FGF21 as Modulator of Metabolism in Health and Disease

Fibroblast growth factor 21 (FGF21) is a hormone that regulates important metabolic pathways. FGF21 is expressed in several metabolically active organs and interacts with different tissues. The FGF21 function is complicated and well debated due to its different sites of production and actions. Striated muscles are plastic tissues that undergo adaptive changes within their structural and functional properties in order to meet their different stresses, recently, they have been found to be an important source of FGF21. The FGF21 expression and secretion from skeletal muscles happen in both mouse and in humans during their different physiological and pathological conditions, including exercise and mitochondrial dysfunction. In this review, we will discuss the recent findings that identify FG21 as beneficial and/or detrimental cytokine interacting as an autocrine or endocrine in order to modulate cellular function, metabolism, and senescence

The role of age, sex, anthropometry, and body composition as determinants of physical fitness in nonobese children aged 6\u201312

PURPOSE: The determinants of physical fitness in children have been given limited attention. In particular, the relative role of chronological age, sex, anthropometry, and body composition in physical fitness of children has been barely investigated. This cross-sectional study investigated determinants of physical fitness using a set of predictive variables including, in addition to chronological age and sex, a large panel of anthropometric measurements as well as body composition. The study was carried out in a convenience sample of children aged 6\u201312 participating in a summer camp. METHODS: One-hundred-ninety-three children (128 males) fulfilled all requirements and entered analysis. Health-related physical fitness components (speed, muscular power and balance) were explored by means of field tests, namely the 30-m dash test for running speed, the standing long jump and the seated chest pass test for lower limbs and upper body muscular power, respectively, and the flamingo balance test for static balance. Determinants of physical fitness were investigated by regression analysis using chronological age, sex, anthropometry, and body composition in a hierarchical approach. To minimize the expected effect of collinearity in predictor variables, an original statistical approach using Random Forests analysis was adopted. RESULTS: Age predicted 45.2%, 43.6%, 35.6% and 25.6%; and sex 9.5%, 10.7%, 6.3% and 2.0% of variance in the 30-m dash, seated chest pass, standing long jump, and flamingo balance test, respectively. Anthropometry and body composition explained a limited or no percentage of variance. The adjusted R2 (root mean square error) was 0.61 (0.31 s), 0.45 (0.32 m), 0.58 (0.15 m) and 0.41 (0.75 logs) for the 30-m dash, seated chest pass, standing long jump, and flamingo balance test, respectively making these models useful when physical fitness tests are not feasible. CONCLUSIONS: We highlighted the respective role of chronological age, sex, anthropometry, and body composition in physical fitness of children in the wide age range 6\u201312 years. Data confirm and expand on previous literature by showing with a strictly conservative statistical approach that chronological age is a main determinant of physical fitness of both boys and girls, sex playing a limited role. The role of anthropometry was even less important, and no role was found for body composition. These findings should be considered when planning/implementing motor development or physical education programs

How to address the study of open primary elections: insights from the Italian case

International audienceThis case presents the research design used by Candidate and Leader Selection, a standing group of the Italian Political Science Association, for investigating open primary elections held to select candidates and party leaders in Italy. The lack of a legal framework that rules primaries raised several research challenges for studying participation in primary elections and for clarifying the features and attitudes of primary voters. A brief introduction summarizes the main research questions concerning the study of primary elections, providing a theoretical framework and empirical definitions as well. The peculiarities of the Italian case study are then detailed, while the core of the piece is devoted to the research protocol description. In particular, this case presents the research strategies implemented for addressing the study of participation in open primary elections by means of exit polls. In particular, this case details the research procedures adopted for the sampling procedures and the coordination of the research teams at the regional level, the training of interviewers for face-to-face interviews, the drafting of the questionnaire, and the practical solution implemented for administering the survey at polling stations

Linear Ramps of Interaction in the Fermionic Hubbard Model

We study the out of equilibrium dynamics of the Fermionic Hubbard Model induced by a linear ramp of the repulsive interaction $U$ from the metallic state through the Mott transition. To this extent we use a time dependent Gutzwiller variational method and complement this analysis with the inclusion of quantum fluctuations at the leading order, in the framework of a $Z_2$ slave spin theory. We discuss the dynamics during the ramp and the issue of adiabaticity through the scaling of the excitation energy with the ramp duration $\tau$. In addition, we study the dynamics for times scales longer than the ramp time, when the system is again isolated and the total energy conserved. We establish the existence of a dynamical phase transition analogous to the one present in the sudden quench case and discuss its properties as a function of final interaction and ramp duration. Finally we discuss the role of quantum fluctuations on the mean field dynamics for both long ramps, where spin wave theory is sufficient, and for very short ramps, where a self consistent treatment of quantum fluctuations is required in order to obtain relaxation.Comment: v2: 19 pages, 14 figures, published versio

Multiphoton Label-Free ex-vivo imaging using a custom-built dual-wavelength microscope with chromatic aberrations compensation

Label-Free Multiphoton Microscopy is a very powerful optical microscopy that can be applied to study samples with no need for exogenous fluorescent probes, keeping the main benefits of a Multiphoton approach, like longer penetration depths and intrinsic optical sectioning, while opening the possibility of serial examinations with different kinds of techniques. Among the many variations of Label-Free MPM, Higher Harmonic Generation (HHG) is one of the most intriguing due to its generally low photo-toxicity, which enables the examination of specimens particularly susceptible to photo-damages. HHG and common Two-Photon Microscopy (TPM) are well-established techniques, routinely used in several research fields. However, they require a significant amount of fine-tuning in order to be fully exploited and, usually, the optimized conditions greatly differ, making them quite difficult to perform in parallel without any compromise on the extractable information. Here we present our custom-built Multiphoton microscope capable of performing simultaneously TPM and HHG without any kind of compromise on the results thanks to two, separate, individually optimized laser sources with full chromatic aberration compensation. We also apply our setup to the examination of a plethora of ex vivo samples in order to prove the significant advantages of our approach

A note on the comparison of some randomized response procedures

Abstract The paper reconsiders and compares some randomized response models in the light of the efficiency/protection criterion. The results show that, despite the assertion of the authors about the superiority of their methods, some procedures are perfectly equivalent to theWarner’s or the Simmons’models. Ourwork extends and generalizes the results of Bhargava and Singh [2002. On the efficiency comparison of certain randomized response strategies. Metrika 55, 191–197] and other authors

Pharmacological strategies in lung cancer-induced cachexia: effects on muscle proteolysis, autophagy, structure, and weakness

Muscle wasting and cachexia are important systemic manifestations of highly prevalent conditions including cancer. Inflammation, oxidative stress, autophagy, ubiquitin-proteasome system, nuclear factor (NF)-kB, and mitogen activated protein kinases (MAPK) are involved in the pathophysiology of cancer cachexia. Currently available treatment is limited and data demonstrating effectiveness in in vivo models are lacking. Our objectives were to explore in respiratory and limb muscles of lung cancer (LC) cachectic mice whether proteasome, NF-kB, and MAPK inhibitors improve muscle mass and function loss through several molecular mechanisms. Body and muscle weights, limb muscle force, protein degradation and the ubiquitin-proteasome system, signaling pathways, oxidative stress and inflammation, autophagy, contractile and functional proteins, myostatin and myogenin, and muscle structure were evaluated in the diaphragm and gastrocnemius of LC (LP07 adenocarcinoma) bearing cachectic mice (BALB/c), with and without concomitant treatment with NF-kB (sulfasalazine), MAPK (U0126), and proteasome (bortezomib) inhibitors. Compared to control animals, in both respiratory and limb muscles of LC cachectic mice: muscle proteolysis, ubiquitinated proteins, autophagy, myostatin, protein oxidation, FoxO-1, NF-kB and MAPK signaling pathways, and muscle abnormalities were increased, while myosin, creatine kinase, myogenin, and slow- and fast-twitch muscle fiber size were decreased. Pharmacological inhibition of NF-kB and MAPK, but not the proteasome system, induced in cancer-induced cachectic animals, a substantial restoration of muscle mass and force through a decrease in muscle protein oxidation and catabolism, myostatin, and autophagy, together with a greater content of myogenin, and contractile and functional proteins. These findings may offer new therapeutic strategies in cancer-induced cachexia.Fil: Chacon Cabrera, Alba. Universitat Pompeu Fabra; España. Universidad Carlos III de Madrid. Instituto de Salud; EspañaFil: Fermoselle, Clara. Universitat Pompeu Fabra; España. Universidad Carlos III de Madrid. Instituto de Salud; EspañaFil: Urtreger, Alejandro Jorge. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Mateu Jimenez, Mercè. Universidad Carlos III de Madrid. Instituto de Salud; España. Universitat Pompeu Fabra; EspañaFil: Diament, Miriam. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; ArgentinaFil: Bal, Elisa Dora. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Sandri, Marco. Università di Padova; ItaliaFil: Barreiro, Eshter. Universitat Pompeu Fabra; España. Universidad Carlos III de Madrid. Instituto de Salud; Españ