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51.
Ravichandran Ramasamy Alexander Shekhtman Ann Marie Schmidt 《International journal of molecular sciences》2022,23(9)
Increasing evidence links the RAGE (receptor for advanced glycation end products)/DIAPH1 (Diaphanous 1) signaling axis to the pathogenesis of diabetic complications. RAGE is a multi-ligand receptor and through these ligand–receptor interactions, extensive maladaptive effects are exerted on cell types and tissues targeted for dysfunction in hyperglycemia observed in both type 1 and type 2 diabetes. Recent evidence indicates that RAGE ligands, acting as damage-associated molecular patterns molecules, or DAMPs, through RAGE may impact interferon signaling pathways, specifically through upregulation of IRF7 (interferon regulatory factor 7), thereby heralding and evoking pro-inflammatory effects on vulnerable tissues. Although successful targeting of RAGE in the clinical milieu has, to date, not been met with success, recent approaches to target RAGE intracellular signaling may hold promise to fill this critical gap. This review focuses on recent examples of highlights and updates to the pathobiology of RAGE and DIAPH1 in diabetic complications. 相似文献
52.
Shayanti Mukherjee Jayarama Reddy Venugopal Rajeswari Ravichandran Seeram Ramakrishna Michael Raghunath 《Advanced functional materials》2011,21(12):2291-2300
Pioneering research suggests various modes of cellular therapeutics and biomaterial strategies for myocardial tissue engineering. Despite several advantages, such as safety and improved function, the dynamic myocardial microenvironment prevents peripherally or locally administered therapeutic cells from homing and integrating of biomaterial constructs with the infarcted heart. The myocardial microenvironment is highly sensitive due to the nanoscale cues that it exerts to control bioactivities, such as cell migration, proliferation, differentiation, and angiogenesis. Nanoscale control of cardiac function has not been extensively analyzed in the field of myocardial tissue engineering. Inspired by microscopic analysis of the ventricular organization in native tissue, a scalable in‐vitro model of nanoscale poly(L ‐lactic acid)‐co ‐poly(? ‐caprolactone)/collagen biocomposite scaffold is fabricated, with nanofibers in the order of 594 ± 56 nm to mimic the native myocardial environment for freshly isolated cardiomyocytes from rabbit heart, and the specifically underlying extracellular matrix architecture: this is done to address the specificity of the underlying matrix in overcoming challenges faced by cellular therapeutics. Guided by nanoscale mechanical cues provided by the underlying random nanofibrous scaffold, the tissue constructs display anisotropic rearrangement of cells, characteristic of the native cardiac tissue. Surprisingly, cell morphology, growth, and expression of an interactive healthy cardiac cell population are exquisitely sensitive to differences in the composition of nanoscale scaffolds. It is shown that suitable cell–material interactions on the nanoscale can stipulate organization on the tissue level and yield novel insights into cell therapeutic science, while providing materials for tissue regeneration. 相似文献
53.
Among many cations that can substitute for calcium in the structure of hydroxyapatite, strontium provokes an increasing interest because of its beneficial effect on bone formation and prevention of bone resorption. Strontium-incorporated calcium phosphates show potential in biomedical application, particularly the doped strontium may help in new bone formation. We have synthesized strontium hydroxyapatite powders at 2 °C by a soft solution freezing method using glycine as the template. The structural and morphological characterizations were carried out on the as obtained powders using Fourier transform infrared spectroscopy, X-ray diffraction analysis and scanning electron microscopy techniques. Strontium was quantitatively incorporated into hydroxyapatite where its substitution for calcium provoked a linear shift of the infrared absorption bands of the hydroxyl and phosphate groups. The strontium substituted bone cement has potential for use in orthopaedic surgeries. The present study shows that the addition of glycine plays an important role in reducing the particle size of strontium hydroxyapatite which could be used for biomedical applications. 相似文献
54.
Kannan Radhakrishnan Sruthi Kalyanasundharam Nandini Ravichandran Subramanian Thiyagarajan 《分离科学与技术》2018,53(1):13-21
Automobile emissions are composed of NOx and unburned hydrocarbon that contribute significantly to major environmental and health issues. In this study, encapsulated Moringa oleifera beads (EMBs) were synthesized using Moringa oleifera pod powder that was cross-linked with calcium alginate and used as a biosorbent for reducing the emission gas concentrations from the single-cylinder diesel engine. The breakthrough curve was attained from single and double stage of fixed bed column by the influence of temperature ranging from (80°C–120°C) ± 5°C with a feed flow rate varying from 8 to 10 kg hr–1 and bed height varying from 15 to 30 cm. Based on the experimental results, the maximum biosorption capacity (qo) was found to be 14.45 and 123.51 mg g–1 for HC and NOx, respectively, and was obtained at 80°C–90°C with double stage of BH–30cm under flow rate of 8 kg hr–1. Further, breakthrough curves were investigated, and the experimental data were fitted using well-established models like Thomas, Yoon–Nelson, and Wang models. In addition, mass transfer models like Weber–Morris and Boyd were investigated to identify the rate-limiting step of the overall biosorption process. 相似文献
55.
S Mahanty SN Mollis M Ravichandran JS Abrams V Kumaraswami K Jayaraman EA Ottesen TB Nutman 《Canadian Metallurgical Quarterly》1996,173(3):769-773
To determine whether counterregulation by interleukin (IL)-10 plays a role in the generation or maintenance of the antigen-specific hyporesponsiveness seen in asymptomatic microfilaremic (MF) patients, parasite antigen (PAg)- and nonparasite antigen (NPAg)-driven IL-10 production by peripheral blood mononuclear cells (PBMC) was studied in 10 MF patients and in ll patients with chronic lymphatic pathology (CP). PBMC from MF patients spontaneously secreted 10-fold more IL-10 than did PBMC from patients with CP. PAg also induced significantly more IL-10 production by PBMC from CP patients. There was a negative correlation between PAg driven IL-10 production by PBMC and PAg-specific T cell proliferation in the MF group. IL-10 secretion by plastic adherent cells from MF persons was higher in response to PAg than NPAg, whereas IL-6 and tumor necrosis factor-alpha secretion were equivalent for PAg and NPAg, suggesting that PAg preferentially induces IL-10 secretion in these cells. Thus, PAg-induced IL-10 likely plays an important role in down-regulating antigen-specific proliferative responses in MF patients. 相似文献
56.
Ravichandran G. Casasent D. 《IEEE transactions on pattern analysis and machine intelligence》1994,16(4):415-420
Advanced correlation filter synthesis algorithms to achieve rotation invariance are described. We use a specified form for the filter as the rotation invariance constraint and derive a general closed-form solution for a multiclass rotation-invariant filter that can recognize a number of different objects. By requiring the filter to minimize the average correlation plane energy, we produce a multiclass rotation invariant (RI) RI-MACE filter, which controls correlation plane sidelobes and improves discrimination against false targets. To improve noise performance, we require the filter to minimize a weighted sum of correlation plane signal and noise energy. Initial test results of all filters are provided 相似文献
57.
58.
The corrosion behaviour of low carbon steel exposed to marine atmospheric, splash and immersion zones has been systematically studied by exposing steel specimens for a period of 12 months at the boat basin corrosion station of Chennai harbour, Chennai, Tamil Nadu, South India. The literature on similar work has been thoroughly reviewed which led to the initiation of this study for the first time at this harbour. The corrosion product (rust) on the specimens at 1, 2, 3 and 12 months was obtained and characterized by Fourier transform infrared spectroscopy (FT‐IR) and X‐ray diffraction (XRD) analysis. Acaganeite was the rust phase identified in the splash zone as revealed by the FT‐IR and XRD analysis. The other dominant phases were lepidocrocite, goethite and ferroxyhite. Small amounts of magnetite were also found to be present. The transformation of phases was observed in this investigation and discussed. A remarkable difference in the FT‐IR and XRD patterns of the corrosion products at the splash and immersion zones were noticed and the corresponding phases formed were reported in this paper. The rate of corrosion in all the three zones was compared. 相似文献
59.
K. Yamakawa D. Ravichandran A. S. Bhalla S. Trolier-McKinstry J. P. Dougherty R. Roy 《Ferroelectrics Letters Section》1996,22(1):41-45
Ferroelectric SrBi2Ta2O9 thin films were prepared from Sr metals, Ta-ethoxide and Bi, 2-ethylhexanoate. The films were prepared from both stoichiometric and 10 mol% Bi rich solutions. The stoichiometric film crystallized at 800°C had a spontaneous polarization value of 5 μC/cm2. The Bi rich film had lower crystallinity, finer grains and a smaller polarization. It was found to be necessary to anneal the films at high temperatures or for long time to achieve ferroelectricity. The non-crystalline states of sol-gel derived films differ from that observed in films deposited by physical vapor deposition. Crack free films were produced with the film thicknesses of 0.4 μm. 相似文献
60.
Kavitha?TupellyEmail author Vladik?Kreinovich Karen?Villaverde 《Reliable Computing》2005,11(4):291-312
In many problems in science and engineering ranging from astrophysics to geosciences to financial analysis, we know that a physical quantity y depends on the physical quantity x, i.e., y = f(x) for some function f(x), and we want to check whether this dependence is monotonic. Specifically, finitely many measurements of xi and y = f(x) have been made, and we want to check whether the results of these measurements are consistent with the monotonicity of f(x). An efficient parallelizable algorithm is known for solving this problem when the values xi are known precisely, while the values yi are known with interval uncertainty. In this paper, we extend this algorithm to a more general (and more realistic) situation when both xi and yi are known with interval uncertainty. 相似文献