A precise new KLOE measurement of ∣Fπ∣2|F_\pi|^2 with ISR events and determination of ππ\pi\pi contribution to aμa_\mu for 0.592<Mππ<0.9750.592 < M_{\pi\pi} < 0.975 GeV

The KLOE experiment at the DA$\Phi$NE $\phi$-factory has performed a new precise measurement of the pion form factor using Initial State Radiation events, with photons emitted at small polar angle. Results based on an integrated luminosity of 240 pb$^{-1}$ and extraction of the $\pi\pi$ contribution to $a_\mu$ in the mass range $0.35< M^2_{\pi\pi}<0.95$ GeV$^2$ are presented. The new value of $a^{\pi\pi}_\mu$ has smaller (30%) statistical and systematic error and is consistent with the KLOE published value (confirming the current disagreement between the standard model prediction for $a_\mu$ and the measured value).Comment: 5 pages, proceedings for the CIPANP 2009 conferenc

Incoherent pion photoproduction on the deuteron in the first resonance region

Incoherent pion photoproduction on the deuteron is studied in the first resonance region. The unpolarized cross section, the beam asymmetry, and the vector and tensor target asymmetries are calculated in the framework of a diagrammatic approach. Pole diagrams and one-loop diagrams with $NN$ scattering in the final state are taken into account. An elementary operator for pion photoproduction on the nucleon is taken in various on-shell forms and calculated using the SAID and MAID multipole analyses. Model dependence of the obtained results is discussed in some detail. A comparison with predictions of other works is given. Although a reasonable description of many available experimental data on the unpolarized total and differential cross sections and photon asymmetry has been achieved, in some cases a significant disagreement between the theory and experiment has been found. Invoking known information on the reactions $\gamma d\to\pi^0 d$ and $\gamma d\to np$ we predict the total photoabsorption cross section for deuterium. We find that our values strongly overestimate experimental data in the vicinity of the $\Delta$ peak.Comment: 22 pages, 23 figure

New Target Genes for the Peroxisome Proliferator-Activated Receptor-γ (PPARγ) Antitumour Activity: Perspectives from the Insulin Receptor

The insulin receptor (IR) plays a crucial role in mediating the metabolic and proliferative functions triggered by the peptide hormone insulin. There is considerable evidence that abnormalities in both IR expression and function may account for malignant transformation and tumour progression in some human neoplasias, including breast cancer. PPARγ is a ligand-activated, nuclear hormone receptor implicated in many pleiotropic biological functions related to cell survival and proliferation. In the last decade, PPARγ agonists—besides their known action and clinical use as insulin sensitizers—have proved to display a wide range of antineoplastic effects in cells and tissues expressing PPARγ, leading to intensive preclinical research in oncology. PPARγ and activators affect tumours by different mechanisms, involving cell proliferation and differentiation, apoptosis, antiinflammatory, and antiangiogenic effects. We recently provided evidence that PPARγ and agonists inhibit IR by non canonical, DNA-independent mechanisms affecting IR gene transcription. We conclude that IR may be considered a new PPARγ “target” gene, supporting a potential use of PPARγ agonists as antiproliferative agents in selected neoplastic tissues that overexpress the IR

Novel triblock co-polymer nanofibre system as an alternative support for embryonic stem cells growth and pluripotency

Conventionally, embryonic stem cells (ESCs) are cultured on gelatin or over a mitotically inactivated monolayer of mouse embryonic fibroblasts (MEFsi). Considering the lack of versatile, non-animal-derived and inexpensive materials for that purpose, we aimed to find a biomaterial able to support ESC growth in a pluripotent state that avoids the need for laborious and time-consuming MEFsi culture in parallel with mouse ESC (mESC) culture. Undifferentiated mESCs were cultured in a new nanofibre material designed for ESC culture, which is based on the self-assembly of a triblock co-polymer, poly(ethyleneglycol-β-trimethylsilyl methacrylate-β-methacrylic acid), conjugated with the peptide glycine-arginine-glycine-aspartate-serine, to evaluate its potential application in ESC research. The morphology, proliferation, viability, pluripotency and differentiation potential of mESCs were assessed. Compared to conventional stem cell culture methodologies, the nanofibres promoted a higher increase in mESCs number, enhanced pluripotency and were able to support differentiation after long-term culture. This newly developed synthetic system allows the elimination of animal-derived matrices and provides an economic method of ESC culture, made of a complex network of nanofibres in a scale similar to native extracellular matrices, where the functional properties of the cells can be observed and manipulated

The cAMP-HMGA1-RBP4 system: a novel biochemical pathway for modulating glucose homeostasis

<p>Abstract</p> <p>Background</p> <p>We previously showed that mice lacking the high mobility group A1 gene (<it>Hmga1</it>-knockout mice) developed a type 2-like diabetic phenotype, in which cell-surface insulin receptors were dramatically reduced (below 10% of those in the controls) in the major targets of insulin action, and glucose intolerance was associated with increased peripheral insulin sensitivity. This particular phenotype supports the existence of compensatory mechanisms of insulin resistance that promote glucose uptake and disposal in peripheral tissues by either insulin-dependent or insulin-independent mechanisms. We explored the role of these mechanisms in the regulation of glucose homeostasis by studying the <it>Hmga1</it>-knockout mouse model. Also, the hypothesis that increased insulin sensitivity in <it>Hmga1</it>-deficient mice could be related to the deficit of an insulin resistance factor is discussed.</p> <p>Results</p> <p>We first show that HMGA1 is needed for basal and cAMP-induced retinol-binding protein 4 (<it>RBP4</it>) gene and protein expression in living cells of both human and mouse origin. Then, by employing the <it>Hmga1</it>-knockout mouse model, we provide evidence for the identification of a novel biochemical pathway involving HMGA1 and the RBP4, whose activation by the cAMP-signaling pathway may play an essential role for maintaining glucose metabolism homeostasis <it>in vivo</it>, in certain adverse metabolic conditions in which insulin action is precluded. In comparative studies of normal and mutant mice, glucagon administration caused a considerable upregulation of HMGA1 and RBP4 expression both at the mRNA and protein level in wild-type animals. Conversely, in <it>Hmga1</it>-knockout mice, basal and glucagon-mediated expression of RBP4 was severely attenuated and correlated inversely with increased <it>Glut4 </it>mRNA and protein abundance in skeletal muscle and fat, in which the activation state of the protein kinase Akt, an important downstream mediator of the metabolic effects of insulin on Glut4 translocation and carbohydrate metabolism, was simultaneously increased.</p> <p>Conclusion</p> <p>These results indicate that HMGA1 is an important modulator of <it>RBP4 </it>gene expression <it>in vivo</it>. Further, they provide evidence for the identification of a novel biochemical pathway involving the cAMP-HMGA1-RBP4 system, whose activation may play a role in glucose homeostasis in both rodents and humans. Elucidating these mechanisms has importance for both fundamental biology and therapeutic implications.</p

Comparison of two rocuronium bromide doses in adult and elderly patients who underwent laparoscopic surgery

Background The aim of our study was to evaluate the effects of two different doses of rocuronium bromide (0.5 mg/kg and 0.9 mg/kg) on the length of neuromuscular block, on the haemodynamic stability and on the side effects in patients of different ages. Methods We recruited 80 patients who underwent laparoscopic surgery (cholecystectomy, appendicectomy, varicocelectomy) belonging to ASA I–II classes and divided them into four groups:• 20 adults (A0.5) who received rocuronium bromide 0.5 mg/kg• 20 elderly patients (E0.5) who received rocuronium bromide 0.5 mg/kg• 20 adults (A0.9) who received rocuronium bromide 0.9 mg/kg• 20 elderly patients (E0.9) who received rocuronium bromide 0.9 mg/kgIntubation conditions, continuous monitoring of HR, NIBP, SpO2, EtCO2 were recorded. Onset time, REC 25%, TOF-ratio 0.70 were analysed by TOF-WATCH.Nerve-evoked muscle tension and neuromuscular paralysis extension were expressed by strength of contraction of adductor pollicis, in response to a direct stimulation of the ulnar nerve (TOF). Results The results showed that in elderly patients the effect of rocuronium bromide, at two different doses, was similar. Significant differences regarding the onset time was found among the groups showing that with the same dose of rocuronium bromide, the onset time was prolonged in elderly patients compared to adult patients. Moreover, increasing the dose, the onset time was reduced in both groups (p < 0.05). Forty per cent of adult group A0.5 showed excellent intubation conditions versus 60% of A0.9 (p < 0.05); elderly patients did not show any significant difference in the intubation procedure after different doses of rocuronium bromide.ConclusionsThe results from the four groups showed that in elderly patients 0.5 mg/kg of rocuronium bromide resulted in a good recovery, while 0.9 mg/kg increased the recovery time. Moreover, in adults the high dose was more effective because it reduced the number of injections and post-operative recovery time

Specific and non-specific biomarkers in neuroendocrine gastroenteropancreatic tumors

The diagnosis of neuroendocrine tumors (NETs) is a challenging task: Symptoms are rarely specific, and clinical manifestations are often evident only when metastases are already present. However, several bioactive substances secreted by NETs can be included for diagnostic, prognostic, and predictive purposes. Expression of these substances differs between different NETs according to the tumor hormone production. Gastroenteropancreatic (GEP) NETs originate from the diffuse neuroendocrine system of the gastrointestinal tract and pancreatic islets cells: These tumors may produce many non-specific and specific substances, such as chromogranin A, insulin, gastrin, glucagon, and serotonin, which shape the clinical manifestations of the NETs. To provide an up-to-date reference concerning the different biomarkers, as well as their main limitations, we reviewed and summarized existing literature

Quasifree pion photoproduction on the deuteron in the Δ\Delta region

Photo production of pions on the deuteron is studied in the spectator nucleon model. The Born terms of the elementary production amplitude are determined in pseudovector $\pi$N coupling and supplied with a form factor. The $\Delta$ resonance is considered both in the $s$ and the $u$ channel. The parameters of the $\Delta$ resonance and the cutoff of the form factors are fixed on the leading photoproduction multipoles. Results for total and differential cross sections are compared with experimental data. Particular attention is paid to the role of Pauli correlations of the final state nucleons in the quasifree case. The results are compared with those for pion photoproduction on the nucleon.Comment: 17 pages LateX2e including 5 postscript figure

A novel mechanism of post-translational modulation of HMGA functions by the histone chaperone nucleophosmin

High Mobility Group A are non-histone nuclear proteins that regulate chromatin plasticity and accessibility, playing an important role both in physiology and pathology. Their activity is controlled by transcriptional, post-transcriptional, and post-translational mechanisms. In this study we provide evidence for a novel modulatory mechanism for HMGA functions. We show that HMGAs are complexed in vivo with the histone chaperone nucleophosmin (NPM1), that this interaction requires the histone-binding domain of NPM1, and that NPM1 modulates both DNA-binding affinity and specificity of HMGAs. By focusing on two human genes whose expression is directly regulated by HMGA1, the Insulin receptor (INSR) and the Insulin-like growth factor-binding protein 1 (IGFBP1) genes, we demonstrated that occupancy of their promoters by HMGA1 was NPM1-dependent, reflecting a mechanism in which the activity of these cis-regulatory elements is directly modulated by NPM1 leading to changes in gene expression. HMGAs need short stretches of AT-rich nucleosome-free regions to bind to DNA. Therefore, many putative HMGA binding sites are present within the genome. Our findings indicate that NPM1, by exerting a chaperoning activity towards HMGAs, may act as a master regulator in the control of DNA occupancy by these proteins and hence in HMGA-mediated gene expression

Synthesis and characterization of hybrid organic-inorganic materials based on sulphonated polyamideimide and silica

The preparation of hybrid organic–inorganic membrane materials based on a sulphonated polyamideimide resin and silica filler has been studied. The method allows the sol–gel process to proceed in the presence of a high molecular weight polyamideimide, resulting in well dispersed silica nanoparticles (<50 nm) within the polymer matrix with chemical bonding between the organic and inorganic phases. Tetraethoxysilane (TEOS) was used as the silica precursor and the organosilicate networks were bonded to the polymer matrix via a coupling agent aminopropyltriethoxysilane (APTrEOS). The structure and properties of these hybrid materials were characterized via a range of techniques including FTIR, TGA, DSC, SEM and contact angle analysis. It was found that the compatibility between organic and inorganic phases has been greatly enhanced by the incorporation of APTrEOS. The thermal stability and hydrophilic properties of hybrid materials have also been significantly improved