Targeting RyR Activity Boosts Antisense Exon 44 and 45 Skipping in Human DMD Skeletal or Cardiac Muscle Culture Models.

Systemic delivery of antisense oligonucleotides (AO) for DMD exon skipping has proven effective for reframing DMD mRNA, rescuing dystrophin expression, and slowing disease progression in animal models. In humans with Duchenne muscular dystrophy treated with AOs, low levels of dystrophin have been induced, and modest slowing of disease progression has been observed, highlighting the need for improved efficiency of human skipping drugs. Here, we demonstrate that dantrolene and Rycals S107 and ARM210 potentiate AO-mediated exon skipping of exon 44 or exon 45 in patient-derived myotube cultures with appropriate mutations. Further, dantrolene is shown to boost AO-mediated exon skipping in patient-derived, induced cardiomyocyte cultures. Our findings further validate the ryanodine receptors (RyR) as the likely target responsible for exon skip boosting and demonstrate potential applicability beyond exon 51 skipping. These data provide preclinical support of dantrolene trial as an adjuvant to AO-mediated exon-skipping therapy in humans and identify a novel Rycal, ARM210, for development as a potential exon-skipping booster. Further, they highlight the value of mutation-specific DMD culture models for basic discovery, preclinical drug screening and translation of personalized genetic medicines

Main Fuel Cells mathematical models: Comparison and analysis in terms of free parameters

This paper resumes the main mathematical models of Fuel Cells (PEM models). In particular, a comparison study of the various models introduced in the technical literature is presented and the dependency of the various model parameters is analyzed in different operating conditions. As the manifold of the model parameter is very wide and their determination is difficult, it is mandatory to introduce approximations and simplifications on which each model is based. The novelty of this work is the organization of the existing models in three categories with regard to the number of free parameters and to the dependency of such parameters on the different running conditions and the usage of a reference model in order to compare the difference between the latter once both in terms of fast execution of the simulation and care of the simulation results

Hypergrowth mTORC1 signals translationally activate the ARF tumor suppressor checkpoint

The ARF tumor suppressor is a potent sensor of hyperproliferative cues emanating from oncogenic signaling. ARF responds to these cues by eliciting a cell cycle arrest, effectively abating the tumorigenic potential of these stimuli. Prior reports have demonstrated that oncogenic Ras(V12) signaling induces ARF through a mechanism mediated by the Dmp1 transcription factor. However, we now show that ARF protein is still induced in response to Ras(V12) in the absence of Dmp1 through the enhanced translation of existing Arf mRNAs. Here, we report that the progrowth Ras/tuberous sclerosis complex (TSC)/mTORC1 signaling pathway regulates ARF protein expression and triggers ARF-mediated tumor suppression through a novel translational mechanism. Hyperactivation of mTORC1 through Tsc1 loss resulted in a significant increase in ARF expression, activation of the p53 pathway, and a dramatic cell cycle arrest, which were completely reversed upon Arf deletion. ARF protein induced from Ras(V12) in the absence of Dmp1 repressed anchorage-independent colony formation in soft agar and tumor burden in an allograft model. Taken together, our data demonstrate the ability of the ARF tumor suppressor to respond to hypergrowth stimuli to prevent unwarranted tumor formation

New insights about the putative role of myokines in the context of cardiac rehabilitation and secondary cardiovascular prevention.

Exercise training prevents the onset and the development of many chronic diseases, acting as an effective tool both for primary and for secondary prevention. Various mechanisms that may be the effectors of these beneficial effects have been proposed during the past decades: some of these are well recognized, others less. Muscular myokines, released during and after muscular contraction, have been proposed as key mediators of the systemic effects of the exercise. Nevertheless the availability of an impressive amount of evidence regarding the systemic effects of muscle-derived factors, few studies have examined key issues: (I) if skeletal muscle cells themselves are the main source of cytokine during exercise; (II) if the release of myokines into the systemic circulation reach an adequate concentration to provide significant effects in tissues far from skeletal muscle; (III) what may be the role carried out by muscular cytokine regarding the well-known benefits induced by regular exercise, first of all the anti-inflammatory effect of exercise. Furthermore, a greater part of our knowledge regarding myokines derives from the muscle of healthy subjects. This knowledge may not necessarily be transferred per se to subjects with chronic diseases implicating a direct or indirect muscular dysfunction and/or a chronic state of inflammation with persistent immune-inflammatory activation (and therefore increased circulating levels of some cytokines): cachexia, sarcopenia due to multiple factors, disability caused by neurological damage, chronic congestive heart failure (CHF) or coronary artery disease (CAD). A key point of future studies is to ascertain how is modified the muscular release of myokines in different categories of unhealthy subjects, both at baseline and after rehabilitation. The purpose of this review is to discuss the main findings on the role of myokines as putative mediators of the therapeutic benefits obtained through regular exercise in the context of secondary cardiovascular prevention

First Measurements with NeXtRAD, a Polarimetric X/L Band Radar Network

NeXtRAD is a fully polarimetric, X/L Band radar network. It is a development of the older NetRAD system and builds on the experience gained with extensive deployments of NetRAD for sea clutter and target measurements. In this paper we will report on the first measurements with NeXtRAD, looking primarily at sea clutter and some targets, as well as early attempts at calibration using corner reflectors, and an assessment of the polarimetric response of the system. We also highlight innovations allowing for efficient data manipulation post measurement campaigns, as well as the plans for the coming years with this system

Simulations of a micro-PET System based on Liquid Xenon

The imaging performance of a high-resolution preclinical microPET system employing liquid xenon as the gamma ray detection medium was simulated. The arrangement comprises a ring of detectors consisting of trapezoidal LXe time projection ionization chambers and two arrays of large area avalanche photodiodes for the measurement of ionization charge and scintillation light. A key feature of the LXePET system is the ability to identify individual photon interactions with high energy resolution and high spatial resolution in 3 dimensions and determine the correct interaction sequence using Compton reconstruction algorithms. The simulated LXePET imaging performance was evaluated by computing the noise equivalent count rate, the sensitivity and point spread function for a point source, and by examining the image quality using a micro-Derenzo phantom according to the NEMA-NU4 standard. Results of these simulation studies included NECR peaking at 1326 kcps at 188 MBq (705 kcps at 184 MBq) for an energy window of 450 - 600 keV and a coincidence window of 1 ns for mouse (rat) phantoms. The absolute sensitivity at the center of the field of view was 12.6%. Radial, tangential, and axial resolutions of 22Na point sources reconstructed with a list-mode maximum likelihood expectation maximization algorithm were <= 0.8 mm (FWHM) throughout the field of view. Hot-rod inserts of < 0.8 mm diameter were resolvable in the transaxial image of a micro-Derenzo phantom. The simulations show that a liquid xenon system would provide new capabilities for significantly enhancing PET images

Effect of defoliation management and plant arrangement on yield and N2 fixation of berseem-annual ryegrass mixture

The research was carried out in a Mediterranean semi-arid environment on berseem clover, annual ryegrass and their mixture to study the effect of defoliation management [date of \ufb01rst cut (FC) 85, 119, 140, 169 days after sowing] and different plant arrangements (sowing the two components in alternate rows or in the same row) on yields, N content, N2 \ufb01xation and N transfer. The experimental design was a split-plot with four replications. The 15 N isotope dilution technique was used (8 kg N ha \u20131 as ammonium sulphate at 10 atom% 15 N excess) to evaluate the N2 \ufb01xation. Total seasonal DM yield was, on average, signi\ufb01cantly higher for FC119 and FC140 (approx. 12.3 t ha \u20131 ) than for FC85 and FC169 (approx. 10.6 t ha \u20131 ). Plant arrangement did not signi\ufb01cantly in\ufb02uence total yield of the mixture. However, the legume yield was higher (+20%; P<0.0001) in the same row than in alternate rows arrangement. N content of ryegrass was signi\ufb01cantly higher in the mixtures than in pure stand and in the \u2018same row\u2019 plant arrangement than in the \u2018alternate rows\u2019. Intercropped berseem always had a signi\ufb01cant higher % of Ndfa than the monocropped one (on average 74.7% and 57.7% respectively). The apparent transfer of \ufb01xed N from berseem to ryegrass was not detected in either plant arrangement

Identification of DHX33 as a mediator of rRNA synthesis and cell growth

In this report, we employed a lentiviral RNA interference screen to discover nucleolar DEAD/DEAH-box helicases involved in RNA polymerase I (Pol I)-mediated transcriptional activity. Our screen identified DHX33 as an important modulator of 47S rRNA transcription. We show that DHX33 is a cell cycle-regulated nucleolar protein that associates with ribosomal DNA (rDNA) loci, where it interacts with the RNA Pol I transcription factor upstream binding factor (UBF). DHX33 knockdown decreased the association of Pol I with rDNA and caused a dramatic decrease in levels of rRNA synthesis. Wild-type DHX33 overexpression, but not a DNA binding-defective mutant, enhanced 47S rRNA synthesis by promoting the association of RNA polymerase I with rDNA loci. In addition, an NTPase-defective DHX33 mutant (K94R) acted as a dominant negative mutant, inhibiting endogenous rRNA synthesis. Moreover, DHX33 deficiency in primary human fibroblasts triggered a nucleolar p53 stress response, resulting in an attenuation of proliferation. Thus, we show the mechanistic importance of DHX33 in rRNA transcription and proliferation

Against the Odds: Psychomotor Development of Children Under 2 years in a Sudanese Orphanage.

Providing abandoned children the necessary medical and psychological care as possible after their institutionalization may minimize developmental delays. We describe psychomotor development in infants admitted to an orphanage in Khartoum, Sudan, assessed at admission and over an 18-month follow-up. Psychological state and psychomotor quotients were determined using a simplified Neonatal Behavior Assessment Scale (NBAS), the Brunet-Lezine and Alarm distress baby (ADBB) scale. From May-September 2005, 151 children were evaluated 2, 4, 9, 12 and 18 months after inclusion. At admission, ∼15% of children ≤1 month had a regulation impairment according to the NBAS, and 33.8% presented a distress state (ADBB score >5). More than 85% (129/151) recovered normal psychomotor development. The results of the program reinforce the importance of early detection of psychological disorders followed by rapid implementation of psychological case management to improve the development of young children in similar institutions and circumstances