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Pediatric obesity is a growing and alarming global health problem and represents an important determinant of morbidity. Since nutrition plays an important role in regulating growth and development, the excess weight gain related to overnutrition can affect growth patterns, bone maturation and pubertal development. The purpose of this review was to summarize the current knowledge about the effect of primary obesity on linear growth and pubertal development in children and adolescents. Evidence about regulatory hormones and adipokines that may be involved in the physiology of childhood growth in the context of obesity were also discussed. The most recent literature confirms previous studies indicating that linear growth is accelerated (mainly due to longer trunks rather than longer legs) and bone age is advanced in prepubertal children with obesity, while there is a reduction of pubertal height gain and attainment of normal adult height. Conflicting results are reported on the timing of puberty, specifically in boys. Indeed, previous studies suggested earlier onset of puberty in obese girls and overweight boys, and a delayed puberty in obese boys. Conversely, the most recent studies show more consistently an earlier onset and completion of pubertal development also in boys with obesity. Considering the false belief of health associated with transient taller stature in children and the adverse outcomes related to early puberty, interventions on diet and physical activity are urgently needed to tackle the epidemics of childhood obesity in public health and clinical setting.

Background: non-autoimmune thyroid disorder is a common finding in celiac patients, more frequent than in the general population. An impairment of iodine absorption has been hypothesized, but it has never been investigated so far. We aimed to evaluate the iodine absorption in children and adolescents with newly diagnosed celiac disease. Methods: 36 consecutive celiac patients (age 7.4 years, range 2.4-14.5 years) before starting a gluten-free diet (GFD) were enrolled. We assayed the urinary iodine concentration (UIC) in a 24-h urine sample, at baseline (T0) after 3 (T1) and 12 months (T2) of GFD. Results: UIC at T0 was 64 μg/L (IQR 45-93.25 μg/L) with an iodine deficiency rate of 77.8%. UIC was not different according to histological damage, clinical presentation (typical vs atypical); we found no correlation with the thyroid function tests and auxological parameters. UIC was not statistically different at T1 (76 μg/L) and T2 (89 μg/L) vs T0. UIC at T2 was similar between patients with positive and negative anti-transglutaminase antibodies at T2. No patients presented overt hypothyroidism during the study. Conclusions : We found that iodine absorption in celiac children is impaired compared to the general population; it increases slightly, but not significantly, during the GFD. We should regularly reinforce the need for a proper iodine intake in celiac disease patients to reduce iodine deficiency risk.

Aim: No data are available on caffeine consumption among Italian adolescents. We investigated caffeine intake from coffee, soft drinks and energy drinks in a sample of Italian adolescents and determined if they exceeded the recommended limits., Methods: The study comprised 1213 adolescents with a mean age of 15.1 years (range 12-19) from four schools in Foggia, southern Italy. Caffeine intake was assessed using an anonymous self-reported questionnaire during the 2013/2014 school year. We calculated the percentage of daily caffeine consumers, their mean intake of caffeine from beverages and the contribution of each beverage category to the total caffeine intake., Results: Approximately 76% of the sample consumed caffeine every day, amounting to 125.5 ± 69.2 mg/day and 2.1 ± 1.2 mg/kg/day. When we applied the reference values from the Academy of Pediatrics, we found that 46% of the adolescents exceeded the recommended upper limits. Coffee was the most frequently consumed caffeinated drink and the main contributor to daily caffeine intake., Conclusion: More than three quarters (76%) of the Italian adolescents in our study drank coffee on a daily basis and nearly half (46%) exceeded the recommended upper limits. Strategies are needed to reduce caffeine consumption by adolescents., (©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

The aim of the replacement therapy with levothyroxine in congenital hypothyroidism (CH) is to correct hypothyroidism and ensure normal growth and neuropsychological development. Few data are available about the appropriate dose during childhood and early adolescence; therefore, we performed a multicenter observational study in a large population of patients with CH to assess the required levothyroxine dose to obtain euthyroidism. We recruited 216 patients with permanent CH classified into three groups (agenesia, ectopia, and in situ gland) on the basis of the thyroid imaging. The levothyroxine dose was recorded at 6 and 12 months and then yearly until 12 years of age. The daily levothyroxine requirement progressively decreased during the follow-up, irrespective of etiology. It was significantly lower in patients with in situ gland than in patients with athyreosis during the entire study period and with ectopic gland from the age of 1 year. The levothyroxine requirement at 6 months of age was correlated with the requirement at each later time-point. The daily dose was modified less frequently in patients with in situ thyroid (36 %) than in patients with ectopic gland (41.4 %) or with athyreosis (43.6 %). Patients with in situ gland required a lower dose than the other two subgroups. The dose at 6 months seems predictive of the requirement until 12 years of age. Euthyroidism may be achieved in pre-school and in-school patients by 3-4 and 2-3 µg/kg/day (70-90 and 60-80 µg/m(2)/day) of levothyroxine, respectively.

Background: Linear growth and final height are reported as normal in congenital hypothyroid patients in the neonatal screening era., Methods: We evaluated the final height in 215 patients with congenital hypothyroidism to assess if it improved over the last 2 decades., Results: Final height (-0.1 ± 1.0 SDS) was higher than target height (-0.8 ± 1.0 SDS, p < 0.001) and not different among the 4 quartiles for birthdate. It was correlated with target height (r(2) = 0.564, p < 0.001) and height at puberty onset (r(2) = 0.685, p < 0.001), but not with age at diagnosis or the starting LT4/kg/day dose. The curve fitting analysis showed that the age at diagnosis progressively decreased during the 20-year study period, while the target height and the starting LT4/kg/day increased. Final height was not affected by the birthdate, the age at diagnosis, the starting LT4 dose., Conclusions: The final height is higher than the target height, but despite the improvement in the screening and the treatment, it did not improve over the last 20 years. These findings are in keeping with the described secular trend and suggest that earlier diagnosis and replacement therapy do not significantly modify final height in these patients.

Objective: Mitotane is an adrenocytolytic agent used in adrenocortical carcinoma, inducing adrenal insufficiency, requiring replacement treatment. Such therapy is not easy to monitor because of mitotane interference. Salivary cortisol reflects a free fraction of plasma cortisol and may be useful in such patients., Design: The aim of our study was to evaluate salivary cortisol by HPLC coupled to tandem-mass spectrometry (LC-MS/MS) and by an electrochemiluminescence immunoassay (ECLIA) in patients treated with mitotane. We enrolled 6 patients receiving mitotane and 2 Addison disease patients as negative controls and determined salivary cortisol rhythm. We also determined the salivary cortisol rhythm in 8 healthy subjects. Salivary samples (n=112) were assayed by ECLIA, using Roche Modular E170, and by LC-MS/MS., Results: The mean values obtained by ECLIA were significantly higher than those obtained by LC-MS/MS in the mitotane group (p<0.001). In fact, in the group measured by LC-MS/MS, we observed several peaks eluting at a retention time different from the cortisol group, presumably due to cortisol-like analogues. In Addison disease, since steroidogenesis is absent, salivary cortisol values measured by the two methods did not show any significant difference (p=0.61)., Conclusions: Salivary cortisol measured by LC-MS/MS is a selective method, excluding cortisol analogues accumulating in treated patients. Therefore, LC-MS/MS offers an effective system to monitor replacement therapy in mitotane treated patients.

Background: The poor comparability of growth hormone (GH) results obtained using commercially available methods, is partly due to standard preparations used in calibration. The system relies on the use of the International Reference Preparation (IRP) international standard (IS) 80/505, of human pituitary origin, containing all GH isoforms. Recently, a 22K recombinant GH isoform IRP IS 98/574 was commercialized. Our aim was to evaluate the influence of both calibrators on GH results., Methods: GH concentration in 97 serum samples from children undergoing a growth hormone releasing hormone+arginine stimulation test was measured using Siemens IMMULITE electro-chemiluminescence method, calibrated with both IS 80/505 and IS 98/574 (GRH Growth hormone-Recombinant 98/574-kit)., Results: Comparison of our results obtained with the two sets of calibrators showed good correlation, although we found higher percentage variation (var%) than that stated by Siemens. The mean var% value was confirmed when all results were sub-divided into subgroups based on both high and low GH concentrations., Conclusions: Since the GH assay is influenced by a variety of binding proteins, isoforms and conversion factors, standardization of the assay is strongly required. In Italy, the Agenzia Italiana del Farmaco 39 note provides GH laboratory values which are useful for therapy. On the basis of our results, we therefore propose to adjourn these GH values in order to ensure better management of patients with GH-related disorders.

Background: Retinol-binding protein 4 (RBP4) is an adipocyte-derived 'signal' that may contribute to the pathogenesis of insulin resistance and Type 2 diabetes. The relationship of RBP4 with insulin resistance and metabolic risk in human beings has been the subject of several studies. Subjects born small for gestational age (SGA) are at risk of insulin resistance and Type 2 diabetes. Though RBP4 could represent an early marker of insulin resistance, to date, none have determined RBP4 in SGA children., Aim: Our aim was to measure RBP4 concentrations in cord blood of SGA newborns compared with those in children born with a birth weight appropriate for gestational age (AGA) and to determine whether serum RBP4 levels at birth correlate with insulin sensitivity markers., Subjects and Methods: Sixty-four newborns, 17 born SGA (mean gestational age: 36.4+/-2.1 weeks), and 47 born AGA (mean gestational age: 37.0+/-3.6 weeks) were studied. The main outcome measures included anthropometry, lipid profile, insulin, homeostasis model assessment, quantitative insulin-sensitivity check index, adiponectin, and RBP4., Results: RBP4 concentrations were significantly reduced in SGA newborns (p<0.002). No relationship was found between RBP4 and insulin sensitivity parameters. Stepwise regression analysis revealed that birth weight was the major predictor of RBP4 serum concentrations (p<0.001)., Conclusion: RBP4 is reduced in SGA newborns, birth weight representing the major determinant of RBP4 concentrations, and is not related to insulin sensitivity. No significant difference in adiponectin levels and insulin sensitivity markers was found between SGA and AGA neonates.

Ag-specific cellular immune responses result in CD4+ T cell activation, which can induce the expression of tissue factor in cells of monocyte/macrophage lineage. This results in initiation of the coagulation protease cascade, with ultimate generation of thrombin. The latter is a potent and pleiotropic mediator of cellular responses and deposition of fibrin. To explore the requirements for extravascular cellular mediation of immune effector pathways, we have searched for a cellular source of the cofactor factor Va. Factor V mRNA was identified in human lymphoid cells by using reverse transcription followed by the polymerase chain reaction (RT-PCR). We confirmed our reverse transcription-polymerase chain reaction results by an independent cloning of factor V cDNA from a T cell cDNA library. The sequence of the factor V cDNA was virtually identical to hepatic factor V mRNA sequence. A limited span of mRNA, encoding part of the connecting region of the factor V protein, was found to contain nucleotide polymorphisms based on six nucleotide substitutions. Northern blot analysis confirmed the presence of a approximately 7-kb factor V mRNA in the Hut-78* human T lymphoma cell line and, at five- to eightfold less abundance, in unstimulated lymphocytes and long term allogeneic stimulated T cells. Immunocytology with factor V mAb identified factor V intracellularly in freshly isolated T lymphocytes but not on the surface of cells. These data provide evidence for factor V transcription and biosynthesis by human lymphocytes. They provide an additional perspective on how lymphocytes may contribute to inflammatory effector functions of cellular immune responses in extravascular sites through provision of cofactors necessary for the coagulation serine protease cascade.

Human antibody Fab fragments that bind to hepatitis B surface antigen (HBsAg) were generated by using a recombinant phage surface-display expression system. Characterization of HBsAg-specific Fab fragments isolated from two vaccinated individuals reveals diversity in specificity of antigen binding and in the sequences of the complementarity-determining region. The sequence results show examples of human light-chain promiscuity that result in fine specificity changes and a strong relationship to a human germ-line gene. This application illustrates further that this technique is a powerful tool to isolate distinct human antibodies against immunogenic viral targets.

Streptococcal antigen I/II or the surface protein antigen A (SpaA) of Streptococcus sobrinus is an adhesin which mediates binding of the organism to tooth surfaces. The complete sequence of the gene which encodes SpaA has been determined. The gene consists of 4,584 bp and encodes a protein of 1,528 amino acid residues. The deduced amino acid sequence shows extensive homology with those of the cell surface adhesins from Streptococcus mutans serotypes c and f and from Streptococcus sanguis. Structural analysis of the N-terminal region (residues 50 to 550), which is rich in alanine and includes four tandem repeats of an 82-residue sequence, suggests that it adopts an alpha-helical coiled-coil conformation. Cell surface hydrophobicity may be associated with this region. The C-terminal region is more conserved and includes two tandem repeats of a 39-residue proline-rich sequence. A further proline-rich sequence in this region is predicted to span the cell wall. Although a hydrophobic sequence is present in the C-terminal region, it appears to be too short to span the cell membrane. Anchoring of SpaA in the cell membrane may therefore require some form of posttranslational modification or association with another membrane protein.

A portion of the antigen I/II (spaA, B, P1) gene of Streptococcus sobrinus 6715, containing the coding sequence for the amino terminal 684 amino acids of the protein, was cloned in bacteriophage lambda GT10. Selection was by immunological detection using a polyclonal antiserum to the antigen I/II from Strep. mutans. From the amino acid sequence, peptides were synthesized, 15 amino acids in length, that covered the entire sequence. In total, 260 synthetic peptides were synthesized and evaluated for their immunogenicity in Balb/C mice. Thirty-nine peptides were immunogenic, without carrier, and the antisera generated were tested for their ability to bind cells of Strep. mutans and Strep. sobrinus in a solid-phase assay. Antisera corresponding to peptides from five regions on the I/II molecule bound cells of both bacterial species. These peptides were then evaluated for their ability to stimulate in vitro murine lymphocyte proliferation, after in vivo immunization with Strep. sobrinus cells. Two of the peptides were capable of stimulating proliferation, as determined by incorporation of [3H]-thymidine into murine lymph node cells. The sequences of these 5 peptides were then compared to sequences found in the antigen I/II from Strep. mutans (Kelly et al., 1989). As expected, there was considerable homology between the cross-reactive peptides synthesized and the analogous region from Strep. mutans. This homology was not usually contiguous and suggests that the antibodies bind a face of antigen I/II that is in an alpha-helical conformation.(ABSTRACT TRUNCATED AT 250 WORDS)

[C93] is a novel, extranuclear mutant of Neurospora crassa which has a normal mitochondrial phenotype when grown at 25 degrees, but which is deficient in cytochromes b and aa3 when grown at 37 degrees (Pittenger and West 1979). In the present work, the phenotype of [C93] was characterized in greater detail. When [C93] is grown at 37 degrees, the rate of mitochondrial protein synthesis is decreased to approximately 25% that of wild type; the ratio of mitochondrial small to large ribosomal subunits is decreased to 1:4 and mitochondrial small subunits are deficient in the mitochondrially-synthesized protein, S-5. The mitochondrial ribosome assembly defects in 37 degrees-grown [C93] resemble those in chloramphenicol-treated wild-type cells and could merely be a consequence of the decreased rate of mitochondrial protein synthesis. Analysis of mitochondrial translation products by SDS gel electrophoresis suggests that 37 degrees-grown [C93] is grossly deficient in the 19,000 Mr subunit of the oligomycin-sensitive ATPase relative to other mitochondrially-synthesized proteins. The ATPase defect was not found in other extranuclear or nuclear mutants deficient in mitochondrial protein synthesis. These data and additional evidence suggest that the primary defect in [C93] may be in the assembly of the ATPase complex. The possible connection between the ATPase defect and the deficiency of mitochondrial protein synthesis is discussed.

Escherichia coli K-12 deficient in galactose-1-phosphate uridyl transferase is capable of converting significant amounts of d-[1-(14)C]galactose to (14)CO(2), whereas strains deficient in other enzymes of the Leloir pathway cannot do so.

A quantitative microbial assay was used to study the stability of known mutagenic and carcinogenic compounds in cell culture medium. Ten direct-acting carcinogens, when incubated in culture medium with 15% fetal bovine serum at pH 7.2-7.4 and 37 degrees C, became inactive at varying rates. Biologic half-lives of the test compounds ranged from 8 minutes to 67 hours. In contrast, six procarcinogens showed no significant inactivation after 3 weeks' incubation. The biologic half-lives of each compound were presented, and the significance of these findings as they relate to cell culture carcinogenesis and mutagenesis assays was discussed.

Leucine-starved mice placed on a diet supplemented with the immediate precursor of leucine, alpha-ketoisocaproic acid, regain lost weight. This weight gain is similar to that observed when the leucine-starved mice are provided with leucine in their diet. Mice on a leucine-free diet supplemented with alpha-ketoisovaleric acid, the first compound in the leucine biosynthetic pathway, continued to lose weight as quickly as mice on leucine-deficient diets.

In Neurospora, one protein associated with the mitochondrial small ribosomal subunit (S-5, Mr 52,000) is synthesized intramitochondrially and is assumed to be encoded by mtDNA. When mitochondrial protein synthesis is inhibited, either by chloramphenicol or by mutation, cells accumulate incomplete mitochondrial small subunits (CAP-30S and INC-30S particles) that are deficient in S-5 and several other proteins. To gain additional insight into the role of S-5 in mitochondrial ribosome assembly, the structures of Neurospora mitochondrial ribosomal subunits, CAP-30S particles, and INC-30S particles were analyzed by equilibrium centrifugation in CsCl gradients containing different concentrations of Mg+2. The results show (a) that S-5 is tightly associated with small ribosomal subunits, as judged by the fact that it is among the last proteins to be dissociated in CsCl gradients as the Mg+2 concentration is decreased, and (b) that CAP-30S and INC-30S particles, which are deficient in S-5, contain at most 12 proteins that are bound as tightly as in mature small subunits. The CAP-30S particles isolated from sucrose gradients contain a number of proteins that appear to be loosely bound, as judged by dissociation of these proteins in CsCl gradients under conditions in which they remain associated with mature small subunits. The results suggest that S-5 is required for the stable binding of a subset of small subunit ribosomal proteins.

Recent results with Neurospora crassa show that one protein (S-5, mol wt 52,000) associated with the mitochondrial (mit) small ribosomal subunit is translated within the mitochondria (Lambowitz et al. 1976. J. Mol. Biol. 107:223-253). In the present work, Neurospora mit ribosomal proteins were analyzed by two-dimensional gel electrophoresis using a modification of the gel system of Mets and Bogorad. The results show that S-5 is present in near stoichiometric concentrations in high salt (0.5 MKCl)-washed mit small subunits from wild-type strains. S-5 is among the most basic mit ribosomal proteins (pI greater than 10) and has a high affinity for RNA under the conditions of the urea-containing gel buffers. The role of S-5 in mit ribosome assembly was investigated by an indirect method, making use of chloramphenicol to specifically inhibit mit protein synthesis. Chloramphenicol was found to rapidly inhibit the assembly of mit small subunits leading to the formation of CAP-30S particles which sediment slightly behind mature small subunits (LaPolla and Lambowitz. 1977. J. Mol. 116: 189-205). Two-dimensional gel analysis shows that the more slowly sedimentaing CAP-30S particles are deficient in S-5 and in several other proteins, whereas these proteins are present in normal concentrations in mature small subunits from the same cells. Because S-5 is the only mit ribosomal protein whose synthesis is directly inhibited by chloramphenicol, the results tentatively suggest that S-5 plays a role in the assembly of mit small subunits. In addition, the results are consistent with the idea that S-5 stabilizes the binding of several other mit small subunit proteins. Two-dimensional gel electrophoresis was used to examine mit ribosomal proteins from [poky] and six additional extra-nuclear mutants with defects in the assembly of mit small subunits. The electrophoretic mobility of S-5 is not detectably altered in any of the mutants. However, [poky] mit small subunits are deficient in S-5 and also contain several other proteins in abnormally low or high concentrations. These and other results are consistent with a defect in a mit ribosomal constituent in [poky].

Clones coding for the mouse nicotinic acetylcholine receptor (AChR) gamma subunit precursor have been selected from a cDNA library derived from a mouse myogenic cell line and sequenced. The deduced protein sequence consists of a signal peptide of 22 amino acid residues and a mature gamma subunit of 497 amino acid residues. There is a high degree of sequence conservation between this mouse sequence and published human and calf AChR gamma subunits and, after allowing for functional amino acid substitutions, also to the more distantly related chicken and Torpedo AChR gamma subunits. The degree of sequence conservation is especially high in the four putative hydrophobic membrane spanning regions, supporting the assignment of these domains. RNA blot hybridization showed that the mRNA level of the gamma subunit increases by 30 fold or more upon differentiation of the two mouse myogenic cell lines, BC3H-1 and C2C12, suggesting that the primary controls for changes in gene expression during differentiation are at the level of transcription. One cDNA clone was found to correspond to a partially processed nuclear transcript containing two as yet unspliced intervening sequences.

A mouse cDNA clone has been isolated that contains the complete coding region of a protein highly homologous to the delta subunit of the Torpedo acetylcholine receptor (AcChoR). The cDNA library was constructed in the vector lambda 10 from membrane-associated poly(A)+ RNA from BC3H-1 mouse cells. Surprisingly, the delta clone was selected by hybridization with cDNA encoding the gamma subunit of the Torpedo AcChoR. The nucleotide sequence of the mouse cDNA clone contains an open reading frame of 520 amino acids. This amino acid sequence exhibits 59% and 50% sequence homology to the Torpedo AcChoR delta and gamma subunits, respectively. However, the mouse nucleotide sequence has several stretches of high homology with the Torpedo gamma subunit cDNA, but not with delta. The mouse protein has the same general structural features as do the Torpedo subunits. It is encoded by a 3.3-kilobase mRNA. There is probably only one, but at most two, chromosomal genes coding for this or closely related sequences.

In Neurospora, the gene encoding the mitochondrial large subunit (25 S) rRNA contains an intervening sequence of approximately 2.3 kilobases. We have recently identified two temperature-sensitive, nuclear mutants (289-67 and 299-9) which are defective in splicing of the 25 S RNA. When grown at the nonpermissive temperature (37 degrees C), the mutants show decreased ratios of 25 S/19 S RNA and accumulate a novel 35 S RNA which appears to be a continuous transcript of the 25 S RNA gene, including the intervening sequence. In the present work, mitochondrial ribonucleoprotein particles present in the 50 S subunit peak from wild type and mutant 299-9 were analyzed by equilibrium centrifugation in CsCl gradients containing 25 mM MgCl2. The results show that 35 S RNA can be isolated as part of a ribonucleoprotein particle associated with nearly all of the large subunit ribosomal proteins. However, the particles appear to be less stable in CsCl gradients and more sensitive to nucleolytic degradation than particles derived from mature large subunits. Our results indicate that binding of ribosomal proteins to 35 S RNA could precede removal of the intron, but that removal of the intron may be required to achieve stable protein binding.

In Neurospora, one mitochondrial ribosomal protein (S-5, Mr = 52,000) is synthesized intramitochondrially and is presumably encoded by mitochondrial DNA. We have developed a rapid method for the purification of S-5 which takes advantage of its high affinity for carboxymethyl-Sepharose in the presence of 6 M urea. Using this method, S-5, at purity greater than 95%, can be prepared by column chromatography in a single batch elution step. The amino acid composition of S-5 was determined. Judged by the contents of hydrophilic and basic amino acids, S-5 is more similar to Escherichia coli and yeast ribosomal proteins than to other mitochondrial translation products which are hydrophobic membrane proteins.