Degenerative Myelopathy in Hovawart Dogs: Molecular Characterization, Pathological Features and Accumulation of Mutant Superoxide Dismutase 1 Protein

Degenerative myelopathy (DM) is an adult-onset, progressive neurological disease affecting several breeds of dog. Homozygosity or compound heterozygosity for the canine superoxide dismutase 1 (SOD1) gene mutations, possibly modulated by the modifier SP110 locus, are associated with a high risk for DM. Although the pathophysiological mechanisms are largely unknown, a role for mutant SOD1 in causing neuronal degeneration has been postulated. Three Hovawart dogs, 9e12 years of age, developed slowly progressive incoordination and weakness of the pelvic limbs leading to non-ambulatory flaccid paraparesis and muscle atrophy. Neuropathological lesions comprised axonal degeneration and loss of ascending and descending spinal pathways, which were most severe in the mid- to caudal thoracic segments. Accumulation of mutant SOD1 protein in neurons and reactive astrocytes was demonstrated by immunolabelling with the 16G9 antibody against the mutant SOD1 protein (p.E40K amino acid substitution). All three dogs were homozygous for the c.118A allele, but none had the SP110 ‘risk’ haplotype, suggesting a weak association of SP110 with the onset of DM in this breed. Our data suggest that the Hovawart breed is predisposed to the SOD1:c.118G>A mutation, which is associated with the development of DM. Prevention of DM could be achieved with the help of strategies based on epidemiological and genetic testing

Effect of rMnSOD on sodium reabsorption in renal proximal tubule in Ochratoxin A - treated rats

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium that represent toxic real threat for human beings and animal health. In this study we evaluated the effect of a new recombinant mitochondrial manganese containing superoxide dismutase (rMnSOD) on oxidative stress and on the alterations of fluid reabsorption in renal proximal tubule (PT) as possible causes of OTA nephrotoxicity. Finally, we have measured the concentration of O2 - in the kidney through dihydroethidium assay (DHE) and nitric oxide (NO) concentration through nitrites and nitrates assay. Male Sprague Dawley rats weighing 120-150 g were treated for 14 days by gavage, as follows: Control group, 12 rats received a corresponding amount of saline solution (including 10% DMSO); rMnSOD group, 12 rats treated with rMnSOD (10 μg/kg bw); OTA group, 12 rats treated with OTA (0,5 mg/Kg bw) dissolved in 10% DMSO and then scaled to required volume with corn oil; rMnSOD + OTA, 12 rats treated with rMnSOD (10 μg /kg bw) plus OTA (0,5 mg/Kg bw). Our results have shown that rMnSOD restores the alteration of reabsorption in PT in rats treated with OTA plus rMnSOD, probably through the response to pressure natriuresis, where nitric oxide plays a key role. Moreover, rMnSOD prevents the nephrotoxicity induced by OTA probably restoring the balance between superoxide and NO that is most probably the cause of hypertension and renal functional alterations through the inhibition of NO synthase. In conclusion these data provide important information for understanding of mechanism of toxic action of OTA

HDAC class I inhibitor domatinostat sensitizes pancreatic cancer to chemotherapy by targeting cancer stem cell compartment via FOXM1 modulation

Pancreatic ductal adenocarcinoma (PDAC) represents an unmet clinical need due to the very poor prognosis and the lack of effective therapy. Here we investigated the potential of domatinostat (4SC-202), a new class I histone deacetylase (HDAC) inhibitor, currently in clinical development, to sensitize PDAC to first line standard gemcitabine (G)/taxol (T) doublet chemotherapy treatment. Methods: Synergistic anti-tumor effect of the combined treatment was assessed in PANC1, ASPC1 and PANC28 PDAC cell lines in vitro as well as on tumor spheroids and microtissues, by evaluating combination index (CI), apoptosis, clonogenic capability. The data were confirmed in vivo xenograft models of PANC28 and PANC1 cells in athymic mice. Cancer stem cells (CSC) targeting was studied by mRNA and protein expression of CSC markers, by limiting dilution assay, and by flow cytometric and immunofluorescent evaluation of CSC mitochondrial and cellular oxidative stress. Mechanistic role of forkhead box M1 (FOXM1) and downstream targets was evaluated in FOXM1-overexpressing PDAC cells. Results: We showed that domatinostat sensitized in vitro and in vivo models of PDAC to chemotherapeutics commonly used in PDAC patients management and particularly to GT doublet, by targeting CSC compartment through the induction of mitochondrial and cellular oxidative stress. Mechanistically, we showed that domatinostat hampers the expression and function of FOXM1, a transcription factor playing a crucial role in stemness, oxidative stress modulation and DNA repair. Domatinostat reduced FOXM1 protein levels by downregulating mRNA expression and inducing proteasome-mediated protein degradation thus preventing nuclear translocation correlated with a reduction of FOXM1 target genes. Furthermore, by overexpressing FOXM1 in PDAC cells we significantly reduced domatinostatinducing oxidative mitochondrial and cellular stress and abolished GT sensitization, both in adherent and spheroid cells, confirming FOXM1 crucial role in the mechanisms described. Finally, we found a correlation of FOXM1 expression with poor progression free survival in PDAC chemotherapy-treated patients

Vitiligo: Unmet Need, Management and Treatment Guidelines

Vitiligo is a chronic depigmenting disorder characterized by characteristic, non-scaly, chalky-white skin macules and patches, due to the loss of skin pigment. Its exact pathogenesis is still not fully un-derstood but it seems to be an autoimmune disease where the combination of genetic, environmental, and immune factors contributes to the destruction of melanocytes in the epidermis. Vitiligo is classified into different types based on its clinical characteristics and distribution patterns. The two main forms of vitiligo are non-segmental vitiligo (NSV) and segmental vitiligo (SV). NSV is the predominant form, characterized by symmetrical skin patches, that tend to evolve over time. In contrast, SV has unilateral or band-shaped lesions that progress rapidly but often stabilize early. Herein, current unmet needs in terms of psychosocial consequences and relative lack of valid therapeutic approaches are critically analyzed and put in perspective in the Italian prescribing scenario. Finally, available management guidelines are illustrated and briefly compared, to provide context for upcoming treatment options

Image resection and heat transfer measurements by IR thermography in hypersonic flows

This study describes a data reduction technique to estimate heat fluxes in hypersonic flows based on measurements of the temperature distribution on the surface of the model by means of infrared (IR) thermography. IR images are registered using a camera model based on perspective projection approach taking into account lens distortion. Relative displacements between model and IR camera, due to sting mechanical vibrations, can increase the noise. An approach to reduce it, based on single-step discrete Fourier transform and Speed-Up Robust Features methods, is presented. Heat flux is computed with an inverse heat transfer problem applying the trust region reflective algorithm. The proposed data reduction technique is numerically validated and applied to an experimental test carried out in the Hypersonic Test Facility Delft (HTFD) at Mach number equal to 7.5

On the flow organization of a chevron synthetic jet

In the present study, the flow fields generated by two synthetic jets with a chevron and a conventional circular nozzle exits are studied and compared. For both configurations, the devices are operated at the same input electrical power, thus leading to Reynolds and Strouhal numbers equal to 5600 and 0.115 (for the circular exit) and 6000 and 0.106 (for the chevron exit). Phase-locked stereoscopic particle image velocimetry measurements are used to reconstruct the three-dimensional coherent vortex structures. Time-averaged and phase-averaged mean and turbulent statistics are analysed and discussed. The flow field strongly depends on the exit geometry. In presence of the chevron exit, the conventional vortex ring issued through the circular nozzle exit, is replaced by a non-circular vortex ring with additional streamwise vortices. The mutual interaction between these structures prevents the axis-switching of the non-circular vortex ring during its convection. These streamwise vortices disappear convecting downstream and the vortex ring assumes a circular shape. Comparing the two configurations, the chevron exit generates a larger time-averaged streamwise velocity along the centreline but with lower turbulent kinetic energy intensity. Differences are also present between the notch and the apex planes of the chevron exit. In the notch plane, both the time-averaged axial velocity component profile in the spanwise direction and the shearlayer width are wider than in the apex plane. Furthermore, the presence of the streamwise vortices causes a flow motion towards the jet axis in the apex plane and an opposite motion in the notch plane

Jitter Minimization in Digital PLLs with Mid-Rise TDCs

This paper analyzes the absolute jitter performance of digital phase-locked loops and compares the case when either a multi-bit time-to-digital converter with mid-rise characteristic or a bang-bang phase detector is adopted. The linear equivalent model of the PLL and expressions for random-noise and limit-cycle jitter are first derived for the case of a 2-bit time-to-digital converter with a mid-rise characteristic, and the optimal TDC resolution is determined. The analysis, which account for TDC mismatches, shows that, compared to the 1-bit one, the 2-bit time-to-digital converter can substantially reduce the quantization noise in the case of dominant random-walk noise at the TDC input. Moving to the Nb-bit midrise TDC case, the quantization noise can be further reduced at the cost of higher complexity and finer time resolution. The choice of Nb=2 seems to be the best compromise between jitter reduction and complexity increase. Time-domain simulations assess the theoretical framework and demonstrate the validity of the assumptions made throughout the paper