Topical corticosteroids are the recommended first-line treatment for all severities of persistent asthma and moderate to severe allergic rhinitis. Potential adrenal suppression resulting from corticosteroid administration necessitates monitoring of children participating in clinical studies. Measurement of pretreatment cortisol concentrations is necessary to assess effects on adrenal function.Plasma cortisol concentrations are assay dependent; normal reference range values must be obtained for each assay. Our objective is to provide these values for children as determined by HPLC.Two multicenter, randomized, double-blind, placebo-controlled studies evaluating basal and cosyntropin-stimulated morning plasma cortisol concentrations for patients aged 5 to younger than 12 months with asthma and patients aged 2 to younger than 6 yr with allergic rhinitis using HPLC were conducted.Main planned outcomes of these studies are reported elsewhere. This manuscript reports plasma cortisol concentration reference range values.In general, mean basal plasma cortisol concentrations (n = 177) (mean +/- sd, nmol/liter) were similar among the 5 to younger than 9 months, 9 to younger than 12 months, 2 to younger than 3 yr, 3 to younger than 4 yr, 4 to younger than 5 yr, and 5 to younger than 6 yr age groups (218 +/- 149, 281 +/- 144, 257 +/- 105, 231 +/- 83, 298 +/- 118, and 237 +/- 65, respectively) and increased to comparable levels 60 min after cosyntropin stimulation (n = 178; 622 +/- 176, 638 +/- 176, 697 +/- 99, 655 +/- 103, 662 +/- 113, and 610 +/- 68, respectively). However, patients younger than 12 months had wider ranges of basal and stimulated values.Basal and cosyntropin-stimulated morning plasma cortisol concentrations of children aged 5 to younger than 12 months and 2 to younger than 6 yr were consistently measurable, with the large majority similar among the age groups examined, and comparable with those reported elsewhere for adults.
Accurate modeling of the behavior of reinforced concrete components is necessary for obtaining reliable predictions of global response and local demands. This chapter provides context and depth to enable the engineer to exercise judgment in making reasonable modeling assumptions and in evaluating results of such models. Post-processing is needed to establish performance relative to acceptance criteria, which are usually specified in terms of plastic rotations at discrete plastic hinges. Acceptance criteria values must be regarded with a degree of uncertainty, and can be expected to improve as nonlinear assessment becomes more common. Since most experiments are conducted quasi-statically, the question of strain rate effect is sometimes raised. Reinforced concrete members exhibit higher stiffness and strength when loaded rapidly. The inelastic response of beams, columns, and walls is often represented using elements based either on lumped plasticity or distributed plasticity formulations.
Purpose of review The mechanism of puberty initiation remains an enigma, despite extensive research in the field. Pulsatile pituitary gonadotropin secretion under the guidance of hypothalamic gonadotropin-releasing hormone (GnRH) constitutes a sine qua non for pubertal onset. In turn, the secretion of GnRH in the human hypothalamus is regulated by kisspeptin and its receptor as well as by permissive or opposing signals mediated by neurokinin B and dynorphin acting on their respective receptors. These three supra-GnRH regulators compose the Kisspeptin, Neurokinin B and Dynorhin neurons (KNDy) system, a key player in pubertal onset and progression. Recent findings The recent discovery that makorin ring finger protein 3 is also involved in puberty initiation provided further insights into the regulation of the KNDy pathway. In fact, the inhibitory (γ-amino butyric acid, neuropeptide Y, and RFamide-related peptide-3) and stimulatory signals (glutamate) acting upstream of KNDy called into question the role of makorin ring finger protein 3 as the gatekeeper of puberty. Meanwhile, the findings that ‘neuroestradiol’ produced locally and endocrine disruptors from the environment may influence GnRH secretion is intriguing. Finally, epigenetic mechanisms have been implicated in pubertal onset through recently discovered mechanisms. Summary The exact molecular machinery underlying puberty initiation in humans is under intensive investigation. In this review, we summarize research evidence in the field, while emphasizing the areas of uncertainty and underlining the impact of current information on the evolving theory regarding this fascinating phenomenon.
Suicides as well as suicidal behaviours are considered to be one of the main health problems in the world, rated as the second most common cause of death among young people globally and the 15th leading cause of death worldwide among all populations (World Health Organization, 2012). According to statistical data and epidemiological reports, in Europe suicide is the second leading cause of death among people 15 to 29 years old (Blum & Nelson-Mmari, 2004), while in a study by Kokkevi, Rotsika, Arapaki, and Richardson (2011) among Greek adolescents throughout a period of 23 years (1984–2007), self-reported suicide attempts doubled in prevalence from 7.0% to 13.4%.
γH2AX has emerged in the last 20 years as a central player in the DDR (DNA damage response), with specificity for DSBs (double-strand breaks). Upon the generation of DSBs, γ-phosphorylation extends along megabase-long domains in chromatin, both sides of the damage. The significance of this mechanism is of great importance; it depicts a biological amplification mechanism where one DSB induces the γ-phosphorylation of thousands of H2AX molecules along megabaselong domains of chromatin, that are adjusted to the sites of DSBs. A sequential recruitment of signal transduction factors that interact to each other and become activated to further amplify the signal that will travel to the cytoplasm take place on the γ-phosphorylated chromatin. γ-phosphorylation is an early event in the DSB damage response, induced in all phases of the cell cycle, and participates in both DSB repair pathways, the HR (homologous recombination) and NHEJ (non-homologous end joining). Today, numerous studies support the notion that γH2AX functions as a guardian of the genome by preventing misrepaired DSB that increase the mutation load of the cells and may further lead to genome instability and carcinogenesis.
