Tanner 1-3 girls.Hormone concentrations stratified by Tanner stage were measured.Compared with normal-weight girls, mean free testosterone (T) was elevated 2- to 9-fold across puberty in obese girls, whereas fasting insulin was 3-fold elevated in obese Tanner 1-3 girls (P0.05). Mean LH was lower in obese Tanner 1 and 2 girls (P0.05) but not in more mature girls. In a subgroup of normal-weight Tanner 1-3 girls (n = 17), mean progesterone (P) and T increased overnight 2.3- and 2.4-fold, respectively (Por= 0.001). In obese Tanner 1-3 girls (n = 6), evening P and T were elevated, and both tended to increase overnight [mean 1.4- and 1.6-fold, respectively (P = 0.06)].Peripubertal obesity is associated with hyperandrogenemia and hyperinsulinemia throughout puberty, being especially marked shortly before and during early puberty. P and T concentrations in normal-weight Tanner 1-3 girls increase overnight, with similar but less evident changes in obese girls.

Context: Adolescent hyperandrogenemia is considered a forerunner of adult polycystic ovary syndrome, but its etiology remains uncertain. Objective: Our objective was to explore the hypothesis that peripubertal obesity is associated with hyperandrogenemia. Design and Setting: We performed a cross-sectional analysis of data obtained at General Clinical Research Centers. Subjects: Subjects were 41 obese [body mass index (BMI) for age, ≥95%] and 35 normal-weight (BMI for age, Intervention: We used pooled blood samples (∼0500–0700 h; n = 64) while fasting or single morning (fasting) samples (n = 12). Main Outcome Measures: We assessed adiposity and androgen concentrations. Results: BMI correlated with total testosterone (T) (rs = 0.59), SHBG (rs = −0.69), and free T (rs = 0.69); free T was three times as great in obese girls compared with normal-weight girls (P < 0.0001 for all). BMI correlated with insulin (rs = 0.52); both insulin and LH correlated with free T (rs = 0.45 and 0.44, respectively; P < 0.001 for all). When analyzing early pubertal girls (pubertal stages 1–3; n = 36) alone, BMI correlated with total T (rs = 0.65), SHBG (rs = −0.74), and free T (rs = 0.75); free T was five times as great in obese early-pubertal girls (P < 0.001 for all). BMI correlated with insulin (rs = 0.65), and insulin correlated with free T (rs = 0.63, P < 0.01 for both). BMI correlated with free T while simultaneously adjusting for age, pubertal stage, insulin, LH, and dehydroepiandrosterone sulfate. Conclusion: Peripubertal obesity is associated with marked hyperandrogenemia, which is especially pronounced in early puberty.

Microarray technology has become widespread as a means to investigate gene function and metabolic pathways in an organism. A common experiment involves probing, at each of several time points, the gene expression of experimental units subjected to different treatments. Due to the high cost of microarrays, such experiments may be performed without replication and therefore provide a gene expression measurement of only one experimental unit for each combination of treatment and time point. Though an experiment with replication would provide more powerful conclusions, it is still possible to identify differentially expressed genes and to estimate the number of false positives for a specified rejection region when the data is unreplicated. We present a method for identifying differentially expressed genes in this situation that utilizes polynomial regression models to approximate underlying expression patterns. In the first stage of a two-stage permutation approach, we choose a 'best' model at each gene after considering all possible regression models involving treatment effects, terms polynomial in time, and interactions between treatments and polynomial terms. In the second stage, we identify genes whose 'best' model differs significantly from the overall mean model as differentially expressed. The number of expected false positives in the chosen rejection region and the overall proportion of differentially expressed genes are both estimated using a method presented by Storey and Tibshirani (2003). For illustration, the proposed method is applied to an Arabidopsis thaliana microarray data set.

BACKGROUND: Inhibin-B decreases and activin increases FSH secretion in adults. We investigated whether an FSH –inhibin/activin feedback loop exists before or during puberty. METHODS: FSH secretion was stimulated with 10mg/kg leuprolide acetate (GnRH agonist) in 18 girls, ages 1.0– 13.2 years, and 11 boys, ages 8.9– 15.2 years, with variations in pubertal development, and in five normal 9- to 10-year-old girls. Blood, obtained at 0, 0.5, 1, 2, 4, 8, 12, 16, 20 and 24 h after GnRH agonist, was analysed for LH, FSH, activin-A, inhibin-A, inhibin-B, follistatin 288 and estradiol/testosterone. RESULTS: FSH increased within 30 min of GnRH agonist administration with a peak greater in girls than boys (P 5 0.0006). Baseline inhibin-B was greater in boys than girls (P 5 0.01), while baseline activin-A concentrations were greater in girls. GnRH agonist-stimulated FSH increased inhibin-B in girls by 8 h and in boys by 20 h ( P< 0.05), but did not affect activin-A. Inhibin-B increases were seen only in girls older than 5 years. CONCLUSIONS: An inhibin-B– FSH feedback loop exists prior to the onset of puberty in girls older than 5 years. Sex differences in activin-A and inhibin-B concentrations may be responsible for sex differences in serum FSH concentrations.

Various in vitro conditions for culture of ovules prior to extraction and culture of immature embryos of peach [Prunus persica (L.) Batsch] and nectarine [Prunus persica (L.) Batsch var. nucipersica Schneid.] were investigated. Culture vessels consisting of test tubes, petri dishes, and polycarbonate jars were tested along with various types of support and nutrient media. Agar support was superior to liquid media with filter paper supports. Agar produced the largest embryos with 90% to 93% being converted into plants compared to liquid with only 1% to 12% embryo conversion. The best ovule orientation and support was with the micropyle down and pushed halfway into an agar-gelled medium. In experiments two and three, test tubes with vertical ovule orientation (micropyle end of ovule pushed into agar) produced larger embryos, the largest plants and the greatest percentage of embryos that converted into plants (60% and 91%). Petri dish treatments were less successful in embryo conversion than test tubes and polycarbonate jars. The addition of activated charcoal (AC) to an agar-gelled medium produced significantly larger embryos with a similar conversion rate. The addition of an agar-gelled medium to culture vessels reduces preparation time compared to filter paper supports, and placing each ovule within a test tube eliminates cross contamination, making immature embryo culture more successful.

We studied nutrition and GH in eight obese girls, aged 6–11 yr. Blood was sampled every 15 min for 24 h. A 48-h diet providing 25% of assumed caloric needs was imposed, with repeat sampling during the last 24 h. Six nonfasting lean girls were also studied, and their mean GH was 3 times that of the obese girls in the fed state (P = 0.024). Dieting increased mean GH by 60% (P = 0.0028). There was no difference in pulse number for either group, but total secretion for lean girls was 3.9 times greater than that in obese girls during the fed state. With dieting, obese girls increased their total GH secretion by 60% (P = 0.010), but maintained lower total secretion, approximately 40% that of lean girls (P = 0.014). Mean leptin in obese girls in the fed state was 6.2 times greater than mean leptin in lean girls (P = 0.0001), with higher concentrations at night (P < 0.05) and lowering of total mean leptin while dieting. We conclude that in early pubertal obese girls, short-term caloric restriction partially reverses the low GH state that is characteristic of obesity. The change is concomitant with a decrease in leptin and a lessening of circadian differences.

1. Terence A. Joiner, MD, MHSA* 2. Carol Foster, MD† 3. Thomas Shope, MD† 1. 2. *Clinical Assistant Professor. 3. 4. †Associate Professor, Department of Pediatrics and Communicable Diseases, Division of Infectious Diseases, University of Michigan Medical School, Ann Arbor, MI. After completing this article, readers should be able to: 1. Explain the relationship between breastfeeding and vitamin D deficiency. 2. List the clinical findings in rickets. 3. Delineate the clinical finding that can direct physicians toward infants who are at highest risk for rickets. 4. Describe how to evaluate a child for and diagnose vitamin D deficiency rickets. 5. Delineate the management steps that can prevent the occurrence of rickets in children at risk. Contemporary physicians may think of vitamin D deficiency rickets as a disease of the past. In fact, it remains a significant cause of nutritional disease for infants as we enter the 21st century. Unlike iron deficiency anemia, there are no clear recommendations about whether or how to screen children for rickets. The following cases illustrate the many different presentations of rickets. ### PATIENT 1 A 6-month-old African-American female developed cyanosis while breastfeeding followed by two tonic episodes consistent with infantile seizures. History revealed that she was breastfed exclusively, had received no vitamin D supplementation, and was receiving erythromycin for treatment of otitis media. Except for erythematous tympanic membranes, findings on physical examination were normal. Laboratory studies (Table 1⇓ ) demonstrated decreased serum calcium, elevated serum alkaline phosphate, decreased hydroxyvitamin D, and increased dihydroxyvitamin D. Serum creatinine and urea nitrogen values were normal. Radiography revealed osteopenic ribs and flared anterior aspects of the ribs. The distal radial and ulnar metaphyses were cup-shaped, and the distal femoral and proximal tibial metaphyses were slightly widened. View this table: Table 1. Summary of Serum Laboratory Results ### PATIENT 2 A 1-year-old African-American male presented with a 3-day history of cough, fever, and shortness of breath. Chest radiography revealed left pneumonia and a right-sided rib fracture. The infant had been breastfed without vitamin D supplementation. Findings on physical examination included intercostal retractions, a temperature of 38.7°SDC (101.7°SDF), and a weight of 7.65 kg (

Little is known about mechanisms that permit or prevent formation of root nodules in which nitrogen gas (N2) is fixed by rhizobial bacteria in association with nursery crops in the legume family. We tested the hypothesis that two genes associated with the fixation of N2 could be used as markers of nodulation capacity among legumes because they occur only in species that can form functional nodules. The presence of ENOD2 and ENOD12 was tested in genomic DNA from three non-nodulating legumes [Cercis canadensis L. (eastern redbud), Gleditsia triacanthos L. var. inermis Willd. (thornless honeylocust), Gymnocladus dioicus (L.) K. Koch (Kentucky coffeetree)] and two nodulating legumes [Albizia julibrissin Durazz. (silk-tree), Laburnum alpinum (Mill.) Bercht. & Presl. (Scotch laburnum)]. Southern analyses indicated that ENOD2 is present in thornless honeylocust, Kentucky coffeetree, and Scotch laburnum, and that ENOD12 is present in eastern redbud, thornless honeylocust, and Scotch laburnum. These results diversify the group of nodulating legumes in which ENOD2 and ENOD12 have been found and show these genes also occur in legumes considered incapable of nodulation. We conclude that neither gene can be used to screen existing or new leguminous nursery crops for the capacity to form N2-fixing nodules.

Estradiol (E2) negative feedback on LH secretion was examined in 10 pubertal girls, testing the hypothesis that E2 suppresses LH pulse frequency and amplitude through opioid pathways. At 1000 h, a 32-h saline infusion was given, followed 1 week later by an E2 infusion at 13.8 nmol/m2·h. During both infusions, four iv boluses of saline were given hourly beginning at 1200 h, and four naloxone iv boluses (0.1 mg/kg each) were given hourly beginning at 1200 h on the following day. Blood was obtained every 15 min for LH determination and every 60 min for E2 determination from 1200 h to the end of the infusion. E2 infusion increased the mean serum E2 concentration from 44 ± 17 to 112 ± 26 pmol/L (P < 0.01). The mean LH concentration between 2200–1200 h decreased from 3.19 ± 0.89 to 1.99 ± 0.65 IU/L (P = 0.014), and LH pulse amplitude decreased from 3.4 ± 0.6 to 2.6 ± 0.5 IU/L (P = 0.0076). Although there were 1.2 fewer pulses during E2 infusion compared to saline infusion, differences did not reach significance...

Among subfamilies in the Fabaceae, the capacity to form root nodules is most common in the Papilionoideae. Yet nodules have never been observed on species of Cladrastis, and there are conflicting reports of the capacity of species in the genus Styphnolobium to nodulate. Our objectives were to evaluate Styphnolobium japonicum (formerly Sophora japonica) and Cladrastis kentukea for the capacity to nodulate and to characterize any isolated rhizobia. N-deficient plants were inoculated with rhizobia chosen for their low host specificity or for their symbiotic potential with indigenous and introduced trees and shrubs of Sophora species in Hawaii, Japan and China. Soil samples from the root zones of mature S. japonicum, C. kentukea and other woody legumes, introduced or indigenous to Hawaii, Japan, China and the continental USA, also were used as inocula. Inoculation did not elicit nodulation of C. kentukea or S. japonicum, despite that N concentrations of shoots of S. japonicum (1.6%) and C. kentukea (1.5%) fell below the highest shoot N percentage that previously was associated with well-nodulated plants of Maackia amurensis (1.8%). In addition to these analyses, rhizobia were isolated from nodules on the roots of a tree reported to us as S. japonicum. Nine of the 10 isolates selected as representatives of similarity groups were capable of nodulating M. amurensis, which led to the identification of the putative S. japonicum as Maackia floribunda. We also found that broad-range Bradyrhizobium USDA 6, USDA 3384 and USDA 3456 induce nodules on R. pseudoacacia and M. amurensis, which were used as control species during inoculation trials with S. japonicum and C. kentukea. Our conclusion that S. japonicum and C. kentukea lack the capacity to nodulate is based on the most thorough analysis of the nodulation capacity of these species to date. Previous reports of nodulation of S. japonicum may have been due to inaccurate plant or nodule identification.

Acceleration of linear growth during puberty is associated with increased GH secretion, although the relationship between growth and GH is complex. As GH exists as a family of isoforms, some of which may not be identified by immunoassay, there may be alterations in isoform secretion during pubertal maturation that result in increased growth. The changes in serum immunoreactive and bioactive GH concentrations across pubertal maturation were determined in 30 boys, aged 6.5–19.3 yr, with idiopathic short stature or constitutional delay of adolescence. Data were grouped as follows: 1) 6 prepubertal boys with bone age 7 yr or less; 2) 5 prepubertal boys with bone age of more than 7 yr; 3) 10 boys in early puberty; 4) 9 boys with mid- to late puberty. Blood was obtained every 20 min from 2000–0800 h. An equal aliquot of each serum sample was pooled for determination of GH by bio- and immunoassays. The mean serum immunoreactive GH concentration increased from 2.1 ± 0.3, 1.8 ± 0.3, and 2.9 ± 0.5 μg/L in groups 1, 2, and 3, respectively, to a peak of 4.6 ± 0.7 μg/L in group 4 (P < 0.05 vs. groups 1–3). The mean serum GH bioactivity was 48 ± 13 μg/L in group 1 and declined to 39 ± 8 and 31 ± 3 μg/L in groups 2 and 3, increasing to a maximum of 64 ± 15 μg/L in group 4 (P < 0.05 vs. group 3). The ratio of bioactive to immunoreactive GH suggests that the biopotencies of secreted isoforms do not increase during pubertal maturation. The role of E2 in increasing GH secretion was characterized in 8 additional early pubertal boys. Each boy received a saline infusion from 1000–0800 h, followed 1 week later by an infusion of E2 at 4.6 nmol/m2·h. Blood was obtained every 15 min from 2200–0800 h for GH and LH and every 60 min for E2 and testosterone. An equal aliquot of each overnight serum sample was pooled for insulin-like growth factor I (IGF-I) and GH by immuno- and bioassays. The mean serum LH concentration decreased from 5.0 ± 0.9 to 2.3 ± 0.6 IU/L (P < 0.01), and the E2 concentration increased from 22 ± 4 to 81 ± 26 pmol/L (P < 0.01) during saline and E2 infusions, respectively. Mean serum GH concentrations as measured by immunoassay were similar during both infusions (6.6 ± 1.4 vs. 9.7 ± 2.1 μg/L; saline vs. E2 infusion, respectively). In contrast, the mean serum GH concentration, as measured by bioassay, decreased from 48 ± 10 μg/L during saline infusion to 16± 3 μg/L during E2 infusion (P < 0.05). The mean serum IGF-I concentration also decreased significantly from 116 ± 17 to 93 ± 15 μg/L (saline vs. E2 infusion, respectively; P < 0.05). Thus, although mean overnight serum GH concentrations increase in late puberty, whether measured by immuno- or bioassay, an acute increase in E2 produces an acute decline in serum GH bioactivity and a lesser decline in the serum IGF-I concentration. These unexpected changes indicate that E2 may affect pubertal growth and GH secretion in a complex or biphasic manner depending on the context in which it is administered.

Point mutations in the luteinizing hormone/human chorionic gonadotropin (LH/hCG) receptor have been shown to cause constitutive activation which results in precocious puberty in affected males. We introduced one of these mutations, Asp-556 → Gly, into the rat LH/hCG receptor and demonstrated that the mutant receptor constitutively activated adenylate cyclase in transfected 293 T cells. The cell surface expression of the mutant receptor was lower than that of the wild type receptor. Pulse-chase studies showed that the 73-kDa precursor of both the mutant and wild type receptors was synthesized at comparable efficiencies. However, post-translational processing of the mutant receptor to the mature 92-kDa form, which has N-linked complex type oligosaccharide chains, was impaired. Sensitivity of the mutant receptor to peptide-N-glycanase F and endoglycosidase H, and insensitivity to sialidase indicated that the 73-kDa species represents the high mannose form that has not yet been trafficked through the medial and trans Golgi. Additionally, although the wild type receptor was palmitoylated, the mutant receptor was not. Although the high mannose 73-kDa species is capable of binding LH/hCG, our results show that post-translational processing in the Golgi is required for the mature 92-kDa receptor to reach the cell surface.

To determine: (1) the frequency of risky behaviors (alcohol and other drug use, smoking cigarettes, smokeless tobacco use, and unprotected intercourse); (2) the perception of general risks and diabetes-related risks from risky behaviors; (3) if perception of risk is related to engaging in risky behaviors; and (4) if perception of general risks and diabetes-related risks are influenced by age, gender, or race in adolescents with insulin dependent diabetes mellitus (IDDM). Decreasing risky behaviors in youth with IDDM is important because of their increased vulnerability to specific disease related physiologic and pathologic changes.A descriptive, cross-sectional design was used. Data on risky behavior and perception of risk were obtained by self-report during a regularly scheduled clinic visit. One hundred and fifty-five adolescents between ages of 10-20 years participated. Correlational and student's t-test analyses were used to test relationships and group differences (age, race, gender).Thirty-nine percent of the sample reported alcohol use, 34% reported smoking cigarettes, 8% reported smokeless tobacco use, 10% reported drug use, and 29% reported unprotected intercourse. Perception of risk to peers from these behaviors was significantly higher (t = 8.1, df 153; p.001) than risk to self. Females reported significantly lower (t = 3.08, df 52; p.002) risk to self than males. There was no difference in perception of risk between youth who reported participating in risky behaviors (N = 38%) and those who did not (62%). Not surprisingly, the frequency of risky behavior increased with age (F = 15.46; p.001).Compared to community samples of middle school children, our sample had lower rates for most risky behaviors. As with community samples, the physical risks were known and perceived to be higher for peers than self. Perception of risk was not related to self-reports of risky behaviors. The lower rate of risky behaviors might reflect the success of educational efforts directed toward diabetes management or may be due to later initiation of behaviors, especially if personal social development is delayed. Additional research is indicated in order to understand the timing and trajectory of risky behavior and whether or not perception of risk deters youth with IDDM from engaging in risky behavior.

We have recently developed a new bioassay for growth hormone (GH) in serum, which is based on the ability of GH to suppress glucose use in cultured murine adipocytes. We tested the hypothesis that bioactive GH (B-GH) concentrations would correlate better with the GH-dependent peptides, IGF-I, and IGF-binding protein-3 (IGFBP-3) than would GH determined by conventional RIA (RIA-GH). Twenty-five girls with Turner's syndrome were studied. The subjects had ages ranging from 4.8 to 15.9 y and height SD from the mean (SD score) ranging from -0.77 to -5.67. Blood samples were obtained every 15 or 20 min for 12 h overnight. For each girl, an equal aliquot of each overnight sample was pooled for determination of B-GH, RIA-GH, IGF-I, IGFBP-3, LH, FSH, and estradiol. Measurable estradiol concentrations were present in six girls and were sufficient to suppress gonadotropin concentrations in two girls, but they did not alter B-GH, RIA-GH, IGF-I, and IGFBP-3 concentrations compared with the age-matched girls without measurable estradiol concentrations. Hence, data for all girls were combined for subsequent regression analyses. RIA-GH did not correlate significantly with B-GH, IGF-I, or IGFBP-3. B-GH exhibited a significant correlation with IGF-I (r = 0.407, p < 0.05), and the correlation with IGFBP-3 was better than that for RIA-GH (r = 0.355 versus 0.064, B-GH and RIA-GH, respectively). None of the B-GH, RIA-GH, IGF-I, or IGFBP-3 concentrations had a significant correlation with height SD score or height velocity SD score.(ABSTRACT TRUNCATED AT 250 WORDS)

In its classical form, McCune-Albright syndrome is a triad of cafe-au-lait skin pigmentation, fibrous dysplasia of bone, and sexual precocity. The endocrinopathy of McCune-Albright syndrome is more extensive, however, and patients may also have hyperfunction of thyroid, adrenal, and pituitary tissues, and/or hypophosphatemia. The recent appreciation that all these tissues share hormone-mediated activation of adenylate cyclase has resulted in the identification of a mutation of the α subunit of the G protein that stimulates cAMP formation in the tissues of those with McCune-Albright syndrome. Despite the identification of the probable molecular mechanism of McCune-Albright syndrome, recognition and treatment of the underlying endocrine disorders remains a continuing challenge to the endocrinologist.

GH, in clinical practice, is determined by RIA, but RIA estimates may not accurately reflect serum GH bioactivity. The available measures of GH bioactivity lack either sensitivity, specificity, or a physiologically relevant end point. The objective of this research was to develop a physiologically relevant GH bioassay which would not only measure the bioactivity of purified GH preparations, but would also have sufficient sensitivity to measure GH bioactivity in human serum. The method consisted of incubating murine 3T3-F442A adipocytes in serum-free medium containing BSA, 14C-glucose, and increasing concentrations of GH or test materials for 24 h, followed by measurement of conversion of glucose to lipid. Interference by nonspecific serum factors was reduced by the addition of 10 micrograms/liter insulin, 25 nM dexamethasone, and 37 nM estradiol to the medium. In the presence of 10 micrograms/liter insulin, 50 micrograms/liter insulin-like growth factor-1 did not alter the ability of GH to suppress lipid accumulation. Epinephrine and glucagon could suppress lipid accumulation but only at concentrations greatly in excess of the physiological range in serum. Twenty two thousand dalton hGH produced dose-dependent suppression of lipid accumulation which was linear between 0.625 and 10 micrograms/liter (r = 0.926; P = 0.0001) with a half-maximal response of 3.0 +/- 0.2 micrograms/liter (n = six experiments). The intra- and interassay coefficients of variation were 7% and 19%, respectively. The assay was specific for GH since addition of human PRL produced suppression of lipid accumulation only at concentrations where contamination of the preparation by GH became a significant factor. ACTH also suppressed lipid accumulation but only at doses of 1000 micrograms/liter or greater. Human placental lactogen and hLH, hFSH, and hTSH did not cross-react with GH in this assay. Addition of human serum did not alter the slope of ED50 of the GH dose-response curve. Pools of serum from prepubertal and pubertal boys and girls, subjects treated with arginine or insulin, a diabetic girl, and a boy with gigantism who had a serum GH content of 80 micrograms/liter by RIA and 40 micrograms/liter by bioassay, produced dose response curves parallel to that of the GH standard curve. Serum from patients with hypopituitarism did not produce significant suppression of lipid accumulation in any assay. Recovery of 5 micrograms/liter GH added to human serum was 94%. Twenty thousand dalton GH also suppressed lipid accumulation in this assay, but was 2-fold less potent than 22,000 dalton GH.(ABSTRACT TRUNCATED AT 400 WORDS)

We tested the hypothesis that the improved sensitivity of immunofluorometric (IFMA) assays will lead to an increase in the number of detectable LH pulses compared to RIA in early pubertal boys, in whom LH secretion is low. To test this hypothesis we determined plasma LH concentrations in six pubertal boys (bone age, 12-16 yr) by IFMA and compared the results to RIA data reported previously. Each boy was given an infusion of saline, followed 1 week later by an infusion of testosterone (T; 960 nmol/h) for 33 h starting at 1000 h. Starting at 1200 h, blood was obtained every 15 min for LH determinations (RIA and IFMA) and every 30 min for T measurements. At the end of both studies, responses to GnRH (250 ng/kg) were assessed. The assay sensitivities for LH by RIA and IFMA (Delfia hLH Spec Pharmacia Diagnostics ENI, Columbia, MA) were 1.0 and 0.05 IU/L, respectively. LH pulses were identified by three independent pulse detection programs: Detect, Cluster, and Kushler-Brown. The correlation for LH values as measured by RIA and IFMA was highly significant (r = 0.81). There was a poor correlation between LH values determined by IFMA and RIA when LH values within 4 times the SD of each assay sensitivity were compared (r = 0.08; P = NS). T infusion suppressed LH pulse frequency by 40% and 66%, as determined by RIA and IFMA, respectively (P = NS). Using the Detect program, during the complete study in all 6 boys, 117 pulses of LH were identified by RIA and 93 by IFMA (79% ratio of detection IFMA/RIA). During saline infusion there were 73 vs. 69 LH pulses (94%), while during T infusion there were 24 vs. 44 LH pulses (55%), as detected by IFMA vs. RIA, respectively. Administration of naloxone did not accelerate LH pulse frequency during T infusion, as determined by either method. Changes in pituitary responses to exogenous GnRH also showed similar trends of augmentation by T infusion by both methods. We conclude that the use of IFMA does not lead to the anticipated increase in the detectability of LH pulsatility. Actually, fewer LH pulses were identified by IFMA in this group of boys. We speculate that this is due to the increased specificity of the IFMA assay. More significant was the finding that the physiological interpretation of the effects of T and naloxone on LH pulse frequency and responses to GnRH did not change whether LH was measured by RIA or IFMA.

Objective To examine whether adolescents’ and parents’ perceptions of patient-centered communication (PCC) with the physician may be associated with aspects of patient empowerment (e.g., perceptions of competence) and diabetes management (i.e., adherence and HbA1c). Methods One hundred and ninety adolescents with type 1 diabetes and their parents rated perceptions of PCC following a clinic visit and completed measures of competence, illness perceptions, self-efficacy, and adherence in the weeks following their clinic visit, and again 6 months later. Metabolic control was indexed from medical records. Results Higher levels of PCC with physicians were associated cross-sectionally and longitudinally with greater perceptions of control and competence for both adolescents and parents. Mediation analyses indicated that PCC was indirectly related to subsequent adherence and metabolic control through perceptions of the adolescent’s competence in diabetes management. Conclusions Perceptions of PCC with healthcare providers may empower adolescents and parents in their diabetes management.

To evaluate the role of endogenous opioid pathways in the acute suppression of LH secretion by testosterone (T) infusion in men, we studied eight normal healthy volunteers who received a saline infusion, followed 1 week later by a T infusion (960 nmol/h) starting at 1000 h and lasting for 33 h. After 2 h of infusion (both saline and T), four iv boluses of saline were given hourly, and after 26 h of infusion, four hourly iv boluses of naloxone were given. Blood was obtained every 15 min for LH and every 30 min for T. T infusion increased the mean plasma T concentration 2.1-fold (18.7 +/- 2.1 to 39.5 +/- 3.5 nmol/L, saline vs. T infusion, P < 0.01). The mean plasma LH concentration was 7.9 +/- 0.5 IU/L during the saline control study and was decreased to 6.9 +/- 0.6 IU/L by the infusion of T (P < 0.05). LH pulse frequency was similar during both saline and T infusions (0.48 +/- 0.02 vs. 0.43 +/- 0.04 pulses/man.h, saline vs. T infusion). The mean LH pulse amplitude decreased from 4.3 +/- 0.4 IU/L during saline infusion to 3.3 +/- 0.2 IU/L during T infusion (P < 0.05). The administration of naloxone increased the mean plasma LH concentration significantly during saline infusion (7.6 +/- 0.4 to 10.0 +/- 0.9 IU/L, saline vs. naloxone boluses, P < 0.01), but not during T infusion (6.9 +/- 0.6 vs. 7.3 +/- 0.6 IU/L). LH pulse frequency increased significantly after the administration of naloxone during both saline and T infusions (0.54 +/- 0.04 to 0.71 +/- 0.08 pulses/man.h, saline vs. naloxone boluses during saline infusion, and 0.46 +/- 0.08 to 0.60 +/- 0.07 pulses/man.h during T infusion; P < 0.05). LH pulse amplitude was suppressed by T infusion, but administration of naloxone did not reverse this suppression. The mean amplitude of the LH response to exogenous GnRH (250 ng/kg) was decreased by T infusion from 48 +/- 13.5 to 31.2 +/- 8.5 IU/L (P < 0.01). Therefore, in men, the administration of naloxone increases LH pulse frequency during both saline and T infusions, but the acute suppression of LH pulse amplitude seen with T infusion was not reversed by naloxone. This pattern contrasts sharply with the effects of T infusion in pubertal boys, as elucidated by our earlier studies. The negative feedback effects of T on LH secretion are primarily hypothalamic in early pubertal boys and change to pituitary suppression in men.

We hypothesized that prepubertal girls with gonadotropin deficiency would produce less follicle-stimulating hormone (FSH) in response to synthetic gonadotropin-releasing hormone (GnRH) than would gonadotropin-sufficient children. To test this hypothesis, we performed 103 GnRH tests serially in 21 children who had idiopathic hypopituitarism with growth hormone deficiency. We tried to predict whether puberty would occur in the 17 girls with bone ages of 8 years or less. Of these 17 girls, 4 failed to have spontaneous secondary sexual characteristics by age 16 1/2 years, and 12 had spontaneous complete pubertal development. One girl had incomplete pubertal maturation with partial gonadotropin deficiency; her results were combined with those of the girls who had no spontaneous pubertal development. With increasing bone age, the girls with complete pubertal development had a decrease in the increment of FSH released in response to GnRH, although basal gonadotropin concentrations did not change. For GnRH tests performed at bone ages of 8 years or less, basal luteinizing hormone (LH) values did not differ between girls with complete puberty and those with absent or incomplete puberty. However, basal FSH and the incremental response of LH and FSH to GnRH were greater in those with complete puberty. Only two girls with prepubertal bone ages at the time of testing, who subsequently had complete puberty, had incremental FSH responses to GnRH that were less than 5 IU/L. Individual incremental LH responses to GnRH did not discriminate well between groups. None of the girls with adrenocorticotropic hormone deficiency, either originally or subsequently, had spontaneous puberty, but 4 of 12 girls with thyrotropin deficiency, either originally or subsequently, had complete puberty. We conclude that a significant increase in GnRH-stimulated FSH suggests that spontaneous pubertal development will occur in girls with idiopathic hypopituitarism. However, a low FSH response to GnRH may not be diagnostic of gonadotropin deficiency.

Little is known about the role of proteins that lack primary sequence homology with any known motifs (proteins with unknown functions, PUFs); these comprise more than 10% of all proteins. This paper offers a generalized experimental strategy for identifying the functions of such proteins, particularly in relation to metabolism. Using this strategy, we have identified a novel regulatory function for Arabidopsis locus At3g30720 (which we term QQS for qua-quine starch). QQS expression, revealed through global mRNA profiling, is up-regulated in an Arabidopsis Atss3 mutant that lacks starch synthase III and has increased leaf starch content. Analysis of public microarray data using MetaOmGraph (metnetdb.org), in combination with transgenic Arabidopsis lines containing QQS promoter-GUS transgenes, indicated that QQS expression responds to a variety of developmental/genetic/environmental perturbations. In addition to the increase in the Atss3 mutant, QQS is up-regulated in the carbohydrate mutants mex1 and sis8. A 586 nt sequence for the QQS mRNA was identified by 5' and 3' RACE experiments. The QQS transcript is predicted to encode a protein of 59 amino acids, whose expression was confirmed by immunological Western blot analysis. The QQS gene is recognizable in sequenced Arabidopsis ecotypes, but is not identifiable in any other sequenced species, including the closely related Brassica napus. Transgenic RNA interference lines in which QQS expression is reduced show excess leaf starch content at the end of the illumination phase of a diurnal cycle. Taken together, the data identify QQS as a potential novel regulator of starch biosynthesis.

OBJECTIVE—This study examined 1) whether the benefits of mothers’ and fathers’ accepting relationships with their adolescents regarding diabetes control were due to parental monitoring and 2) how parents together may provide sufficient acceptance and monitoring for diabetes management. RESEARCH DESIGN AND METHODS—Adolescents aged 10–14 years with type 1 diabetes (n = 185) and their mothers (n = 185) and fathers (n = 145) completed assessments of parental acceptance and monitoring of diabetes tasks. Adolescents completed a modified version of the Self-Care Inventory (1) to measure adherence. A1C scores were used as a marker of glycemic control. RESULTS—Mediational analyses revealed that the benefits of adolescents’ reports of fathers’ acceptance on A1C and mothers’ and fathers’ acceptance on better adherence were partially mediated by monitoring. Both mothers’ and fathers’ monitoring and fathers’ acceptance had independent effects in predicting adherence. However, only fathers’ monitoring had an independent effect on A1C. The effect of fathers’ monitoring on A1C occurred as fathers were monitoring at a lower level than mothers. Mothers’ and fathers’ reports of their own acceptance and monitoring were not associated with A1C or adherence. CONCLUSIONS—Results reveal the importance of fathers’ acceptance and monitoring in diabetes management, a role that should be encouraged, despite the little attention it has received.

Objective: To compare medical, nutritional, and psychosocial outcomes of continuous subcutaneous insulin infusion (CSII) therapy and multiple daily insulin injections (MDI) in preschoolers with type 1 diabetes mellitus (T1DM) in a randomized controlled trial. Study design: Sixteen children (mean age 4.4 ± 0.7 yr, range 3.1–5.3 yr) with T1DM were randomly assigned to CSII or MDI. Hemoglobin A1c (HbA1c) was measured monthly for 6 months. Glucose variability was measured at baseline and at 6 months using continuous blood glucose sensing. Quality of life, adverse events, and nutrition information were assessed. Results: Parents of the CSII group reported a significant decrease in diabetes-related worry, while parents of the MDI group reported an increased frequency of stress associated with their child’s medical care. Mean HbA1c levels from baseline (CSII 8.3 ± 1.4%, MDI 8.0 ± 0.8%) to 6 months (CSII 8.4 ± 0.8%, MDI 8.2 ± 0.4%) remained stable, and group differences were not significant. There were no significant group differences in duration of hypo- or hyperglycemic events or frequency of adverse events. Conclusion(s): For young children with T1DM, CSII therapy is comparable to MDI therapy with regard to glucose control but is associated with higher treatment satisfaction and improved quality of life.

Metabolic networks combine metabolism and regulation. These complex networks are difficult to understand and create due to the diverse types of information that need to be represented. This chapter describes a suite of interlinked tools for developing, displaying, and modeling metabolic networks. The metabolic network interactions database, MetNetDB, contains information on regulatory and metabolic interactions derived from a combination of web databases and input from biologists in their area of expertise. PathBinderA mines the biological “literaturome” by searching for new interactions or supporting evidence for existing interactions in metabolic networks. Sentences from abstracts are ranked in terms of the likelihood that an interaction is described and combined with evidence provided by other sentences. FCModeler, a publicly available software package, enables the biologist to visualize and model metabolic and regulatory network maps. FCModeler aids in the development and evaluation of hypotheses, and provides a modeling framework for assessing the large amounts of data captured by high-throughput gene expression experiments.

BACKGROUND: FSH-regulatory peptides participate with GnRH and sex steroids to regulate serum FSH concentrations. We hypothesized that day/night variations in FSH serum concentrations would be associated with diurnal variation in FSH-regulatory peptides. METHODS: Blood was obtained every 15 min for 24 h beginning at 08:00 h in eight girls [seven with variations in growth or puberty and one with idiopathic hypogonadotrophic hypogonadism (IHH)] and for 12 h beginning at 20:00 h in 12 additional girls with variant puberty, eight with gonadal dysgenesis or ovarian failure (GD/OF) and one with IHH. Samples across 3 h blocks were pooled for determination of LH, FSH, activin-A, inhibin-B and follistatin 288. RESULTS: LH and FSH concentrations increased from 23:00 to 08:00 h with respect to daytime concentrations in pubertal girls (P < 0.005) but only LH increased (P = 0.002) in girls with GD/OF. In pubertal girls, inhibin-B declined during the day (P = 0.019), reaching a nadir between 17:00 and 22:45 h just prior to the night-time increase in FSH. Follistatin concentrations exhibited diurnal variation (P = 0.028), with the greatest concentrations occurring between 05:00 and 11:00 h. Activin-A concentrations declined coincident with the night-time increase in FSH in pubertal girls (P < 0.0001) but not in girls with GD/OF. CONCLUSIONS: The directionality of changes in FSH-regulatory proteins supports the notion that FSH-regulatory peptides may contribute to the night-time augmentation of circulating FSH during puberty in girls.

The increase in pituitary GH secretion that occurs during mid-late puberty in boys follows an increase in circulating testosterone (T) concentration; the direct mechanism by which this occurs is unknown. We hypothesized that T increases GH secretion during puberty by augmenting hypothalamic output of GHRH. Using constant infusions of a GHRH antagonist, we tested this hypothesis in six early pubertal boys with constitutional delay of growth and adolescence who had a mean chronological age of 14.0 +/- 0.3 yr and mean bone age of 11.4 +/- 0.2 yr. Blood samples were obtained from subjects every 15 min for 24 h during the overnight infusion of normal saline (2000-0600 h) and again during the overnight infusion of GHRH antagonist (0.33 microg/kg/h) the following night. Subjects then received transdermal T (5-mg patch) for 12 h nightly and were studied again after 4 wk of treatment. Serum samples were assayed for GH and total ghrelin; the percent suppression of GH during GHRH antagonist infusion was calculated. Morning serum T rose from 0.44 +/- 0.09 to 4.43 +/- 0.74 microg/liter (P = 0.005). T treatment was associated with a 92.6% increase in mean nocturnal GH secretion area under the curve (830 +/- 177 to 1599 +/- 340 microg/24 h.liter). Infusion of GHRH-antagonist suppressed mean nocturnal GH area under the curve by 29.1% before T treatment (830 +/- 177 to 621 +/- 168 microg/24 h.liter), and by 29.4% after T treatment (1599 +/- 340 to 1182 +/- 249 microg/24 h.liter; P = 0.99). Somatotroph sensitivity to GHRH was tested with 0.1- and 1.0-microg/kg doses of GHRH-44 iv; GH response did not change with regard to T treatment. The mean 24-h concentration of total ghrelin was unchanged with regard to T treatment. In summary, nightly transdermal T administration in six boys with constitutional delay of growth and adolescence increased GH output almost 2-fold, whereas the degree of GH suppressibility by GHRH antagonist remained unchanged. We conclude that the T-associated augmentation of GH secretion during early puberty in boys is unlikely to involve an absolute increase in hypothalamic GHRH output.

BACKGROUND: FSH concentrations are higher in girls than in boys before puberty. We hypothesized that steroid-mediated changes in FSH-regulatory proteins underlie the sex differences in FSH secretion and pubertal timing. METHODS: FSH-regulatory proteins, LH, FSH and sex steroids were measured in five boys, 10 girls, and five girls with Turner syndrome before and during sex steroid treatment (girls, 0.05 mg/day estradiol; boys, 5 mg/day testosterone) for up to 4 weeks. Blood was obtained every 15 min from 20.00 to 08.00 h before and during sex steroid treatment. RESULTS: The mean FSH concentration was higher in girls than in boys (P = 0.0044). Activin-A concentrations were greater (P < 0.0001) and inhibin-B concentrations lower (P < 0.0001) in girls compared with boys. Steroid treatment (i) suppressed LH/FSH concentrations in all subjects; (ii) increased the mean activin-A concentration in all but the Turner girls (P = 0.001); and (iii) decreased inhibin-B concentrations in boys (P = 0.005) but not in girls. Total follistatin and follistatin 288 concentrations did not differ by sex. CONCLUSIONS: Sex steroids regulate circulating activin-A and inhibin-B concentrations in children. The lower inhibin-B and higher activin-A concentrations may explain the higher FSH and earlier onset of puberty in girls.

MetNet (http://www.botany.iastate.edu/∼mash/metnetex/metabolicnetex.html) is publicly available software in development for analysis of genome-wide RNA, protein and metabolite profiling data. The software is designed to enable the biologist to visualize, statistically analyse and model a metabolic and regulatory network map ofArabidopsis, combined with gene expression profiling data. It contains a JAVA interface to an interactions database (MetNetDB) containing information on regulatory and metabolic interactions derived from a combination of web databases (TAIR, KEGG, BRENDA) and input from biologists in their area of expertise. FCModeler captures input from MetNetDB in a graphical form. Sub-networks can be identified and interpreted using simple fuzzy cognitive maps. FCModeler is intended to develop and evaluate hypotheses, and provide a modelling framework for assessing the large amounts of data captured by high-throughput gene expression experiments. FCModeler and MetNetDB are currently being extended to three-dimensional virtual reality display. The MetNet map, together with gene expression data, can be viewed using multivariate graphics tools in GGobi linked with the data analytic tools in R. Users can highlight different parts of the metabolic network and see the relevant expression data highlighted in other data plots. Multi-dimensional expression data can be rotated through different dimensions. Statistical analysis can be computed alongside the visual. MetNet is designed to provide a framework for the formulation of testable hypotheses regarding the function of specific genes, and in the long term provide the basis for identification of metabolic and regulatory networks that control plant composition and development.

Objective. To determine social factors associated with increased risk of hospital admission from diabetic ketoacidosis (DKA) or diabetic coma as well as risk of prolonged hospital stay.Methods. A cohort of all children (≤21 years) with type 1 diabetes mellitus (DM) in the National Inpatient Sample admitted for DKA or diabetic coma during 1996 or 1997 was conducted. Patients’ age, race, gender, and insurance coverage were identified. Length of stay and charges were examined; prolonged length of stay was defined as ≥7 days.Results. A total of 8443 children with a primary hospital diagnosis of DKA and 123 children with type 1 DM and coma were identified; 55% of the children were girls, 32% were nonwhite, 29% received Medicaid insurance, and 33% resided in areas of poverty. Children with prolonged hospital stay were significantly more likely to be of nonwhite race (odds ratio [OR]: 2.0; 95% confidence interval [CI]: 1.6–2.5), to receive Medicaid insurance (OR: 1.4; 95% CI: 1.1–1.7), to live in areas of poverty (OR: 1.3; 95% CI: 1.1–1.7), and to be of younger age.Conclusions. When compared with state census data, nonwhite and poor children were more likely to be admitted with complications of DM and to have significantly prolonged and expensive hospital stays. These children should be targeted for intensive diabetes education and outpatient medical support both to improve their health and potentially to decrease total health care costs.

Japanese pagodatree (Styphnolobium japonicum [L.] Schott) and American yellowwood (Cladrastis kentukeaDum.-Cours.) Rudd are the first woody, non-nodulating papilionoid legumes shown to possess putative early nodulin 2 (ENOD2) genes. ENOD2 cDNAs from Japanese pagodatree (807 bp) and American yellowwood (735 bp) have 75% to 79% sequence identity to ENOD2 sequences and encode deduced proteins that possess conserved ENOD2 pentapeptides (PPHEK and PPEYQ). Lower percentages of glucose and higher percentages of histidine and valine suggest that SjENOD2 andCkENOD2 are different from other ENOD2s. Hybridization analyses indicate the clones representENOD2 gene families of two to four genes in Japanese pagodatree and American yellowwood genomes, andENOD2-like transcripts were detected in stems and flowers, as well as roots. Only roots of control species that nodulate,Maackia amurensis Rupr. & Maxim. and alfalfa (Medicago sativa), produced pseudonodules after treatment with zeatin or 2,3,5-triiodobenzoic acid, an auxin transport inhibitor. Accumulation of MaENOD2 transcripts was enhanced during the first 10 d of treatment, but 2,3,5-triiodobenzoic acid and zeatin enhanced transcript accumulation after 30 d in roots of Japanese pagodatree and American yellowwood. Characteristics that distinguish ENOD2 gene families in basal, non-nodulating woody legumes from otherENOD2 genes may provide new information about the function of these genes during symbiotic and non-symbiotic organ development.

Serum concentrations of inhibin A, inhibin B, activin A and follistatin were determined using two-site enzyme-linked immunosorbent assays (ELISA) during pubertal ovarian development in 28 girls and five follicular phase women. Blood obtained every 15 to 20 min overnight was pooled for peptide determination. Serum inhibin A concentrations increased in mid puberty, exhibiting positive correlations with bone age (r = 0.527, P = 0.0016) and oestradiol concentrations (r = 0.581, P = 0.0005). Inhibin B concentrations peaked in mid puberty and declined thereafter, but remained greater than concentrations seen in prepubertal girls, and correlating positively with oestradiol (r = 0.362, P = 0.046) and follicle stimulating hormone (FSH) concentrations (r = 0.369, P = 0.038). Total activin A concentrations did not vary significantly across pubertal stages. Total follistatin concentrations, determined by radioimmunoassay, decreased with advancing puberty, exhibiting negative correlations with bone age (r = -0.634, P = 0.0001) and oestradiol concentration (r = -0.687, P = 0.0001). Follistatin concentrations determined by an ELISA specific for follistatin 288 were greatest in mid-pubertal girls, but concentrations in late puberty were less than those in early puberty. The free follistatin assay indicated that all circulating follistatin was activin-bound. These results suggest that significant changes in serum concentrations of FSH-regulatory peptides accompany the onset of puberty.

Puberty in boys is characterized by a nocturnal increase in mean LH concentration and LH pulse frequency. To determine whether similar mechanisms exist in girls, nocturnal serum LH concentrations were determined in 16 girls with constitutional delay of adolescence or idiopathic short stature who had or have subsequently been shown to have spontaneous puberty. Mean LH and LH pulse frequency and amplitude were analyzed in 3-h blocks and compared to those in 20 pubertal boys. Girls had an increase in mean LH concentration from 3.6 +/- 0.7 IU/L at 2000-2250 h to 4.8 +/- 0.9 IU/L at 0200-0450 h. LH pulse frequency increased from 0.27 +/- 0.11 pulses/girl.h at 2000-2250 h to 0.54 +/- 0.10 pulses/girl.h at 0200-0450 h. The increase in LH pulse amplitude, from 2.0 +/- 0.8 IU/L at 2000-2250 h to 4.1 +/- 1.1 IU/L at 2300-0150 h, did not achieve statistical significance because many girls had no pulses from 2000-2250 h. With advancing age, the day/night differences in LH concentration and LH pulse frequency disappeared in girls, but were preserved in boys of same pubertal stage. The effect of lack of estrogen on LH pulse characteristics was inferred by analyzing the LH profiles of 15 girls with gonadal dysgenesis who were age-matched to girls with spontaneous puberty. The girls with gonadal dysgenesis had an increase in mean LH concentration after 0200 h, but LH pulse frequency was rapid in all time blocks; the nocturnal increase in LH concentration was secondary to a significant increase in LH pulse amplitude. Older girls with gonadal dysgenesis had a loss of nighttime augmentation of LH secretion similar to that seen in girls with spontaneous puberty. These data suggest that the apparent slower LH pulse frequency encountered in girls with spontaneous puberty during waking hours may be related to estrogen suppression of LH pulse amplitude, which masks the true daytime LH pulse frequency. With or without pubertal estrogen exposure, developmental progression of LH secretion occurs more rapidly in girls than in boys. Thus, intrinsic sex differences exist in the timing and tempo of endocrine control of pubertal maturation between boys and girls.

Growth hormone (GH) appears to affect the timing of puberty in children. The effects of GH on puberty may be related to direct GH action on ovarian function or may be mediated by IGF-I. To determine the likelihood that GH has direct effects on ovarian function, we compared the ability of GH and IGF-I to increase luteinized granulosa cell steroidogenesis in the absence and presence of gonadotropins. Cells were obtained from women undergoing in vitro fertilization for tubal disorders or male factor infertility and were placed in static culture. GH alone failed to alter progesterone or estradiol accumulation in the medium of cultured luteinized granulosa cells. IGF-I produced no increase in progesterone accumulation but increased estradiol accumulation 5.6-fold compared with cells treated with vehicle. The combination of GH and FSH produced an 0.83-fold increase in estradiol accumulation, whereas the combination of IGF-I and FSH resulted in a 2.9-fold increase in estradiol accumulation above FSH alone. Thus the direct effects of GH on granulosa cell steroid synthesis are modest compared with those of IGF-I. If GH has an effect on ovarian development at puberty, it is likely to be mediated by a GH-induced increase in circulating IGF-I.

LH secretion is maximal during the night in pubertal boys, and testosterone (T) administration blunts this nocturnal rise of LH. We have previously shown that in pubertal boys, the acute negative feedback effects of T infusion on LH secretion during the daytime cannot be reversed by opioid receptor blockade. To determine whether the nocturnal secretion of LH in early puberty is regulated by endogenous opioid pathways, we determined whether naloxone during the night affected LH secretion or T-mediated suppression of LH secretion. Seven pubertal boys (bone age, 11-13.5 yr) were given a control infusion of saline, followed 1 week later by an infusion of T at 960 nmol/m2.h for 41 h starting at 2000 h. During both saline and T infusions, six iv boluses of saline were given hourly beginning at 2400 h on the first day, and six iv boluses of naloxone (0.1 mg/kg each) were given hourly beginning at 2400 h on the second day. Starting at 2200 h, blood was obtained every 15 min for LH and every 30 min for T determinations for 14 h each night. Pituitary responsiveness was assessed at the end of each study night by i.v. bolus administration of 250 ng/kg synthetic GnRH. T infusion increased the mean T concentration 6-fold (P0.0001) and suppressed the mean plasma LH concentrations from 5.6 +/- 0.6 to 3.8 +/- 0.6 IU/L (P0.01). The nocturnal augmentation of LH secretion was suppressed by the infusion of T, and this suppression was not reversed by naloxone. The mean nighttime plasma LH (2400-0600 h) was 8.1 +/- 1.1 IU/L during the control saline infusion and 5.1 +/- 0.6 IU/L during the T infusion (P0.01). The mean LH level was 4.0 +/- 0.7 IU/L during the administration of naloxone boluses concomitantly with the T infusion, not significantly different from that during the T infusion. Likewise, LH pulse frequency during the same time period was decreased by T infusion from 0.6 +/- 0.1 to 0.36 +/- 0.04 pulses/boy.h (P0.05), and it was unaltered by coadministration of naloxone (0.38 +/- 0.12 pulses/boy.h). Naloxone administration during the saline infusion did not increase either the mean plasma LH concentration (7.5 +/- 0.7 IU/L; P = NS vs. saline control) or the LH pulse frequency (0.69 +/- 0.1 pulses/boy.h; P = NS vs. saline control). Pituitary responsiveness to GnRH was similar on each of the 4 nights during either saline or T infusions.(ABSTRACT TRUNCATED AT 400 WORDS)

In this study we wished to test whether, and if so when, the suppressive effects of testosterone on LH and, by inference, GnRH secretion are mediated via endogenous opioid pathways during male pubertal maturation. As a preliminary study, we evaluated the acute effects of a 24-h infusion of testosterone (T) in eight pubertal boys with constitutional delay of growth in order to determine the optimal time for administration of naloxone. Eight additional pubertal boys received a saline infusion, followed 1 week later by a similar T infusion starting at 1000 h and lasting for 33 h. After 2 h of infusion (both saline and T), four iv boluses of saline were given hourly, and after 26 h of infusion, four hourly iv boluses of naloxone were given. Blood was obtained every 15 min for LH and every 30 min for T measurements. T infusion increased the mean T concentration by 3.8-fold (P less than 0.001). Mean LH and LH pulse frequency were suppressed (P less than 0.01), and the sleep-associated increase in LH secretion was abolished. Naloxone administration during the infusion of T did not reverse the suppression of LH secretion. Compared to the saline control period, mean LH was significantly lower during T infusion during the time naloxone boluses were given (4.5 +/- 0.9 vs. 5.9 +/- 1.1 IU/L, T infusion and naloxone boluses vs. saline respectively, P less than 0.01). Although the suppression of LH pulse frequency remained significantly lower than that during the saline control period (0.23 +/- 0.04 pulses/boy.h during T infusion and saline boluses; 0.33 +/- 0.04 pulses/boy.h during T infusion plus naloxone boluses; 0.44 +/- 0.06 pulses/boy.h during saline infusion and saline boluses). Naloxone increased mean LH and LH pulse frequency only in the four older, more mature boys during the infusion of saline. Pituitary responsiveness to exogenous GnRH was not altered by infusion of T. We conclude that acute administration of T suppresses LH secretion and, by inference, GnRH secretion at all stages of pubertal maturation in boys. These negative feedback effects, however, cannot be reversed by coadministration of naloxone, even in mid- to late pubertal boys who respond to naloxone with increased pulsatile secretion of LH. These studies suggest that during pubertal maturation in boys, endogenous opioid pathways do not play a major role in the regulation of the negative feedback effects of T.

The microheterogeneity and bioassayable activity of serum FSH (B-FSH) can be regulated by exogenous GnRH in boys with idiopathic hypogonadotropic hypogonadism and by estrogen in a women with gonadal dysgenesis, presumably via hormonally mediated changes in the degree of FSH glycosylation. To test the hypothesis that testosterone (T) regulates the circulating forms of B-FSH, we raised the serum T levels of early pubertal boys to adult levels. In this model, high dose T inhibits the pubertal nocturnal augmentation of LH secretion, apparently through decreased GnRH secretion. This model allowed us to test a second hypothesis, that B-FSH is a sensitive indicator of hypothalamic GnRH release. The boys were studied on two consecutive weekends, during which they received either saline (S) or T infusions. Beginning at noon on the study day, after an overnight acclimatization, the boys received either S or T at 33% or 100% of the adult male production rate. Blood was sampled from 2000-0800 at 10-min intervals for immunoactive LH and FSH (I-FSH) and for B-FSH, as determined by the in vitro Sertoli cell aromatase induction assay, and at 30-min intervals for T. Gonadotropin levels were analyzed as mean hourly or 3-h concentrations and as pulse profiles by two established objective peak detection programs, Cluster and Detect. During S treatment, mean LH increased after the onset of sleep (P = 0.0006) and, after plateauing for several hours, declined to baseline in the early morning hours. Mean levels of B-FSH were also minimally (but significantly) increased after the onset of sleep (P = 0.046) and paralleled the decline noted for LH. Mean levels of I-FSH did not demonstrate a diurnal rhythm. The effect of T was gonadotropin specific. High dose T abolished the nocturnal elevation in mean LH concentrations, but had no effect on the nocturnal elevation of B-FSH (P less than 0.05) or on I-FSH levels. The LH pulse frequency was greatest from 2300-0450 h, during S treatment (P = 0.016). The pulse frequency of B-FSH was also minimally increased after the onset of sleep (P = 0.045). The T infusion abolished the nocturnal increase in LH pulse frequency, without an effect on B-FSH pulse frequency. B-FSH pulse frequency exceeded LH pulse frequency during S treatment (8.0 +/- 0.7 pulses/12 h vs. 5.5 +/- 0.4), and B-FSH pulses persisted throughout the night. The pulse amplitudes of LH and B-FSH were not affected by T.(ABSTRACT TRUNCATED AT 400 WORDS)

Ghrelin is a peptide produced principally in the stomach that increases appetite and participates in stimulation of growth hormone (GH) secretion. Obese children have low GH concentrations that increase after fasting. We hypothesized that an increase in ghrelin concentrations with fasting might participate in the subsequent increase in GH secretion. Subjects included 5 lean girls ages 9 to 14 years in stage I to III puberty who had body mass index standard deviation scores (BMI SDS) of -1.8 to -0.5 and delayed adolescence and/or short stature. Nine obese girls ages 6 to 11 with BMI SDS of 4.0 to 10.6 in stage I to III puberty were also studied. The lean girls and 7 of the obese girls were studied in the ad libitum fed state. Seven obese girls, including 5 studied in the fed state, were studied in the final 24 h of a 48 h fast consisting of 25% of calories estimated to be appropriate for ideal body weight. Blood was obtained every 15 min for 24 h beginning at 0800h and assayed for GH. Total ghrelin was determined in 8 samples consisting of an equal aliquot of each 15-min sample in a 3-hour period beginning at 0800h for 24 h. Lean girls had significantly greater ghrelin concentrations than did fed obese girls (0.41 ± 0.03 vs 1.6 ± 0.01 ng/mL, p

Desiccation damage in ornamental plant species is of particular concern to the nursery and landscape industry. Species in two genera, Acer and Alnus, display fundamental differences in how drought affects leaves. The same soil moisture content that causes foliar desiccation and abscission in Alnus maritima (Marsh.) Nutt. (seaside alder) causes neither response in Acer rubrum L. (red maple). Understanding molecular mechanisms associated with plant response to drought stress can be an im portant factor in developing strategies for improved sustainability in urban landscapes. Our objective was to characterize expression of drought-induced dehydrin genes in leaves of `Red Sunset' red maple (desiccation-resistant) and seaside alder (desiccation-sensitive) in response to dehydration and rehydration. Potted cuttings grown in a glasshouse were subjected to four cycles of drought and rehydration. Stomatal conductance and volumetric moisture content of rooting medium were used to determine when drought cycles ended. During the second and fourth cycles, leaves were sampled for RNA and protein extraction. Dehydrin probes were generated from genomic DNA of both species by using PCR with primers designed from conserved regions in dehydrin genes. Southern blot analyses revealed the presence of dehydrin genes in seaside alder and red maple genomes. Reverse transcriptase (RT)-PCR was used to isolate desiccation-induced dehydrin cDNAs from total RNA extracted from drought-stressed leaves. The cDNA clones show 61% to 66% identity at the nucleic acid level with dehydrin genes of soybean, sunflower, radish, and potato. Accumulation of dehydrin transcripts and proteins in leaves in response to dehydration and rehydration are being studied through northern and western blot analyses, respectively. Our results may lead to a rapid screening technique for seedlings with improved mechanisms of drought resistance.

Early nodulin genes, such as ENOD2, play a role in the first stages of nodulation. Although ENOD2 is conserved among nodulating legumes studied to date, its occurrence and activity have not been studied among woody legumes such as Maackia amurensis Rupr. & Maxim. Our objective was to localize MaENOD2 transcripts during nodule development and describe the anatomy of nodules formed on the roots of M. amurensis in relation to ENOD2 mRNA accumulation. Nodules (2 mm in diameter, and mature) were prepared for light microscopy, sectioned, and stained with safranin and fast green for structural contrast or with the periodic acid Schiff's reaction for starch. The location of ENOD2 transcripts was determined by using in situ hybridization with DIG-labeled sense and antisense RNAs transcribed from a 602-bp fragment of the coding region of MaENOD2. Mature nodules from M. amurensis possessed peripheral tissues, a distal meristem, and a central infected region characteristic of indeterminant development. In situ hybridization showed that MaENOD2 transcripts accumulated in the distribution layer and uninfected cells of the central symbiotic region. Amyloplasts that contained starch grains were identified in these tissues and in the inner parenchyma of the nodule. Throughout nodule development, transcripts were restricted to areas with high levels of stored starch that surrounded cells actively fixing N2. Our results suggest that ENOD2 in M. amurensis may be a cell wall component of tissues that regulate nutrient flow to and from sinks, such as symbiotic regions of a nodule. These data may lead to a better understanding of the role of the ENOD2 gene family during nodulation.

Risk for Early Onset of Depression: Severe Stress and Neuroendocrine Regulation in Children