1,830 research outputs found
Inhibition of phosphoinositide 3-kinase/protein kinase B signaling hampers the vasopressin-dependent stimulation of myogenic differentiation
Arginine-vasopressin (AVP) promotes muscle differentiation, hypertrophy, and regeneration through the combined activation of the calcineurin and Calcium/Calmodulin-dependent Protein Kinase (CaMK) pathways. The AVP system is impaired in several neuromuscular diseases, suggesting that AVP may act as a physiological factor in skeletal muscle. Since the Phosphoinositide 3-kinases/Protein Kinase B/mammalian Target Of Rapamycin (PI3K/Akt/mTOR) signaling plays a significant role in regulating muscle mass, we evaluated its role in the AVP myogenic effect. In L6 cells AKT1 expression was knocked down, and the AVP-dependent expression of mTOR and Forkhead box O3 (FoxO) was analyzed by Western blotting. The effect of the PI3K inhibitor LY294002 was evaluated by cellular and molecular techniques. Akt knockdown hampered the AVP-dependent mTOR expression while increased the levels of FoxO transcription factor. LY294002 treatment inhibited the AVP-dependent expression of Myocyte Enhancer Factor-2 (MEF2) and myogenin and prevented the nuclear translocation of MEF2. LY294002 also repressed the AVP-dependent nuclear export of histone deacetylase 4 (HDAC4) interfering with the formation of multifactorial complexes on the myogenin promoter. We demonstrate that the PI3K/Akt pathway is essential for the full myogenic effect of AVP and that, by targeting this pathway, one may highlight novel strategies to counteract muscle wasting in aging or neuromuscular disorders
Microwave broadband characterization of aging of SU-8 polymer as CPW substrate
In this paper we present the methodology and the
numerical results related to the analysis of aging of the SU-
8 polymer when used as a primary layer for the realization
of Coplanar Waveguide (CPW) structures. As test devices,
we used a set of transmission lines with different lengths and
T-shaped open stubs shunt resonators; by using these
geometries, we are able to acquire the data in a broadband
range, in principle between 1 GHz and 40 GHz. We conduct
the analysis by comparing two different technology run: the
first wafer with a deposited layer by a 12-year-old SU-8 and
the second wafer, with the same photolithographed metallic
geometries, with a brand-new processed SU-8 photoresist
The sustainable reuse of compost from a new type of olive mill pomace in replacing peat for potted olive tree
The attention for the replacement of peat in growing substrates is increasing due to its
environmental and economic advantages. The aim of the present work was to evaluate the impact
of peat substitution by new type olive mill pomace and its compost on the vegetative activity of
potted olive trees. A new type of humid pomace (hP) derived from an innovative two phase
extraction system and its derived compost (C-hP) are used as total or partial (50% vol/vol)
replacement of peat in olive growing substrate. The main chemical characteristics (moisture,
water extractable organic carbon, total nitrogen, C/N ratio and electrical conductivity) of the hP
and C-hP were measured. In order to evaluate the effects of the peat substitution on the plants
vegetative activity, measurements of mortality, plant height, leaf net photosynthesis and plant
growth (through final destructive measurements) were carried out. The use of hP resulted in a
significant increase of the salinity of the substrate. The water extractable organic carbon
concentration was higher in all substrates where peat was ewplaced and in particular when C-hP
was used. The total replacement of peat with hP caused 100% mortality of the plants while C-hP
can substitute peat up to 50% without causing a significative reduction of the final plant growth
Design optimization of meta-material transmission lines for linear and non-linear microwave signal processing
The possibility to use CRLH (Composite Right-/Left-Handed) cells to realize both distributed wide-band filters for linear signal processing and non-linear devices like frequency doublers is investigated analytically and numerically. Full-wave electromagnetic simulations are performed for the filtering structure by means of a commercial software package and confirm the validity of the analytic results. Numerical results for CRLH NLTL (Non-Linear Transmission Line) obtained by using the Microwave Office are discussed, providing design considerations about the synthesis of such a component
Cockayne syndrome group A protein localizes at centrosomes during mitosis and regulates Cyclin B1 ubiquitination
Mutations in CSA and CSB proteins cause Cockayne syndrome, a rare genetic neurodevelopment disorder. Alongside their demonstrated roles in DNA repair and transcription, these two proteins have recently been discovered to regulate cytokinesis, the final stage of the cell division. This last finding allowed, for the first time, to highlight an extranuclear localization of CS proteins, beyond the one already known at mitochondria. In this study, we demonstrated an additional role for CSA protein being recruited at centrosomes in a strictly determined step of mitosis, which ranges from pro-metaphase until metaphase exit. Centrosomal CSA exerts its function in specifically targeting the pool of centrosomal Cyclin B1 for ubiquitination and proteasomal degradation. Interestingly, a lack of CSA recruitment at centrosomes does not affect Cyclin B1 centrosomal localization but, instead, it causes its lasting centrosomal permanence, thus inducing Caspase 3 activation and apoptosis. The discovery of this unveiled before CSA recruitment at centrosomes opens a new and promising scenario for the understanding of some of the complex and different clinical aspects of Cockayne Syndrom
Blind modulation format identification using nonlinear power transformation
This paper proposes and experimentally demonstrates a blind modulation format identification (MFI) method delivering high accuracy (> 99%) even in a low OSNR regime (< 10 dB). By using nonlinear power transformation and peak detection, the proposed MFI can recognize whether the signal modulation format is BPSK, QPSK, 8-PSK or 16-QAM. Experimental results demonstrate that the proposed MFI can achieve a successful identification rate as high as 99% when the incoming signal OSNR is 7 dB. Key parameters, such as FFT length and laser phase noise tolerance of the proposed method, have been characterized
A simple and low-power optical limiter for multi-GHz pulse trains
We study the limiting-amplification capability of a saturated Semiconductor Optical Amplifier (SOA) followed by an optical band-pass filter. We experimentally demonstrate that this simple optical circuit can be effectively exploited to realize a low-power optical limiter for amplitude-modulated pulse trains at multi-GHz repetition rate. We report very large amplitude-modulation-reduction factors for the case of 20 and 40 GHz pulse trains that are super-imposed with modulating frequencies ranging from 100kHz to several GHz. (C) 2007 Optical Society of America
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