Development of an experimental model of a decellularized kidney scaffold by perfusion mode and analyzing the three-dimensional extracellular matrix architecture by edge detection method

Renal transplant is treatment of choice for the patients with end stage renal disease. The kidney transplants are expensive and there are risks of immunological and infectious complications. We planned to develop an in vitro decellularized kidney scaffold model using sheep kidney. Kidney decellularization was carried out by perfusing chemical detergents such as sodium dodecyl sulfate (SDS), SDS and trypsin, and SDS and ethylenediaminetetraacetic acid solvent solution. Complete kidney was decellularized in 5 days by perfusing various chemical detergents in time-dependent intervals. Histological finding revealed the complete removal of cellular material in various regions of renal corpuscle, distal convoluted tubules, other cortex and medulla region. Details of interlobular veins and arteries were seen through naked eyes after trypan blue dye injection. We used edge detection technique for developing a three-dimensional (3-D) image (Image J software) for nephrological vasculature constructed of decellularized kidney scaffold specimen. This technique opens a gateway for the whole organ decellularization by perfusion technology and further imaging of its 3-D extracellular matrix texture by edge detection technique software

Extended high gain observer based control design for buck-boost converters

The evolution of the modern technologies and the development of power electronics has led to the extensive use of DC-DC Buck-Boost converters in the application of power amplifier, battery management system, self-regulating power supplies etc, as they have higher output voltage and low operating duty cycle. The problem of degradation in adeptness of the Buck-Boost converters in presence of a load and lumped parameter uncertainties are analyzed. An Extended High Gain Observer is formulated to estimate the output voltage, load current, and its first derivative which is considered to be nonlinear and bounded. The reference current is compared with the estimated load current, forming a sliding surface. Sliding Mode Controller ensures convergence of estimated load current trajectories to reference current trajectories in finite time. Finally, an inner control loop generates a duty ratio resulting in output voltage which tracks the required reference voltage. The simulation results have been implemented in MATLAB/Simulink to validate fast estimation of load current, output voltage and disturbance rejection in a closed-loop process

In vitro and in vivo studies reveal α-Mangostin, a xanthonoid from Garcinia mangostana, as a promising natural antiviral compound against chikungunya virus

Abstract Background Chikungunya virus (CHIKV), a serious health problem in several tropical countries, is the causative agent of chikungunya fever. Approved antiviral therapies or vaccines for the treatment or prevention of CHIKV infections are not available. As diverse natural phenolic compounds have been shown to possess antiviral activities, we explored the antiviral activity of α-Mangostin, a xanthanoid, against CHIKV infection. Methods The in vitro prophylactic and therapeutic effects of α-Mangostin on CHIKV replication in Vero E6 cells were investigated by administering it under pre, post and cotreatment conditions. The antiviral activity was determined by foci forming unit assay, quantitative RT-PCR and cell-based immune-fluorescence assay. The molecular mechanism of inhibitory action was further proposed using in silico molecular docking studies. Results In vitro studies revealed that 8 µM α-Mangostin completely inhibited CHIKV infectivity under the cotreatment condition. CHIKV replication was also inhibited in virus-infected mice. This is the first in vivo study which clearly showed that α-Mangostin is effective in vivo by significantly reducing virus replication in serum and muscles. Molecular docking indicated that α-Mangostin can efficiently interact with the E2–E1 heterodimeric glycoprotein and the ADP-ribose binding cavity of the nsP3 macrodomain. Conclusions The findings suggest that α-Mangostin can inhibit CHIKV infection and replication through possible interaction with multiple CHIKV target proteins and might act as a prophylactic/therapeutic agent against CHIKV. </jats:sec