1,115 research outputs found
Physiological antioxidant system and oxidative stress in stomach cancer patients with normal renal and hepatic function
Role of free radicals has been proposed in the pathogenesis of many diseases. Gastric cancer is a common disease worldwide, and leading cause of cancer death in India. Severe oxidative stress produces reactive oxygen species (ROS) and induces uncontrolled lipid peroxidation. Albumin, uric acid (UA) and Bilirubin are important physiological antioxidants. We aimed to evaluate and assess the role of oxidative stress (OS) and physiological antioxidant system in stomach cancer patients. Lipid peroxidation measured as plasma Thio Barbituric Acid Reactive substances (TBARS), was found to be elevated significantly (p=0.001) in stomach cancer compared to controls along with a decrease in plasma physiological antioxidant system. The documented results were due to increased lipid peroxidation and involvement of physiological antioxidants in scavenging free radicals but not because of impaired hepatic and renal functions
Design and Development of an Airblast Atomiser for the KAVERI engine and the sectoral combustor tests
This report deals with the design and development
of an airblast atomiser for application in the KAVERI
engine. Five atomisers of the chosen design were
fabricated and tested at ambient conditions to determine
the fuel spray SMD, patternation, cone angle
and atomiser flow number. The atomiser performance
parameters specified were achieved and hot tests
carried out in the 90° combustor sector. The combustor
pressure loss, exit temperature distribution, ignition
and stability limits were evaluate
Recent developments in life sciences research: Role of bioinformatics
Life sciences research and development has opened up new challenges and opportunities for bioinformatics. The contribution of bioinformatics advances made possible the mapping of the entire human genome and genomes of many other organisms in just over a decade. These discoveries, along with current efforts to determine gene and protein functions, have improved our ability to understand the root causes of human, animal and plant diseases and find new cures. Furthermore, many future Bioinformatic innovations will likely be spurred by the data and analysis demands of the life sciences. This review briefly describes the role of bioinformatics in biotechnology, drug discovery, biomarkerdiscovery, biological databases, bioinformatic tools, bioinformatic tasks and its application in life sciences research
Mol-CycleGAN - a generative model for molecular optimization
Designing a molecule with desired properties is one of the biggest challenges
in drug development, as it requires optimization of chemical compound
structures with respect to many complex properties. To augment the compound
design process we introduce Mol-CycleGAN - a CycleGAN-based model that
generates optimized compounds with high structural similarity to the original
ones. Namely, given a molecule our model generates a structurally similar one
with an optimized value of the considered property. We evaluate the performance
of the model on selected optimization objectives related to structural
properties (presence of halogen groups, number of aromatic rings) and to a
physicochemical property (penalized logP). In the task of optimization of
penalized logP of drug-like molecules our model significantly outperforms
previous results
Hummingbird: An Energy-Efficient GPS Receiver for Small Satellites
Global positioning system (GPS) is the most widely adopted localization technique for satellites in low earth orbits (LEOs). To enable many state-of-the-art applications on satellites, the exact position of the satellites is necessary. With the increasing demand for small satellites, the need for a low-power GPS for satellites is also increasing. However, building low-power GPS receivers for small satellites poses significant challenges, mainly due to the high speeds (similar to 7.8 km/s) of satellites and low available energy. While duty cycling the receiver is a possible solution, the high relative Doppler shift among the GPS satellites and the small satellite contributes to an increase in Time to First Fix (TTFF), which negatively impacts energy consumption. Further, if the satellite tumbles, the GPS receiver may not be able to receive signals properly from the GPS satellites, thus leading to an even longer TTFF. In the worst case, the situation may result in no GPS fix due to disorientation of the receiver antenna. In this work, we elucidate the design of a low-cost, low-power GPS receiver for small satellites. We also propose an energy optimization algorithm to improve the TTFF. With the extensive evaluation of our GPS receiver on an operational nanosatellite, we show that up to 96.16% of energy savings can be achieved using our algorithm without significantly compromising (similar to 10 m) the positioning accuracy
Antibacterial studies and phytochemical constituents of South Indian Phyllanthus species
Antibacterial activity and phytochemical tests of the methanol extracts of six Phyllanthus species were evaluated. In agar well diffusion assay the diameter of inhibition zones ranged from 3 - 22 mm. Phyllanthus amarus showed maximum activity of 22 mm. The minimum inhibition concentration (MIC)and minimum bactericidal concentration (MBC) observed for Bacillus stearothermophilus, Staphylococcus aureus, Bacillus subtilis, Micrococcus leuteus, Salmonella typhi, Enterobacter aerogens, Proteus mirabilis, and Proteus vulgaris were 30 - 205 ìg/ml and 40 - 230 ìg/ml, respectively.P. amarus, P. hookeri and P. maderaspatensis showed the lowest MIC (30 ìg/ml) as well as MBC (40 ìg/ml) and thus an effective inhibitor of the tested bacteria. Lignans, triterpenoids and phenols were detected in all the 6 tested plants
Cellular phosphatases facilitate combinatorial processing of receptor-activated signals
<p>Abstract</p> <p>Background</p> <p>Although reciprocal regulation of protein phosphorylation represents a key aspect of signal transduction, a larger perspective on how these various interactions integrate to contribute towards signal processing is presently unclear. For example, a key unanswered question is that of how phosphatase-mediated regulation of phosphorylation at the individual nodes of the signaling network translates into modulation of the net signal output and, thereby, the cellular phenotypic response.</p> <p>Results</p> <p>To address the above question we, in the present study, examined the dynamics of signaling from the B cell antigen receptor (BCR) under conditions where individual cellular phosphatases were selectively depleted by siRNA. Results from such experiments revealed a highly enmeshed structure for the signaling network where each signaling node was linked to multiple phosphatases on the one hand, and each phosphatase to several nodes on the other. This resulted in a configuration where individual signaling intermediates could be influenced by a spectrum of regulatory phosphatases, but with the composition of the spectrum differing from one intermediate to another. Consequently, each node differentially experienced perturbations in phosphatase activity, yielding a unique fingerprint of nodal signals characteristic to that perturbation. This heterogeneity in nodal experiences, to a given perturbation, led to combinatorial manipulation of the corresponding signaling axes for the downstream transcription factors.</p> <p>Conclusion</p> <p>Our cumulative results reveal that it is the tight integration of phosphatases into the signaling network that provides the plasticity by which perturbation-specific information can be transmitted in the form of a multivariate output to the downstream transcription factor network. This output in turn specifies a context-defined response, when translated into the resulting gene expression profile.</p
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