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Puberty is a critical process characterized by several physical and psychological changes that culminate in the achievement of sexual maturation and fertility. The onset of puberty depends on several incompletely understood mechanisms that certainly involve gonadotropin-releasing hormone (GnRH) and its effects on the pituitary gland. The role of makorin ring finger protein 3 (MKRN3) in the regulation of pubertal timing was revealed when loss-of-function mutations were identified in patients with central precocious puberty (CPP), which to date, represent the most commonly known genetic cause of this condition. The MKRN3 gene showed ubiquitous expression in tissues from a broad spectrum of species, suggesting an important cellular role. Its involvement in the initiation of puberty and endocrine functions has just begun to be studied. This review discusses some of the recent approaches developed to predict MKRN3 functions and its involvement in pubertal development.

Supplementary table and figures for 'GROWTH HORMONE RECEPTOR (GHR) 6Ω PSEUDOEXON ACTIVATION - A NOVEL CAUSE OF SEVERE GROWTH HORMONE INSENSITIVITY (GHI)' manuscript by Cottrell et al.docx. This manuscript describes a novel GHR 6Ω pseudoexon inclusion resulting in a loss of GHR function consistent with a severe Growth Hormone Insensitivity phenotype. This represents a novel mechanism of Laron syndrome and is the first deep intronic variant identified causing severe postnatal growth failure.

Phototherapy was applied to treat medical conditions since 3,500 years, when the ancient Egyptians and Indians used sunlight to treat various diseases. It was only with the invention of electric light in the late 19th century that an alternative emerged. From that time on, the use of phototherapy in the medical field grew, techniques were perfected and developed and eventually gained widespread acceptance. To date, over 2000 scientific articles have been published in PubMed focusing on the various physiological effects of red and NIR radiation. These wavelengths of light have been shown to penetrate through human tissues and to locally and systematically influence cell metabolism, cell signalling, inflammatory processes and growth. This treatment is now called "photobiomodulation" (PBM) therapy. Despite the numerous studies reported, variability in irradiation settings and parameters has led to inconsistent outcomes. The greatest lack of knowledge is related to the effects of low wavelengths of blue/green light. Compared to red/NIR light, blue light is used for a limited range of medical applications because of its inhibitory and cytotoxic effects. However blue light effects have rarely been reported in adipogenesis or lipogenesis studies on adipose tissue. Hence, the biomodulatory potential of blue light at 453 nm wavelength was tested on 3T3-L1 cells during and after the differentiation process with respect to adipogenesis/lipogenesis, metabolic processes, cell proliferation and transcriptome changes. PBM using blue light revealed dose dependent effects during preadipocytes 3T3-L1 differentiation. A single irradiation performed at the first day of induction (Day0) led to a slight effect with a reduced lipid accumulation and changes in the expression of adipogenic markers that appeared down-regulated already after one exposure. Also metabolism, reflecting mitochondria activity, was negatively affected by blue light since oxidative phosphorylation and ATP contents were decreased with effects that were long lasting until 24h. Tests with repeated irradiations for all differentiation period showed an enhanced inhibition in lipid accumulation and metabolism. This chronic exposure was supposed to rise the ROS amount leading to DNA damages that have had as consequence a cell cycle delay, reduced proliferation rate and cell death processes. Gene expression analysis supported this hypothesis by an up-regulation of the p53 pathway and for all the other genes involved in repair systems such as ATM, Chk1 and Claspin. The blue light spectrum, being close to the harmful UVs wavelength, seems to induce cell death mediated by oxidative stress and damages accumulation in differentiating preadipocytes. On the other hand mature adipocytes treated with 21.6 j/cm2 or 43.2 j/cm2 of blue light have proven to be less responsive. No significant differences were reported in metabolism, growth and lipid storage. Similarly apoptosis has not been deregulated and no changes in ROS levels or cellular damages have been observed. In conclusion adipocytes seem to be more sensitive to blue light exposure during early rather than in late differentiation phases. Furthermore, the high doses of irradiation chosen led to inhibitory effects on metabolism and differentiation promoting cell death in preadipocytes subjected to chronic exposure while no effects were recorded in irradiated mature adipocytes. The results indicated that an optimal choice of irradiation parameters, particularly the dose or irradiation time, is important. Too high doses can lead to expected inhibitory but also deleterious effects on cells. Though inhibitory effects in adipogenesis or proliferation are requested relating to the treatment of hyperplastic obesity or dysregulation of lipid accumulation during childhood, the formation of aberrant cells has to be avoided. Therefore additional studies are needed to promote or reject blue light application in these fields. If tetraploid or aneuploid cells formation is not observed, blue light could be a possible alternative to pharmacological or surgical solutions in some obese subjects. However, there is currently no evidence of a possible application in hypertrophic obesity condition.

Cells physical properties and functions like adhesion, migration and division are all regulated by an interplay between mechanical and biochemical processes occurring within and across the cell membrane. It is however known that mechanical forces spread through the cytoskeletal elements and reach equilibrium with characteristic times at least one order of magnitude smaller than the ones typically governing propagation of biochemical signals and biological phenomena like polymerization/depolymerization of protein microfilaments or even cell duplication and differentiation. This somehow allows to study as uncoupled many biochemo- mechanical events although they appear simultaneously and as concatenated. In this work, the complex machinery of the cell is hence deprived of its biochemical processes with the aim to bring out the crucial role that mechanics plays in regulating the cell as a whole as well as in terms of some interactions occurring at the interface with the extra-cellular matrix. In this sense, the single-cell is here described as a mechanical unit, endowed with an internal micro-architecture –the cytoskeleton– able to sense extra-cellular physical stimuli and to react to them through coordinated structural remodelling and stress redistribution that obey specific equilibrium principles. By coupling discrete and continuum theoretical models, cell mechanics is investigated from different perspectives, thus deriving the cell overall elastic response as the macroscopic projection of micro-structural kinematics involving subcellular constituents. Finally, some optimal arrangements of adherent cells in response to substrate-mediated elastic interactions with external loads are explored and compared with experimental evidences from the literature.

IntroductionDLK1 gene is considered a molecular gatekeeper of adipogenesis. DLK1 mutations have been reported as a cause of central precocious puberty associated with obesity and metabolic syndrome with undetectable DLK1 serum levels. We investigated the association between DLK1 circulating levels with clinical and biochemical parameters in obese adolescents and healthy controls.MethodsSixty-five obese adolescents and 40 controls were enrolled and underwent a complete clinical examination and biochemical assessment for glucose homeostasis and DLK1 plasma levels.ResultsWe observed lower DLK1 levels in cases compared to controls. Moreover, we found a negative correlation between DLK1 and HOMA-IR and a direct correlation with insulin-sensitivity index.DiscussionOur findings suggest that DLK1 might be involved in metabolic derangement in obese children.

Context Severe forms of growth hormone insensitivity (GHI) are characterized by extreme short stature, dysmorphism, and metabolic anomalies. Objective This work aims to identify the genetic cause of growth failure in 3 “classical” GHI individuals. Methods A novel intronic growth hormone receptor gene (GHR) variant was identified, and in vitro splicing assays confirmed aberrant splicing. A 6Ω pseudoexon GHR vector and patient fibroblast analysis assessed the consequences of the novel pseudoexon inclusion and the impact on GHR function. Results We identified a novel homozygous intronic GHR variant (g.5:42700940T > G, c.618+836T > G), 44 bp downstream of the previously recognized intronic 6Ψ GHR pseudoexon mutation in the index patient. Two siblings also harbored the novel intronic 6Ω pseudoexon GHR variant in compound heterozygosity with the known GHR c.181C > T (R43X) mutation. In vitro splicing analysis confirmed inclusion of a 151-bp mutant 6Ω pseudoexon not identified in wild-type constructs. Inclusion of the 6Ω pseudoexon causes a frameshift resulting in a nonfunctional truncated GHR lacking the transmembrane and intracellular domains. The truncated 6Ω pseudoexon protein demonstrated extracellular accumulation and diminished activation of STAT5B signaling following GH stimulation. Conclusion Novel GHR 6Ω pseudoexon inclusion results in loss of GHR function consistent with a severe GHI phenotype. This represents a novel mechanism of Laron syndrome and is the first deep intronic variant identified causing severe postnatal growth failure. The 2 kindreds originate from the same town in Campania, Southern Italy, implying common ancestry. Our findings highlight the importance of studying variation in deep intronic regions as a cause of monogenic disorders.

Soy-based infant formulas (SFs) are often consumed by cow’s milk allergic children. However, some concerns have risen since soy intake may adversely affect thyroid function in iodine-deficient or subclinical hypothyroid individuals. We report the first Italian case of SF induced goiter and hypothyroidism registered in our country since National Iodine program has been instituted. Finally, we review cases previously reported in literature. A 22-month-old toddler with a previous diagnosis of cow’s milk protein allergy came to clinical attention for important goiter and overt hypothyroidism. Detailed dietary anamnesis revealed that he was on a restrictive dietary regimen based on soymilk since 12 months of age. A temporary levothyroxine substitution was instituted to avoid hypothyroidism complications. Adequate iodine supplementation and diet diversification completely reversed SF-induced hypothyroidism and goiter, confirming the diagnostic suspicion of soymilk-induced thyroid dysfunction in a iodine-deficient toddler. This case report demonstrates the importance of careful dietary habits investigation and adequate micronutrients supplementation in children on a restrictive diet due to multiple food allergies in order to prevent nutritional deficits.

Composites are experiencing a new era. The spatial resolution at which is to date possible to build up complex architectured microstructures through additive manufacturing-based and sintering of powder metals 3D printing techniques, as well as the recent improvements in both filament winding and automated fiber deposition processes, are opening new unforeseeable scenarios for applying optimization strategies to the design of high-performance structures and metamaterials that could previously be only theoretically conceived. Motivated by these new possibilities, the present work, by combining computational methods, analytical approaches and experimental analysis, shows how finite element Design Optimization algorithms can be ad hoc rewritten by identifying as design variables the orientation of the reinforcing fibers in each ply of a layered structure for redesigning fiber-reinforced composites exhibiting at the same time high stiffness and toughening, two features generally in competition each other. To highlight the flexibility and the effectiveness of the proposed strategy, after a brief recalling of the essential theoretical remarks and the implemented procedure, selected example applications are finally illustrated on laminated plates under different boundary conditions, cylindrical layered shells with varying curvature subjected to point loads and composite tubes made of carbon fiber-reinforced polymers, recently employed as structural components in advanced aerospace engineering applications.

Tensegrity systems occur when self-equilibrated states are achieved through the interplay of pretensed (cables) and precompressed (struts) elements. The principles that govern these types of structures have been widely observed in many living systems across the scales and recently recognized, with soft or buckling bars, in the cytoskeleton as well as within single protein architectures as associated with key cellular and subcellular processes. To properly model these mechanical phenomena, some limitations dictated by the mostly linear approaches –used in literature when dealing with tensegrity structures – needto be overcome. To this aim, the present work provides a novel 2-element soft-tensegrity paradigm that includes, for the first time, (neo-Hookean) finite hyperelasticity for cable and strut, the latter potentially undergoing both contraction and buckling at each prestressed equilibrium stage. It is finally shown that constitutive properties, instability and bar deformability cooperate to determine unusual form-finding results, providing peculiar overall mechanical responses as external forces are applied.