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21.
Monisha Prasad Selvaraj Jayaraman Mohamed Ahmed Eladl Mohamed El-Sherbiny Mosaab Abdella Ebrahim Abdelrahman Vishnu Priya Veeraraghavan Srinivasan Vengadassalapathy Vidhya Rekha Umapathy Shazia Fathima Jaffer Hussain Kalaiselvi Krishnamoorthy Durairaj Sekar Chella Perumal Palanisamy Surapaneni Krishna Mohan Ponnulakshmi Rajagopal 《Molecules (Basel, Switzerland)》2022,27(5)
Natural products in the form of functional foods have become increasingly popular due to their protective effects against life-threatening diseases, low risk of adverse effects, affordability, and accessibility. Plant components such as phytosterol, in particular, have drawn a lot of press recently due to a link between their consumption and a modest incidence of global problems, such as Type 2 Diabetes mellitus (T2DM), cancer, and cardiovascular disease. In the management of diet-related metabolic diseases, such as T2DM and cardiovascular disorders, these plant-based functional foods and nutritional supplements have unquestionably led the market in terms of cost-effectiveness, therapeutic efficacy, and safety. Diabetes mellitus is a metabolic disorder categoriszed by high blood sugar and insulin resistance, which influence major metabolic organs, such as the liver, adipose tissue, and skeletal muscle. These chronic hyperglycemia fallouts result in decreased glucose consumption by body cells, increased fat mobilisation from fat storage cells, and protein depletion in human tissues, keeping the tissues in a state of crisis. In addition, functional foods such as phytosterols improve the body’s healing process from these crises by promoting a proper physiological metabolism and cellular activities. They are plant-derived steroid molecules having structure and function similar to cholesterol, which is found in vegetables, grains, nuts, olive oil, wood pulp, legumes, cereals, and leaves, and are abundant in nature, along with phytosterol derivatives. The most copious phytosterols seen in the human diet are sitosterol, stigmasterol, and campesterol, which can be found in free form, as fatty acid/cinnamic acid esters or as glycosides processed by pancreatic enzymes. Accumulating evidence reveals that phytosterols and diets enriched with them can control glucose and lipid metabolism, as well as insulin resistance. Despite this, few studies on the advantages of sterol control in diabetes care have been published. As a basis, the primary objective of this review is to convey extensive updated information on the possibility of managing diabetes and associated complications with sterol-rich foods in molecular aspects. 相似文献
22.
Krishnamoorthy K Gokhale RS Contractor AQ Kumar A 《Chemical communications (Cambridge, England)》2004,(7):820-821
We report on the design and development of a novel label-free DNA sensor based on conducting poly(3,4-ethylenedioxythiophene) for the direct detection and quantification of target ssDNA. 相似文献
23.
Symmetrically substituted styrenes photochemically gave unstable conformers in low temperature organic glass in a manner consistent with the recently postulated Hula-twist mechanism of photoisomerization. 相似文献
24.
Vivek Ganvir Ashish Lele Rochish Thaokar B.P. Gautham 《ournal of non Newtonian Fluid Mechanics》2009,156(1-2):21-28
Accurate prediction of extrudate (die) swell in polymer melt extrusion is important as this helps in appropriate die design for profile extrusion applications. Extrudate swell prediction has shown significant difficulties due to two key reasons. The first is the appropriate representation of the constitutive behavior of the polymer melt. The second is regarding the simulation of the free surface, which requires special techniques in the traditionally used Eulerian framework. In this paper we propose a method for simulation of extrudate swell using an Arbitrary Lagrangian Eulerian (ALE) technique based finite element formulation. The ALE technique provides advantages of both Lagrangian and Eulerian frameworks by allowing the computational mesh to move in an arbitrary manner, independent of the material motion. In the present method, a fractional-step ALE technique is employed in which the Lagrangian phase of material motion and convection arising out of mesh motion are decoupled. In the first step, the relevant flow and constitutive equations are solved in Lagrangian framework. The simpler representation of polymer constitutive equations in a Lagrangian framework avoids the difficulties associated with convective terms thereby resulting in a robust numerical formulation besides allowing for natural evolution of the free surface with the flow. In the second step, mesh is moved in ALE mode and the associated convection of the variables due to relative motion of the mesh is performed using a Godunov type scheme. While the mesh is fixed in space in the die region, the nodal points of the mesh on the extrudate free surface are allowed to move normal to flow direction with special rules to facilitate the simulation of swell. A differential exponential Phan Thien Tanner (PTT) model is used to represent the constitutive behavior of the melt. Using this method we simulate extrudate swell in planar and axisymmetric extrusion with abrupt contraction ahead of the die exit. This geometry allows the extrudate to have significant memory for shorter die lengths and acts as a good test for swell predictions. We demonstrate that our predictions of extrudate swell match well with reported experimental and numerical simulations. 相似文献
25.
26.
Membrane Disruption and Enhanced Inhibition of Cell‐Wall Biosynthesis: A Synergistic Approach to Tackle Vancomycin‐Resistant Bacteria
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Venkateswarlu Yarlagadda Dr. Sandip Samaddar Dr. Krishnamoorthy Paramanandham Dr. Bibek R. Shome Dr. Jayanta Haldar 《Angewandte Chemie (International ed. in English)》2015,54(46):13644-13649
Resistance to glycopeptide antibiotics, the drugs of choice for life‐threatening bacterial infections, is on the rise. In order to counter the threat of glycopeptide‐resistant bacteria, we report development of a new class of semi‐synthetic glycopeptide antibiotics, which not only target the bacterial membrane but also display enhanced inhibition of cell‐wall biosynthesis through increased binding affinity to their target peptides. The combined effect of these two mechanisms resulted in improved in vitro activity of two to three orders of magnitude over vancomycin and no propensity to trigger drug resistance in bacteria. In murine model of kidney infection, the optimized compound was able to bring bacterial burden down by about 6 logs at 12 mg kg?1 with no observed toxicity. The results furnished in this report emphasize the potential of this class of compounds as future antibiotics for drug‐resistant Gram‐positive infections. 相似文献
27.
John E. Mangette Xuemei ChenRavi Krishnamoorthy A. Samuel VellekoopAdam J. Csakai Fatoumata CamaraWilliam D. Paquette Hong-Jun WangHidenori Takahashi Roman FleckGregory P. Roth 《Tetrahedron letters》2011,52(12):1292-1295
A three-step method was developed to convert N-1 unprotected 3-substituted indoles to 3-substituted 2-acylaminoindoles. Established indole chlorination chemistry was employed to generate stable 2-trifluoroacetylamino indoles, which were subsequently deprotected and selectively acylated. 相似文献
28.
Ganesan K Sehgal PK Mandal AB Sayeed S 《Applied biochemistry and biotechnology》2011,165(3-4):1075-1091
The irreversible destruction of extracellular matrix (ECM) such as cartilage, tendon, and bone that comprise synovial joints is the hallmark of both rheumatoid arthritis and osteoarthritis by over-expression of matrix metalloproteinase (MMP)-collagenases. We report herein the detailed study on the inhibitory effects of Withania somnifera extract (WSE) and Cardiospermum halicacabum extract (CHE) on Clostridium histolyticum collagenase (ChC) activity against the degradation of the ECM component of bovine Achilles tendon type I collagen by hydroxyproline assay method. Interaction of WSE and CHE with ChC exhibited 71% and 88% inhibition, respectively, to the collagenolytic activity of ChC against collagen degradation, and the inhibition was found to be concentration-dependent. The inhibition kinetics of ChC by both the extracts has been deduced from the extent of hydrolysis of N-[3-(2-furyl) acryloyl]-Leu-Gly-Pro-Ala. Both WSE and CHE are provided competitive and mixed type inhibition on ChC activity, respectively. Circular dichroism studies of ChC on treatment with WSE and CHE revealed changes in the secondary structure of collagenase. These results suggest that the WSE and CHE facilitated collagen stabilization through collagenase inhibition. 相似文献
29.
Gautham Santhosh Kumar Chavva Kurumurthy Pillalamarri Sambasiva Rao Banda Veeraswamy Pamulaparthi Shanthan Rao Banda Narsaiah 《Helvetica chimica acta》2011,94(9):1692-1696
CuBr/FeCl3 Catalysis as a novel and efficient method has been developed for the preparation of new aryl propargyl imine ether derivatives via C? H activation of aryl propargyl ethers, followed by reaction with imines generated from aldehydes and amines. 相似文献
30.
D. -T. Lu V. H. Ozguz P. J. Marchand A. V. Krishnamoorthy F. Kiamilev R. Paturi S. H. Lee S. C. Esener 《Optical and Quantum Electronics》1992,24(4):S379-S403
Optoelectronic devices with free-space optical interconnections offer new possibilities in massively parallel processing. The trade-offs involved in system design and device selection for optoelectronic implementations are examined. System design trade-offs are approached from algorithmic and technological standpoints. From the algorithmic standpoint, new architectures based on expander graphs, that have been shown to provide low-contention fault-tolerant communication, are discussed. Optoelectronic systems which implement such random graphs can be folded to reduce the hardware cost or unfolded to increase bandwidth. They can also be partially folded by increasing the grain size or by reducing the randomness of the graph topology to reduce the complexity of the interconnection holograms. An optoelectronic and a VLSI implementation of a multistage interconnection network are compared from a technological standpoint. Physical design parameters, such as the chip size or the number of phase levels of the interconnection holograms, are related to the system design metrics such as bandwidth, volume, area and power. It is shown that the optoelectronic implementations have higher performance and are more cost-effective than VLSI implementations. These results are also used to provide general guidelines for device selection in the design of smart pixels/smart spatial light modulators based optoelectronic systems. 相似文献